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MG Midget and Sprite Technical - Heater tap refurbishment

Good morning :)

Still looking at the small details that annoyed me... When my heater tap was fully closed, it always leaked slightly from the top, so I decided to remove it for inspection :)

Less to save money than to make it more reliable, do you know if it can be refurbished ?
I read few things in the archives, but it was not really clear to me, especially there is a lot of different models of tap...

Thanks !


CH Hamon

A good clean up and a new 'O' ring and it'll be good
William Revit

A picture of the one my car came with when I also took it to pieces.
Quite different to yours Cedric. Maybe the factory used whatever was to hand when the cars were being built?
To stop any potential leaks I leave it open and keep the flap on the heater closed until the heater is needed.


Jeremy MkIII

Thanks Willy ! I would like to avoid to buy a new one, and being in the same situation in few weeks...

What I wonder, is how to put back the top/last washer inside the groove, as the external diameter of the washer is bigger than the internal diameter of the tap... Should I just force it into position ? It gets slightly twisted when I removed it...
Or maybe it will work better with a different washer/stopper, for example the one that you can compress before inserting ? Forgot the name.... EDIT: circlip !



CH Hamon

Jeremy, your image looks like it's of the engine drain tap situated at the rear LH side of the block.

Cedrics image is of the heater tap, situated adjacent to the cylinder head and heater box at the top rear of the engine RH side.
Philip Sellen

Are you sure Philip? On my engines the block drain tap is on a BSP thread, not a two stud baseplate like the tap that Jeremy shows. That does look like a heater tap.
GuyW

Philip, it's definitely the heater tap as I remember taking it off and putting it back on. The engine doesn't appear to have a drain tap.
The photo shows it in situ. It's a pity it still isn't as pristine :(


Jeremy MkIII

Jeremy
I've seen those before, 1/4 turn on/off,as opposed to Cedric's wind out like a tap version-
They rely on the tension of the spring to keep the valve pulled up in the taper to seal, - simple setup but works ok

Cedric
All that washer is there for is to stop you winding the valve right out, A circlip would be fine-
I'd imagine the original washer was a domed shape and they sat it in there and flattened it out, you might be able to get it back in good enough to do the job
When you're screwing it back together you need to put some soap around the hole and around the O ring so that it doesn't catch on that groove and wreck your new ring
William Revit

Jeremy

Your tap looks like it’s from a Morris Minor, or similar.
Dave O'Neill 2

Yes you’re right, I stand corrected.

Never seen a heater tap like that before though. I’m not familiar at all with Morris Minor parts, other than those we share.
Philip Sellen

Jeremy,
your tap isn't a midget tap AFAIK, I don't even think it's from a Moggy or similar (possibly off some sort of steam engine?). It's not original so as you only use it for show and it's not correct for show it'll have to go or you'll be thrown out of (a) club!

If the leak is only potential why not try it turned off, it might not leak, and if it does it'll only probably be very minor (but not Morris).

Lots of the taps leak, the new ones I got from Ashley Hinton now do.



Nigel Atkins

Jeremy,
I think it's one of these - off a Mini.

https://www.ebay.co.uk/itm/Vintage-Classic-Mini-Mk1-Original-Brass-Heater-Control-Valve-Tap-Austin-Morris/362967202019?hash=item548287f8e3:g:-6EAAOSw4ipekF5l

Good old taper cone design - just like Blakes seacocks on boats - nothing wrong with them !
Bit of grease on assembly.

Nigel still needs to sort the meds !

R.
richard b

So, I did buy some seals and one circlip, we will see! At the end, it might cost more than a new one :D

What is a bit tricky, aside the fact that you have to "guess" which O-ring to buy, is the fact that the later ones have the top washer/lid pressed in by force, as the first one just need to be unscrewed....and screwed back.

I am not sure the circlip will do it, as it is not really wide, but I will give it a go and report
(https://www.springmasters.com/product-category/circlips-retaining-rings/internal-circlip-din-472-metric/ - I took the 14/15.1mm)
If circlip doesn't work, hopefully i can use Willy "be strong and push it back" technique :) Thanks for the soap tip too ;)
CH Hamon

Yes Willy, you're right, it is a quarter turn between on and off.

Could be from a Minor Dave, as a bit of image googling shows it's part number 12A479 from a Mini (or Minor or 'Spriget' see http://www.minimania.com/part/12A479/Valve-Heater-Brass-Van-Not-Cable-Actuated-Mini-Spriget-Minor).
Attached image is from Sportsandclassics.com

My wife bought the car in 1977 and this was on it then (I'm not aware it's been changed whilst in our ownership) so it either left the factory with it or the original failed and was replaced by whatever the garage had in stock in its first five or six years of existence.

Nigel, it's not leaking atm and I'm very happy to leave it that way. The photo was taken in 2007 during its restoration with the bonnet yet to be fitted, hence the sad face and the comment about it being no longer as pristine as it was then, now it has a few more thousand miles under its wheels.
Enjoyed your Minor pun :)

Cedric, sorry for the thread drift...



Jeremy MkIII

No problem Jeremy, not very a drift ;)

I wonder if yours is more complicated to manufacture/machining, because it looks like it has less part and the design is more robust !
On mine, I think the ring has a lot of stress, they are turned, compressed, and the top one is kind of expose to dirt... and less "maintainable" than the previous version... Cost reduction ? :)
CH Hamon

Richard,

well spotted, that's the same one, expensive isn't it? I didn't realise it required greasing on reassembly but it seems to be working ok after thirteen years.

Cheers Cedric at least the drift is on the same topic! The design was probably standardised with as you say, the easiest to manufacture and cheapest winning out.
Hope your repairs result in no leaks.
Jeremy MkIII

Early Mini, fair enough, I'm too young to know about such cars. I didn't think the hole in the middle of the base for the water looked the usual size,perhaps I was visualizing the thread aperture on the usual Spridget tap base.

Jeremy,
if it doesn't leak then turn it off, or it'll boil your had or your feet (or should) - but it can stay as it's original to your car, but you will of course be deducted more points.
Nigel Atkins

I keep the heater flap closed during hot weather Nigel so there's no warmth from the heater inside the car.
No heat soak either with the heater matrix being situated on the engine side of the bulkhead and the battery acting as an extra insulating barrier.
I'll take the points deduction but appeal the decision!
Jeremy MkIII

So you have the 'H' knob pulled out providing somewhere to hang a handbag from as the choke isn't used so much in summer.

Or do you have it wired in reverse, like some here thought it should be because they don't read any good books, so that the flap is shut with the 'H' knob pushed fully home.

If you don't get any heat through with the flap shut it proves my point that the flap wants to be fully open for maximum heat into cabin even in winter.

Whatever points you regain from the appeal will be lost against your other many infringements, and against a 1971 model, really, you've a cheek entering, there's no class for modified here.

:)
Nigel Atkins

Agreed, absolutely shocking cheek.

Whilst having the heater flap open will increase airflow, the most significant 'modification' was renewing the foam seal around the matrix.

The original one was perished and air was taking the easier route by blowing through the resultant gaps rather than through the matrix.
With the new foam seal installed, air was forced through the matrix (as intended) and the heat went from pathetic to furnace, especially with the fan on.

Photos explain better than words.(Apologies for the blurry first one).

It's a curry hook Nigel.






Jeremy MkIII

As the self-isolation extended, that is my new job :) On mine, it was just gone into small pieces here and there... I am also missing the two rubbers on the pipe connection, and the steel plates vibration already started to make a hole on the connections...which means it would have (already did ?) a leak one day/soon !

Did you buy the new foam from a classic car specialist, or did you just shop around ? Do you all keep the mesh, buy a new one, or create a new one ? :)
CH Hamon

Curry hook, brilliant idea, not very robust though so obviously you eat a lot of the meal before going home, proper lime pickle to suck your cheeks in, none of this mustard seeds stuff.

Cedric,
either the Midget or the one I done before I just used a bit of spare pipe insulation cut in half, piece either side of matrix and have a foot furnace.
Nigel Atkins

Cedric, I bought one from Moss, probably when at the NEC Classic Car Show when they did VAT or postage free offers. It only costs £2.10, fits perfectly and has made a remarkable difference.
The old matrix was in serviceable condition (i.e. not leaking) so was cleaned inside and out and reused.

Nigel, no the meal is consumed in its entirety at home as I have a custom made helium filled bag which reduces the strain on the heater control switch and has the added advantage of offering additional insulation so the curry stays piping hot.
Jeremy MkIII

Thanks for your feedback and ideas :)

I still have to try my matrix, as the pipe connection is marked: I guess with the vibration and the absence of the rubber, the heater frame "hammered" the pipe connection. I need to find out how deep...

Regarding the foam, I wonder if it is not better to put something else than the foam, as Nigel said: not really for the cost, but after seeing how perished was mine, i wonder if it is not a damp trap... Just wondering/thinking :)

(I am making thread drift to my own thread :p Should remove "tap" from the title :) )



CH Hamon

If it's leaking you could try resoldering the joint Cedric?
Yes by all means try something other than the foam from the usual suppliers but the recommended one fits well, ensures the air goes through the matrix and presumably helps isolate the matrix a little from vibration inside the casing?
Anything which seals the gap between the matrix and the casing should improve the heater's performance.
Jeremy MkIII

All as Jeremy has put.

You could pressure test the matrix before and after cleaning, and after soldering if you do that.

I don't know if there would be much vibration, movement and pressure on the matrix pipes IF the external hoses and pipe are fitted and held correctly - but others might know differently.

I wonder if a heavy battery knocking and slamming against the back of the heaterbox case would have any effect on the matrix pipes. ;)

The rubber grommets that are now used hold the matrix pipes quite tightly to the heater box case panel. Again I might be wrong (has been known) but I think the idea of closing down the gap of inlet/outlet holes in the heaterbox case is at least partly to keep the hot air in the box and possibly to prevent engine bay fumes entering the heaterbox and thus the cabin.

I think I might have put a couple of thin rings of pipe insulation between the matrix and inside of heaterbox once as further insulation but I might just have thought about it, can't remember now.
Nigel Atkins

Jeremy,
proper curry is excellent cold too (room temperature cold not fridge cold). :)

Nigel Atkins

Is there a simple but effective DIY pressure test? I'd like to test both my original heater matrix and radiator at some point.
Bill Bretherton

Bungs, seals, plugs, stops, rags and bicycle pump or mains water pressure?

For matrix there's the John Twist suck test, thumb blocking one matrix pipe suck on the other pipe to get a vacuum, thumb off to hear vacuum release and air rush in. - See 3:20-3:30 on here - https://www.youtube.com/watch?v=2gCN3hbtVgQ

Nigel Atkins

"I wonder if a heavy battery knocking and slamming against the back of the heaterbox case would have any effect on the matrix pipes. ;)"
>No idea what make you think this... :P

"possibly to prevent engine bay fumes entering the heaterbox and thus the cabin"
>That's actually a good point too...

Jeremy,
Yes, I think I will try to solder (or give it to solder) it: I hope everything else is alright !
I see your point for the foam, and it is why I might do the same at the end :p

Bill,
I think it depends how much precision you want, and at which pressure you want to test it. And if you want to do it while in the car, or on the shelve.
I would think that you can make a home made inlet using a foot pump, and an outlet measuring the pressure with a "cylinder compression test" valve, or any other valve. Then you see if any drop of pressure... But it would be really "home made", I guess your question is to have something more reliable/precise/build for the purpose ? :p
I was wondering the same for mine, and I think at the end I will just plug it back, without the box, start the engine and check for leaks :p
CH Hamon

While making my coffee, i realized how stupid I am: just make an home made coupling in any inlet of the system with a manual foot pump (from an old bicycle tire ?), and use the manual foot pump valve to monitor the pressure... One inlet is enought ! Then just monitor if the pressure decrease, or if you can feel any air getting out of the system (is it the ear the most sensitive part for this ?)
I should switch to tea to be smarter...
CH Hamon

Cedric, the innertube idea is a good one - that's what I'll do. Nothing wrong with coffee - I have one mid-morning every day. Preferred brand is Carte Noire (for filter) which you'll know but they've stopped importing it. Next tine we go to France......
Bill Bretherton

Cedric
If you're going to make up a pressure tester, best to do it while you have it apart
If you pressurise it with the matrix in a bath of water you will soon see if there are any bubbles of air coming out------------
William Revit

Bill,
if you're using a foot pump why don't you just use one of the adapters you get with them rather than hunting round for old inner tubes - why keep old sacrificial inner tubes anyway - too much space leads to hoarding, your neighbour will be ringing the council.

A handpump is more control able as with the footpump you have partial body weight being applied and leg muscle are generally much stronger than arm muscles.

On the other side the footpump generally have a gauge on them even if many are very inaccurate you can see if the needle starts to go down (well if the gauge is large enough for your sight, mine never are).
Nigel Atkins

Cedric,
another point about the foam is that, as you probably know, the air pockets in the foam help greatly with the insulation so if the foam has shrunk it's lost most of its air pockets as well as not filling the gap between matrix and heaterbox casing.
Nigel Atkins

I always had a slight weep from my brass heater tap - similar to Nigel's. Tightening and tweaking never made any difference, but it was never a full blown leak, so I left it alone.

When I took the head off for skimming recently, I removed the tap and the plinth. The tap appears to be in perfect working order, however, the internal thread in the plinth was dreadfully corroded and almost non-existent, no wonder it leaked.

It seems as though the plinth is a relatively soft alloy - mazak possibly?

Fortunately finding a replacement was easy, so I hope it will be weep-free when it's all back together - and completely water-tight when I've found the other weep in the radiator header area!

Colin
C Mee

Nigel, my idea was to cut a piece of the innertube around the valve such that it can be sealed to a matrix pipe. Willy's idea to put it in water also good.
Bill Bretherton

Bill, oh right, I thought you meant the valve of the inner tube - but still you shouldn't have such waste stored at your property, how high are your fences!

Any bungbush would surely do though, taper cut and hollow out a carrot then you can still eat the carrot, no waste or storage waste. Got to go that's the Government ringing for more of my idea to help them out - but they just don't listen. :rolleyes:
Nigel Atkins

Some modern cars ( peugeot/Citroen certainly) use a schraeder type valve fitted as a bleed point on a cooling system pipe. I cut off a length of heater system pipe with this fitting from a breaker's yard car and used it for the top heater pipe on my '71 car.
It makes a convenient way of bleeding off that last bit of trapped air when refilling the cooling system. As it's a standard valve, one could use it the other way as a means of pressuring the system to check for leaks, although I have never tried it for that.
GuyW

One can also remove the brass core from a tyre stem, use solvent or heat or both to remove the rubber from the brass, clean then soft or hard solder the brass into a suitable part such as a plumbing fitting to make a test fitting. I've done it a few times, remember to remove the Schrader valve before cleaning and soldering the brass stem.
David Billington

That is a neater Engineer's solution from David, compared to my scrapyard version!

As an air bleed point it ideally needs to be at or near to the highest point in the system, but a valve stem soldered into the heater pipe where it goes above the carb manifold would be close. One could even add a little hump back bend in the pipe to concentrate collection of air at the bleed point.
GuyW

When using foam insulation around the heater core, a closed cell foam would be my choice. The air bubbles in closed cell foam are sealed, so the foam is firmer but most importantly it won't "soak up water like a sponge"! You don't really want to build a wet sponge holding moisture in contact with metal to initiate rust. The downside is it is rather firmer so may need a bit more trimming to get it to fit and fill gaps neatly.

I think the original foam and replacements sold for fitting around the heater are normal and cheap open cell foam. like a car sponge. Soft so it is quick and easy to fit but not what I would use. OK, there shouldn't be any water there anyway, but I wouldn't risk it. Something like domestic pipe insulation is closed cell and would be better. I think it was Nigel who said that was what he used. You can also cut neat circular slices for fitting around the in and out pipes before fitting the core to the casing.
GuyW

I can't remember if I put pipe insulation on the matrix pipes as on the later 1275 (and 1500) matrix the in and out pipes are close to each other but you might be able to square off the sides of the insulation rings to get both to fit and hold each other in position.

I hope I didn't go overboard with too much technical terminology there, I can never think of the correct words (the very few that I know anyway).

Mains water pressure (unless very low in your area) seems easy to deal with but it could get a bit wet so dealing with air seems a good idea especially if it's not a warm sunny day (but farting about again with rarely used items on the car is unappealing to me).

Got to go Boris is on the phone again, we've got to work out how to make it appear that he didn't do a Donald earlier - still look ill, but don't cough, and present with shaggy hair and puppy dog eyes and keep going on about his marvellous NHS treatment until time runs out, will be a start.
Nigel Atkins

Haha Willy, reading your comment, I imagined myself doing it, and the face of my girlfriend when she would spot me doing it :D
But it is definitely a good solution: it is still how a lot of fuel tanks are tested for modern cars !

Thanks Guy for the foam indication. I do agree with you, even more that my car is sleeping outside during the winter: even if no water should be there in the first place, condensation and/or small leaks might get the rust starting again... I care more about keeping the heater system away from rust, than closing all the air gaps... As said before, the inside of the car is either cold, or a furnace :)
CH Hamon

After our discussions about "how to try a heater matrix", I did give it a go between two meetings :)

Just replace the bath by the kitchen sink to consume less water :D My girlfriend's eyes didn't turn red, that's a pass too.

Obviously, it is really "home made" and not accurate (at all): real pressure not known, temperature low and not representative of the cooling system and dilatation of the matrix,... But if it has a "big" hole, you will see it.
I did use a manual foot pump to put pressure in it, it was tight enough to plug it on the rubber hose, and use what I could find to block the outlet, on the rubber hose too (wine stopper, of course :)).

It reached somewhere around 0.75bar on the dial, even though the accuracy is questionable. I think the most important is to build some pressure, hold it, move the matrix around to see if any bubble appears, and then release the pressure. All this passed :) Next check is on the car now :)






CH Hamon

Still, despite this "success", I want to reinforce the area which has been "hammered" on the pipe connector, as I guess the thickness is now really low there...

Sadly, what you can see on the picture are the only things I have available to try a "home made" repair: what do you suggest to use ? Would it be proper and last ? Or should I give it to a professional ?

Thanks :)


CH Hamon

To allow for inaccuracy of foot pump gauge did you pressure up to about 30 psi (2 bar)?

I'd have thought a good wire brush cleaning of the area and perhaps finer cleaning(?) then some soldering to fill gap and act as reinforcing would do, especially if you didn't get a leak. You could leave it rough as it would not be seen or butting up to anything but a gentle brush to smooth the solder when it is hot would give a smoother and better looking finish. This would be good practice for work that will be seen and as good practice to better quality work generally.
Nigel Atkins

What power is your soldering iron, Cedric? The heater core is designed to conduct heat away quickly and you may find that you just cannot get the solder to melt onto it if the iron isn't powerful enough.

But equally, don't get it so hot that the solder runs out of the nearby joints. You could end up with something a lot worse than you start with!
GuyW

Nigel,
I was a bit concerned of adding to much pressure, to not give to much constraint to the assembly... But hard to tell how much is too much!

Guy, Nigel,
So should I just had some filler instead of soldering ? The one on the left on the picture ?
I think the power of the soldering iron is 50W, but the label is not easy to read....legacy from my grandpa !
CH Hamon

If by hammered you mean the rings on the end of the pipes, then forget it - they are there only to help ensure the hoses don't slide off - the seal is made by the clip compressing the hose onto the pipe.
Chris at Octarine Services

Cedric,
the good book will tell you the maximum pressure your system should run to (assuming pressure cap is working and within tolerance), I don't think about double the figure would harm the matrix but would be a good leak test.

Get the magnify glass out as your grandpa's iron might also be 30w or 80w.

Others will know better than I but indoors I'd have thought even 30w would probably do it especially if you warm the matrix up.

As with many jobs cleanliness helps, clean matrix, solder and iron.
Nigel Atkins

Chris,
Sadly, it is more the lack of grommet + perished foamed which made the matrix seats lower in the heater box, and the heater box making its way through the matrix... (circled in red)

Nigel,
I am not really handy with a soldering iron...That's why I was wondering if putting filler would not have the same result ?
Of course, I will try to do a proper job: nothing better for me than training on non-visual areas :D


CH Hamon

Cedric,
you'll be fine, I reckon I could do it so you'll be able to do it. Practice on something else. Just remember to keep things clean and neat. Prepare properly, do not be in a rush, take your time and do the work properly.

Having your tools and item (soldering iron, matrix and solder) clean before you start, during and after. Never put your tools away uncleaned, slackness like that can lead to a poor attitude and quality of work.
Nigel Atkins

I don’t think a soldering iron is going to have enough power to heat up the area so that the solder with flow and wick into the crack.

I repaired a similar crack on the outlet to the overflow tank on the radiator with careful use of a blow torch, solder and some flux paste.



Chris Madge

Does Madame Cedric have a kitchen blow torch for crêmes brulées?

Might give enough heat - just a thought, but probably best investigated when you've got the house to yourself!

Colin
C Mee

You both may be well right but I think if you get the matrix perhaps very warm or hot, instead of warm, and have the iron well preheated and ready then to run a thin bead as a precautionary filler rather than full weight joint, might work. If it doesn't work you'd soon know and you could heat it and suck it out or brush it out, or just leave it, or leave it and run fresh with a blow torch.

- OR -
What about using some Liquid Metal Filler instead(?).
Nigel Atkins

Cedric,

I don't think a 50W iron is anywhere near big enough for soldering that heater core as the brass will be too good a heat conductor and draw the heat away before the area gets hot enough to melt the solder. I used a 50W iron to replace the electrolytic capacitors on a couple of Dell motherboards and that worked OK set at max temp and those PCBs would have had thermal reliefs to lower the heat conduction away from the joint https://en.wikipedia.org/wiki/Thermal_relief . As Colin mentioned a kitchen butane torch may do it and they're cheap and readily available.
David Billington

A soldering iron won't work - you'll end up with splodges of solder and what is called a "dry joint". You need a torch but you also need practice at using it on some scrap metal, a tin can maybe, NOT aluminium. Cleanliness and flux are your friends and just enough heat so the solder flows. Too much and it'll all melt off.
Bill Bretherton

Fair enough I thought you might be able to get the matrix warm enough to just run solder in what is probably just surface cracking as the matrix passed a pressure test.

Whereas even the crêmes brulées torch might be a bit overkill and you'd want to use plumbers solder and flux and probably more practice required with these.

What about the liquid metal, just squeeze it out of a tube and refine as required.
Nigel Atkins

Metal araldite or JB Weld might do it.
Bill Bretherton

Thanks for the advises !

Using some body filler (Dinitrol Alu 6030) would not work ? Would it be a "cold joint" too ?

Sadly, Mademoiselle (!) Cédric doesn't do crèmes brûlées, and her birthday just passed... Might have to make a gift to myself then :)

When you mean "solder/soldering", do you mean to add tin when it is hot...?

Not as simple as I thought, for a change :p
CH Hamon

Cedric
"Soldering" means the application of a lead/ tin compound (or lead free now I suppose) following heating with a blowlamp/ torch (lower temperature than brazing, much lower than welding). You'd use "plumbers" solder and flux as used on copper plumbing in buildings. I wouldn't use filler, it's not waterproof and is just the wrong material.

Metal araldite or JB weld would be my choice if I couldn't solder it.
Bill Bretherton

Lead free solder is only required for potable water systems and food contact applications, lead bearing solder is still perfectly legal for engineering applications. I wouldn't use any sort of adhesive, I'd solder it but then I would say that as I have all the kit and selection of solders and fluxes to do it.
David Billington

David
I once replaced the distributor hall sensor in a Volvo 740. The module supplied had integrated steel rivets which were supposed to be peened over against the soft alloy distributor plate but it was virtually impossible and risky so I bonded it in with metal araldite. It held for years so I trust it. I've just bonded a plastic float to the Frogeye fuel sender arm with JB weld, which is supposed to be fuel retardant. We shall see.

But, agreed, solder is best in this case.
Bill Bretherton

The way I would solder that is with an old-fashioned copper tipped soldering iron that you heat with a gas flame. Mine has a good chunk of copper which holds suffient heat and very quickly transfers to the area to be soldered raising the immediate area high enough for the solder to flow. Touching the solder tip briefly onto the solder keeps it liquid just long enough to flow into the seam/split without the heat spreading into to adjacent areas of the radiator where it could melt out other joints.
GuyW

Ok, so obviously, I am still as bad at welding as I was at secondary school...

I did buy the Miss a crème brulee burner (shh :)), and I struggle to get the tin going where I want it to be... It just melt and slide down wherever it wants to go...

I do take care to have the flame not too strong or too long on the matrix, but I am also concern about making a cold soldering... "Funny" thing is that I can't tell if the matrix is hot enough or not, and while trying to heat it, I even "succeeded" to slide slightly one connector... There are soldered like this in the first place ?

My "tin" says "Rosin core solder" on the box, "lead free" and "best for electrical". Is it not fit for purpose ? I thought tin is tin... Already having poor welding knowledge, not making it in my mother tongue is adding some challenges to it :) Hopefully you are here :P






CH Hamon

I also found Jean-Luc :) If you look from 5:40, he is showing how to solder... I heat much less than him, still the tin melt, but the matrix is really hot and the connector might move... And my tin is liquid and fall down...

Do you do like him too ? Do I miss something ?

https://www.youtube.com/watch?v=-YfTqZvDNYw
CH Hamon

ETA: you posted whilst I was typing - I assumed by the photo you had finished and the pipes had held - if so pressure test, if not do not get water in matrix as soldering does not like water.

Blimey, no wonder you struggled with that flame-thrower!

As has already been proven in this thread my knowledge and experience in this subject, like so many others I respond to on here, is tenuous but I think you'll be alright. You don't want plumbers solder on electrical but as this isn't a food or drinking water item (see other posts) it doesn't matter in that respect at least.

Just pressure test again, but allow for the inaccuracy of the foot pump gauge, to 30psi (2bar if you must) to check for leaks.

If the pipes remained in their positions and fairly solid you probably got away with it.

For future you can wrap the areas you don't want to melt in cold wet cloth to keep them cooler and not start a fire, difficult with the pipes being so close though.

As long as you had everything clean and flux to solder you should be solid, the pipes *look* straight in the photo (to my wonky eyes).
Nigel Atkins

I couldn't understand a word Jean-Luc was saying!

But he is a messy devil, he dropped the cleaned short bit of pipe on the floor but picked it straight back up and put it in the fitting without cleaning again. Slap-dash with the flux and solder, I had to stop watching. Don't follow such sloppy workers - it explains your wire connection!

He also very vintage with his tools and cleaning materials.

Up to the point I stopped watching he was soldering into fully supported pipe and tee-piece fitting without other pre-solder joints, you had an unsupported pre-soldered joint.

If your solder is running off it be any combination of too hot on solder and/or matrix or applying too much solder or not close enough to joint. - or just as likely I have missed something or got something wrong, see what others think.

Nigel Atkins

Cedric,

Rosin core solder is fine for electronic work but for your job I would be using a flux I could paint onto the joint like used for plumbing, clean the joint well before applying to get rid of any paint or corrosion. The solder balling and running away sounds like the usual beginner fault of trying to heat the solder rather than the joint, you need to heat the joint until it starts to melt the original solder to indicate the right heat and then apply the solder to that and it should join with it. Controlling the heat by wafting the flame over the joint should enable you to control the flow. I've not used modern lead free plumbing solder but would expect it to be fairly fluid as it's intended to flow into plumbing fittings around the tube by capillary action. For your job I would chose a solder with a wider pasty range, the difference between solidus and liquidus temp, to allow a good working range and a less fluid solder to allow a fillet to be built up, something like a 40 Sn 60 Pb maybe. See tin lead phase diagram https://www.researchgate.net/figure/The-lead-tin-phase-diagram-Adapted-from-Binary-Alloy-Phase-Diagrams-2nd-edition_fig68_334465619 .
David Billington

I like the creme brulee torch Cedric. I covet that like mad!
In this case I completely agree with Guy about the old style copperhead tool. (Confusingly they were called "bolts" when I was young).
I made my own but I can't show it to you - it's about 400 miles away. But I successfully repaired a split seam in the header tank of a Scania generator engine with it using ordinary plumbers bar and flux paste. I think the paste was called "Fluxite", spookily enough.
Your beautiful torch would be the perfect weapon to heat up a copperhead, but if you use a paste or liquid flux it's essential to clean off any residue afterwards as it can cause corrosion.
Greybeard

Cedric
As already said, you need a flux paste as used in plumbing which you brush onto the cleaned joint. Apply heat gently to the joint, moving the torch around constantly. As David said you want the heat of the metal to melt the solder, not the torch. You are getting the solder too hot by pointing the torch at it. It's a balancing act between getting a nice flow of solder around the joint and making a mess, which is very easy to do, I still do sometimes! Practice, practice, practice!
Bill Bretherton

I think the tool and material used by Cedric are getting mixed up with Jean-Luc's plumbing efforts.

I'm certainly mixed up.

Is it a mix of (bigger) flame torch and thin solder strip with flux already in, has the repaired joint held, is the previously good pipe now wonky. I'm never normally this confused. :)
Nigel Atkins

Nigel
You don't want solder with flux built in - that's for electronics work. You want plumbers type solder paste and separate solder. You might need to play the torch on the joint after soldering it to get more flow - bit of an art!
Bill Bretherton

That Jean-Luc video that you found, Cedric is a poor demonstration of how to solder pipe joints in whatever language you choose! Any apprentice presenting work of that quality at a UK college would be sent away to strip it all down and start again!
GuyW

Bill,
I know what you mean but Cedric's photo only shows a reel (reel, that's the word I couldn't think of before), reel of electronics solder. Unless Cedric got some plumber's solder and flux. He'd need a barrel of flux if he used it like Jean-Luc. I didn't look any further than 6 minutes on the video, it was a real video nasty. Is that the standard they generally work to in France or is Jean-Luc just a sloppy DIYer.

So, if I put the precleaned matrix in the oven at say 90c and prepared the 50w soldering iron then quickly took the matrix from the oven in a heated room, wrapped it to preserve heat as long as possibly (with one of the wife's best towels probably) would it not work using the electronic solder, going into existing solder?

I might find something more insulating than one of the wife's towels but it'll do if I can't - keep it to ourselves!

Nigel Atkins

Nigel
Plumber's solder is in a reel although thicker. Also in bar form, which I'd probably use for the radiator as you can melt more of it quicker. Electronic solder has the wrong flux.

But why go to all the trouble you're suggesting? It might work but it's unlikely to get a smooth flow of solder around the pipe that needs to integrate with any existing solder and produce a good joint. A cheap blowlamp is far better or maybe the copper iron Guy suggested. The right tool for the right job surely?
Bill Bretherton

Bill,
I'm with you, always best to have right tools and materials for the job. I was just trying to join the ingenuity of using what you have to hand 'in the shed' type of thing.

Better to have prevented the matrix pipe crack in the first place but we won't go into that.

As the matrix passed the pressure test I thought a ring of added solder might be enough and although the reel of solder shown in the photo appears to be electric type would it really matter that much if it mixed in with existing or sat more as a surface covering (and into crack of course). I don't know, is it going to rot out the matrix before the rest of the car.

I wouldn't fancy using that reel of electric solder with that blow torch though, is that what happened, that'd take a lot of bravery quickness and dexterity I'd have thought. As normal I'm a little confused but more so with my very poor English trying to understand Cedric's excellent but second language English.
Nigel Atkins

Don't put the whole thing in the oven! Bad idea!!

That video is an amateur - a professional wouldn't be doing it in a living room on a rickety table using those materials.

Plumbing solder for copper pipework comes in solid wire about 2mm diameter - no flux inside. You can get plumbers solder in bars for making wiped joints to lead piping - same is used for lead loading car bodies, it has a wide melting point that allows it the be moulded and pushed around using a tallow coated paddle.

All that needs to be done is to heat the offending pipe and pull it out as the solder round the base melts.

Clean it all up back to bright copper, paying attention to the inside of the hole in the tank. If there is a crack in the pipe then either cut the pipe shorter to eliminate the crack or cut a ring of copper pipe to cover the crack .

Coat the inside of the tank hole, the pipe and if used the sleeve with flux, fit it in the tank hole and heat the open end of the pipe until solder applied to the joint(s) melts and flows - no need to dab the solder round a joint as shown in the vid - just hold the solder at 90 degrees and push it in, it will flow by capillary action all round inside.

For non soldering fix, I would clean it up, cut a section of 15mm copper pipe and split it, fold it round the pipe having applied epoxy glue to the surfaces - applying gentle heat to the pipe will cause the glue to run clear and harden fast.

I have fixed an oil pressure fitting using this method which held for years at over 50 psi!
Chris at Octarine Services

No oven heating, fair enough, I'll never get the hang of this shed repair stuff, I was just trying to get into this spirit of make-do mending.

But Chris I'd suggest you've not had a plumber in to do work for about the last 30+ years if you think it isn't possible for Jean-Luc to be professional and demonstrating that way - but I was joking I think Jean-Luc is very amateur but so are many paid professionals I can assure of that many times over with mechanics let alone plumbers.

Why wouldn't using liquid metal (filler?) to fill and cover the cranking be the quickest and easiest solution, if you don't have plumber's solder and flux and practiced at using them?

Nigel Atkins


Why wouldn't using liquid metal (filler?) to fill and cover

Because it might crack with vibration.
Chris at Octarine Services

I am always reminded that the difference between an amateur and a professional is simply that one gets paid and the other doesn't. It doesn't necessarily indicate quality or skill Except that the professional is likely to have done the job far more often and may have had more practice and/ or training.

Of course some professionals are cowboys and some amateurs are fanatically skilful.
GuyW

Fair enough Chris, I thought there were different sorts of this liquid metal filler stuff or different fillers that might do the job, but don't know as I'd just either plumber solder it if I had the materials or get a good s/h matrix or buy new but I know Cedric wants the joys of repairing.

Guy, I totally 100% agree, adding, most amateurs and professionals being somewhere between the cowboy and fantastically skilled and some amateurs do take payments.
Nigel Atkins

Hi all,

Thanks for your advises, makes a lot of sense! I can see you didn't like Jean-Luc, and I start to think that French are not gifted for "welding" after my second attempt, maybe that's why we didn't bother giving it more words and vocabulary...

So I did go for "tin with lead", loaded between 50 and 70% of lead according to the data sheet. It did behave really different, more "pasty", easier to apply. Almost like concrete, so 40% as advised would have been better I guess, but I couldn't find it "easily".

Still, as you can see, it is far from looking good... Still need a (lot of) practice! Happy I experimented on non-visible parts!

What you think ? Hard to tell from pictures I guess... I will leak-test it when I will have some time.

Should I apply some product on it, to "protect it ? Primer ? Ether ?






CH Hamon

Buying a new matrix would have been definitely more cost and time effective... You can see on this picture an attempt to make the blowtorch purchase more profitable !

Slightly better than my soldering skills...Need to practice too :) The BBS is full of ideas, thanks ;)


CH Hamon

Bravo Cedric.

There are some things that come down to just plain skill - welding and soldering are just a couple - and I haven't mastered either but it looks as though you're well on the way!

I'm sure Mademoiselle Cedric will approve of your new acquisition, just make sure it doesn't disappear into the kitchen for good.

You, though, have clearly mastered the skills required for preparing a crème brulee!

Bon appetit.
C Mee

It may well be the lens or camera angle but one pipe looks like it has a slight lean to it so check the matrix pipes go through the holes in the heaterbox with the grommets fitted on. Otherwise the flares on the pipes may push the grommets off and make the grommets very fiddly to fit or refit. (I hope at that makes sense.)

Other than a bit of cleaning up to I wouldn't bother with the pipes as they are either inside the heater box or covered by the hose, and they don't need anything on them anyway. Keep the coolant refreshed with thorough changes at suitable intervals will keep the inside of pipes and matrix protected and hopefully clean.

Nigel Atkins

Well done Cedric. Take care to wash off any residue from the flux though. Soapy hot water and a stiff brush will be fine.
Greybeard

"I'm sure Mademoiselle Cedric will approve of your new acquisition, just make sure it doesn't disappear into the kitchen for good."
=>Reminds me of my Dad, always running after his screwdrivers: my Mum found them handy to refurbish the house here and there :P

"It may well be the lens or camera angle but one pipe looks like it has a slight lean to it so check the matrix pipes go through the holes in the heaterbox with the grommets fitted on"
=>It is a mix of both the picture and the reality :) I will try when the box paint will be dry ;)

"Take care to wash off any residue from the flux though. Soapy hot water and a stiff brush will be fine."
=> Done ! Looks less "burnt" now :)

So I did try it to 20PSI today as Nigel proposed to increase the pressure (I stopped there because I was concerned of my home-made stoppers to fly away...Please think of it too if you do the same!), and despite the "piggy" look of my weldings, it does hold pressure without bubbles ! For the moment at least... Next trial will be on the car !
CH Hamon

Très bon Cedric! Maybe too much solder but we all do that. The shinier the solder, the better the joint. I wouldn't paint it, it won't rust.

Our kitchen blowlamp broke so now, when we have Crème brûlée, I use my garage blowlamp.
Bill Bretherton

Well done Cedric. Its very satisfying to learn a new skill and fix rather than just get your credit card out and replace.
Chris Madge

I've been Heath Robinsoning again!

My radiator has a nasty habit of collecting a small amount of water on the lip round the header tank just beneath the top hose connection. With the radiator out, and having followed this thread, I thought it was time to test it.

Blanking the top and bottom hose connections was easy - 'holy' vinyl gloves doubled over capped off with thick polythene to stop inflation and all held tight with a jubilee clip.

As none of the plumbing fittings I had matched the temperature gauge threat, I did a bit of head scratching and then started scavenging.
I cut about 6" off a spare length of 1" bore pond pipe as that fits over the temperature gauge spigot perfectly. Clamped with another jubilee clip.

My plumbing box turned up a 22mm straight fitting, a 22/15 reducer and a short length of 15mm copper pipe. Solder together - simple - NOT! What is it about modern copper? The lead-free solder just wouldn't take, it just bounced off. I had the same thing happen recently when I had to replace a short length of pipe in the central heating. In the end, an old piece of 1/2" copper pipe took the solder immediately and saved the day that time. My attempt at brazing with a blow lamp failed, so I resorted to Araldite! The copper pipe had been cut with a wheel cutter and the turned in end provided a thread for a screw in male compressed air tail. A bit of Araldite made sure that the joint was sealed.

Next I plugged the air line onto the set-up with the absolute minimum of pressure. The rather worrying hissing noise stopped when I closed the drain tap!
I didn't want to take the electric fan off, so I dribbled soapy water from a jug. Lo and behold, bubbles - but only from the top hose/pond pipe connection, so perhaps that's what's been weeping all along although I've never caught it at it - at least I won't have to try a soldered repair to the header tank joint, which was what I was expecting.

I cranked the pressure up to 25lb/sq in with no problems, although I think I need a new radiator cap as there was some leakage round it.

If I't had a spare car or bike inner tube I'd have used that, incorporating the valve, but all my old tubes went in a recent clear out.

This time I've included a proper Heath Robinson for those who haven't come across him before.

Colin






C Mee

>> I think I need a new radiator cap as there was some leakage round it.<<
Maybe not Colin. Radiator caps are designed to crack open and relieve excess pressure. They often have the cracking pressure stamped/engraved on them. 25psi is a lot for a cap. I had to renew the caps on the LifeBoat engines recently as someone had fitted 7psi caps and CATs spec is 13psi and I was losing coolant into the catch bottles.
Could be your cap is fine and just doing its thing...
Greybeard

Thanks Greybeard.

After posting I went to look check to see if the pressure was marked on the cap - it wasn't, however, I'm wondering now whether the cap was only on the first click and not fully closed. I'll check it all again tomorrow.

I ended up holding the pressure in the radiator by closing off the over-flow pipe - it plays a lovely musical note when you release the pressure and just let it blow through! It gives a new slant on tuning the car!
C Mee

Reading this thread with interest and then noticed the picture of Jeremy's engine bay and for some reason realised the hoses to the heater matrix were the opposite way around to the ones on my car. On mine the hose from the tap goes to the lower one on the heater matrix. Does anyone know if it makes any difference?
Dave Warren

Dave
Yours is correct , the flow comes out of the head (tap) into the bottom of the matrix, fills the matrix and then returns to the w/pump

If plumbed the other way it can create an air block in the matrix causing the heater to not create much heat at all----you can usually notice a trickling sound in the heater when they're like that
William Revit

Talking of rad caps, what IS the correct pressure rating for the vertical flow rad please? Mine currently has a 7lb but seems to overheat and release water too quickly when stationary (there's no fan) - would a 15lb be better? And is there a reliable supplier of the deep cap required?


David Smith

Dave

Its 7lb. How much is lost? My fanless modsport did it a little when the weather was hot but nothing significant and certainly the level could still be seen in the header. I did change from a 2 core to a 3 core rad as on hot days at full chat on circuits like the old Snetterton/Oulton Park it did get quite hot
Bob Beaumont

David,
if you've got a selection of 7lb caps you could pressure test them for variances, your existing cap might be the weaker of the group.

Would 15lb create problems to the three flute rad top tank(?).
Nigel Atkins

Yep, I'd be getting the cap tested to make sure it holds 7 lb pressure
Why not run a fan-----------
If you're fanging around the track getting everything hot and then going back to the pits with no airflow then turning it off ,you'd have to expect a bit of after turn off heat soak/expansion
William Revit

There's a formula, or a chart, that tells you how much boiling point is raised at different pressures. You could use this to determine which cap you need, depending on what temperature you are wanting to operate at. Only, sorry I cannot find it just now!
GuyW

I think Nigel is right:
"Would 15lb create problems to the three flute rad top tank(?)."

I think I'm right in saying that's why they redesigned it to 4 flutes, as the earlier radiators top tank could deform under undue pressure.
Philip Sellen

Well you learn something new everyday! (Dave and Willy's comments on the heater pipe connections).
As far as I can remember it's always been connected that way round(well since 1977) so that layout was copied when I restored it.
The heater is volcanic so I must have got away with the airlock problem. Looking carefully at the Moss catalogue shows the correct connection when you know what you're looking for.
I'm still to do the 'Atkins flush' for the cooling system so may take the opportunity then to connect them the right way round.
Better not get an air lock Willy! :)
Jeremy MkIII

I noticed on a photo of my car that the hoses were connected the wrong way, but luckily no one noticed knows about that. I can't remember how long it must have been like that but they were no adverse effects but my heater tap is normally closed.
Nigel Atkins

thanks all; it was as Bob said, lost a bit but could still see the level in the filler neck once it had calmed down. A new cap wont harm, but it sounds normalish so I'll stop worrying. Rolling road tomorrow so will keep a close eye on the (new) gauge.
David Smith

Phillip,
I don't know but as a race car I wondered if it might have unseen reinforcement to the rad top.
Nigel Atkins

Very easy to adapt it to an expansion tank variety which would at least stop you having to keep topping it up.
GuyW

This thread was discussed between 16/04/2020 and 01/07/2020

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