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MG Midget and Sprite Technical - Carb leaking petrol

I am gradually getting through some shake-down tests and fixes on the Frog. One recurring problem is an overflowing front carb. It did this when I first set it up but fitting Vitron tipped needle valves seemed to have cured it. But intermittently it is still happening. They are new carbs, so new floats and lid gasket which otherwise might be the culprit. Any other ideas to check?

It has a standard points SU pump but no in line filter. Would adding one stabilize or reduce the fuel pressure?
GuyW

Have you checked the float level? It might be borderline. Or a bit of dirt in needle valve. Both worth checking. I don't think that a filter will alter the pressure much. But that's just my opinion.
Martin

Thanks Martin. The carbs have the later style floats which are supposed to be pre-set by design, but I am willing to try anything. I think the only way of adjusting on these would be to add a washer under the fixed part of the fuel valve.

And again, it could be dirt but everything from tank to carbs is new plus the fault is intermittent so difficult to trace.
GuyW

Guy...I suffered an overflowing front carb...petrol leaking via the small overflow hole beneath the inlet spout. I have an in-line fuel filter. When dismantling the float bowl I detected a small lump of gertcha which was stopping the needle sealing. No...I don't know how it got there either....maybe on assembly??
soon cured though with a thorough clean out. Good luck. Dave
David Cox

Guy,
an inline filter should sort it.
I know it makes no sense to only effect one carb but I had the same issue with my 1300. Unless your tank (everything?) is new I would chuck one in before looking at the float chamber again.

Best of....
MGmike
M McAndrew

Yes Mike. New tank, all pipes, SS pump and carbs all brand new. It was flooding intermittently when I first started it up and was setting up the carbs for the first time. I swapped various parts but nothing seemed to work until I changed out the steel tipped jets for Vitron tipped ones. That seemed to fix it at the time and I thought it was sorted. But now it's on the road the problem is back, but intermittently again.

I guess it's back to basics and check through and inspect everything closely again.
GuyW

I'm not sure why being new SU makes them less suspect, you'd suspect any other new parts, is the new float floating ok and at all times, any "rough edges" to it or its mechanism, pin bent or pitted/rough or locater lugs.

Also, altho' I might have remembered wrong, aren't these new carbs new from a few years ago and have been in storage until recently (I might have dreamt that bit).

I'd get a good magnifier (or take a hi-res photo to blow up on large screen) and have a good look for dirt where Viton needle sits or hush my mouth as the carbs are new any slight imperfection from manufacturer (not that there will be because it from SU!).

As it's an internment problem and, hush my mouth again, SU fuel pumps can through up intermittent issues have a goo look at that make sure all of its requirements are fully catered for including airways as it could already be a wheezy old thing and restricting it more might give it hesitations and bursts.

Blowing, sucking, vacuuming open ended sections of fuel hoses and pipe to clear any partial and interment obstructions.

Toffee hammer to just keep tapping fuel bowl and mallet to hit fuel pump or heel board, surely these are parts of your SU kit kept in the boot.

It's intermittent surely that provides the fun of frequent investigations and roadside warrior heroics, gives loads of opportunities for repair satisfaction, you lucky, lucky devil.

https://media.tenor.com/images/568c33d05178675ea5c083959f9ab186/tenor.gif
Nigel Atkins

Thank you Nigel. Very helpful.
GuyW

My penniworth.
Usually it's the rear carb that suffers this most, and in my experience it is always the jet, and or it's seating, or dirt getting between the two.

If the front is being subjected intermittently to too much pressure, then so is the rear, and yet it's not leaking. No harm in a filter, but unless there is debris in the system it won't fix it.

As nigel said, magnify if you can the jet and seating. Dirt or irregular surface.

Take the jet assembley from the rear and put it in the front. Has the problem moved to the rear?

Test the seating. Things I've done.
Can you pull a vacuum?
Take off the lid and hold it so that the float closes the jet under gravity alone. Suck and seal the pipe with your tongue. Does it hold a vacuum. You can feel it with your tongue if it does.

Can it take pressure? Hold it upside down. Let just the float weight and gravity do the job. Can you easily blow the jet of it's seating?

Hold the lid upright in a bowl of water, causing the float to close the jet. Long tube on the inlet pipe. Suck and blow as above. What happens?

Put on an hif? 🙃

anamnesis

First carb, of twins, leaking because it is first in line to receive detritus. Fit a filter before the carb bowl. It is not an uncommon problem.
Alan
Alan Anstead

Thanks Anamnesis. I had tred all of those tests when I initially had the problem. Except for the bowl of water version. The difficulty is the apparent randomness of it. Altering one thing at a time should pin point a problem but in this case as the fault is intermittent it may or may not continue to leak after making any single change. So you think its fixed when it isn't and its easy to loose track of which combinations of parts and tests you have tried.

When I fitted the Vitron tipped needles it did seem to stabilise so I thought that was it. But yesterday when I was fitting and installing my new dual function LED indicators I had the ignition switched on for a few minutes without the engine running and the front carb began dripping fuel. I had also noticed that at lower speeds in use I was getting a strong smell of petrol.

Of course the problem now may not be the same as when I was setting it up. Maybe the Vitron needles did fix that problem and this is now just a bit of crud as Alan suggests. It doesn't have a fuel filter and my other car never has had either. They shouldn't effect the pressure but might perhaps smooth out any pulsing from the pump. Plus catch dirt!
GuyW

An obvious basic test which I missed but anam didn't, but you've probably already tried, the swap of float and lids. I'm not for the sucking fumes on the bowl lid though, nasty taste and possibly not good for you, I'd sooner hold the float to keep the valve shut, listen then sudden release, do that a couple of times as a test and hopefully disturb and debris.

If the overflow is very intermittent and not too bad then it might clear/clean/cure itself with just use of the car the movement of the parts, components and car. Being static things dry out, stiffen, corrode and crud up active use reasonable regularly/frequently literally keeps things moving. An occasional full flow of WOT (for those of us with it available) will keep a god level of flow, an Italian tune-up.

I've normally had a filter just before carbs but not always, I've never *noticed* any difference either way. Having a petrol filter can good, and not, as you can see the petrol made it that far but if petrol in it is low at after car standing or you see an air bubble or bubbles you might think it better mot to known.

I think I've seen where some have put not to have a filter with an SU pump but I think that might be debateable. With my Hardi I'm suppose to have a filter before it but I never haver, one day I will pay for this foolhardiness.
Nigel Atkins

I've got a dual vacuum/fuel pressure gauge. Draper. Cost me about 10 quid a few years ago.

If you have similar, can you put a "t" in the fuel line and rig up the gauge.

With the ignition on and the engine not running, vibration elliminated, either the sealing of the jet is marginal, or the pressure is building because the pump isn't stopping, and is overcoming thr seal. BUT, why isn't the REAR leaking, given that at all times it's subject to the same conditions as the front?

When it leaked with the engine not running, did a sharp tap on the bowl or lid stop the leak? If it did, it can onky be a dodgy jet or seat or both I would think.

Definitely frustrating and bloody annoying, again I know from experience. Partly why I fitted an hif. But I put my twins back on to experiment, and since fitting viton jets and new seats, I 'rarely' get the problem. HOWEVER, I still do, very infrequently, but only running, which I put down to vibration.

anamnesis

I was editing my last post based on Guy's last post which as often happens to me was posted whilst I was still typing, then anam posted.

This was/is the part substitute.

I've had the rear overflow but I think that was because of the choke sticking on it or other stuff catching, perhaps dirt/debris/crud, it's not done it since I've finally managed to stop the choke on the rear sticking which I thought I'd stopped at least once if not twice before.

The movement, vibrations of components and parts with the vehicle being driven reasonably regularly/frequently can often help with intermittent problems, or other way provoke them to be less intermittent so possibly easier to find.
Nigel Atkins

The flooding last night with the engine not running was as I sorted my indicators. It was late, so I just switched off and let the fumes dissipate. I've not investigated further. But I realise from petrol smell that it has been doing this on the road as well. I will probably get to take a look at it again this afternoon.
GuyW

When you were on the road were you going far enough and varied enough, rather than taking the handbrake off and rolling down the drive or lane that some think of as a drive.

Roads with the 'chippings' surfaces can be good as you can get a good constant level of vibrations for a sonic clean. Pump your tyres up more, vary your speed, plenty of braking and or gearchanges and steering wheel movement and of course if your car is at that stage a bit of Italian-tune-up.

Even if it doesn't work you've had a good drive, sometimes that helps with motivation and fresh thought too. 😁
Nigel Atkins

Last test drive in it was Friday. About 20 miles (Speedometer not working yet) Varied use from grass-up-the-middle lane to A6, Shap summit and town traffic. Only noticed fuel smell at low speed in latter.
GuyW

And this morning, leaving the ignition turned on for 25 mins and it's not visibly leaking !

But the sky is.
GuyW

Precipitating persistently here too.🤣
anamnesis

Surely it's just a bit of grit around the float valve _- I imagine it doesn't take much and maybe it's clinging on and randomly affecting the seal. I've fitted a cheap filter in the engine bay to help prevent this. You can also see if fuel is present through the plastic.
Bill Bretherton

Only noticed fuel smell at low speed in latter.

You have your answer. 😁

20 miles would barely get the charge back into the battery from starting up (especially if you're pressing the brake pedal with those incandescent rear bulbs).

I'm not long back from a 40 mile fuel cleaning drive, about 10 miles of warm up and another 10 miles of cool down and 20 mile mix of various speed cruising and spells of WOT on a dual trunk road traffic light of traffic, served the purpose.

And I definitely went on roads that give mini-vibrations from the 'chippings' surfaces as we have plenty of those around here.

Funnily enough there's a multi-million pound property not that far from us owned by a chap that had sold (and later rebought) a company that provides some of the equipment that could do such work. The village it's in reportedly at one time at least had some of the most expensive land by square foot outside of London. I wonder if it was him or his mate that came up with the ideal of 'surface-dressing' the roads here and in south Leicestershire in the 90s. If someone laid a door mat out to brush they'd surface-dress it, and send the bill to the council, they sorted their pensions.
Nigel Atkins

Context, Nigel. I agree, further will be better, but one step at a time. This was only the second journey since it's full rebuild, and quite far enough to check what needs to be sorted. First was just to get petrol! Had to remain within walking distance of home. Next time will be further!

In retrospect, I think my error last night was assuming it was the same problem as when I was setting up the carbs, and thought was sorted with the new valves. Perhaps that did sort that problem and this is different, and caused by an alien.
Foreign body.
GuyW

Foreign body - Indian, Brazilian or Kent variety?
Jeremy MkIII

Context Guy, you can't go at low speed, and if you have a leak or are low on fuel you need to drive fast in case the tank empties before you get to where you're going. 😁

Fair on you doing 20 miles then, 6+ miles walk back, I'd always route to include pubs to phone home from and get a lift, but I do have a lot of experience of these old cars failing.

The listing before including the wheezy SU pump was also to cover the possibility of more than one issue causing the overflow. You may care to forget the tedious time I had with my carbs, I do, but part of the problem was I dismissed what I thought I'd sorted before and that there were at least one other, if not more, contributing issues to the overall problem, one of the possible issues didn't surface until much latter but with hindsight would've fitted in well as a further PITA to the main issue.

Sometimes you can be too close to something to see, if its not overflowing now leave it and come back to it with fresh eyes and thought, if you're lucky it might even have gone away and you can concentrate on the next batch of issues.
Nigel Atkins

Sometimes you can be too close to something to see,>>
Yes, exactly which is why I was asking for ideas, yours included 😁

And it does seem to have sorted itself today, but for how long?

After any major rebuild, I always start out a bit anxious which is unlike the excessive optimist I usually am. But as it clocks up the miles that concern goes and before long I will hardly think that anything can go wrong, ever!
GuyW

From bike experience...

Do the floats er... float?
Yes check float height
Is float pivoting OK on the spindle?
Lap in/polish the float valve seat perhaps - cotton bud and T-cut or similar. If new they may have an imperceptible burr.
Yes muck can get in there - doesn't take much.

Oggers

Guy,
if you can worry about something that's not there you obviously don't have enough issues on the car, let me send you my to-do-list on mine, and it doesn't include the roundtoit list or the pretend it's not there list.

I'm sure you'll keep an eye out for the leak's return and if you're like me it'll distract you from other stuff you should have been looking out for or forgotten or a completely new issue(s) will start and even more annoyingly be interment.
Nigel Atkins

Guy,

it took me more than a month to find out that the intermittent (RPM dependant) overflow was because I had a Viton needle without spring..... With the spring is was over!
See photo

Flip


Flip Brühl

Thanks Flip. I think mine do have the spring, but I am not 100% certain so I will need to check that as well.
GuyW

No rpm when the engine isn't running, so something more basic happening imo.

It could be, and I suspect it is, something that happens a lot more to others too, than is reported. Just a tiny bit of debris is all it takes, between the jet and its seat. Maybe you just have to live with it. --- Imperfect design, prone to the odd bit of flooding?

The viton seat is 'soft', a small contaminant could become embeded perhaps?
anamnesis

I didn't get to it yesterday due to sky leakage, but should today.

I know what to do - it just needs checking through from step 1 onwards. Float levels, jet heights valve seatings . . . .

The overflow rate is fairly slow. a drip, drip, drip every 3 or 4 seconds, so its not torrenting out. I think when the engine is running at speed it probably consumes this much so in effect it doesn't leak then. Though it might run rich. I will check the plugs. At lower engine speeds it probably floods the carbs, hence petrol smell, spluttery "wet" sounding exhaust note, but doesn't overflow from the vent hole. With the engine off, but ignition on (unusual situation, but that is how it was when I was checking volts and polaity for my electronic indicator flasher) then it begins to overflow and drip. To me this all points to fuel pushing past the needle valve either because of excess fuel pressure (unlikely with an original spec, refurbished electrical SU pump) or much more likely just a needle valve problem. That fits also with only one carb flooding, as Anam has pointed out earlier.


But out of interest and as a point for discussion: Is flooding more common than is reported? It seems to me that although the fuel smell at low speeds was noticable, many drivers might just think that is how old pre fuel-injected cars are and accept it. And unless they left the ignition on with the engine not running, it maybe wouldn't ever drip from the carb overflow for slight leakage situations. To me, in that situation the bigest problem is fuel overflowing internally through the jets and running down into the engine, washing the bores and diluting the oil. And you may never know!

Years ago an "old-timer" (as I am now, though was maybe around 20 at the time) telling me never to leave the choke pulled out on an stationary engine fitted with SU carbs. It lowers the jet and syphons fuel out of the reservoir, spilling down the inlet manifold, washing the bores.
GuyW

Guy

I don't recall noticing SU's flooding as a general rule even at low speeds. I had a weep from the rear SU when I started the engine recently but the proverbial tap with a non metallic instrument solved it and it behaved itself when I did a quick timing and mixture tune up.

That said I notice the H1 carbs have overflow pipes which run down past the heat shield. They have the earlier float arrangments of course which may have been more prone to leaks than the later set up.

Given the location of the carb over the exhaust manifold I would have thought the problem can't be too extensive as there would potentially be a great deal less BMC A,B and C engine powered products
Bob Beaumont

Maybe not Bob. But I was speculating that slight flooding wouldn't result in visible overflowing in a running engine and might also only then occur at low engine speeds, when many owners might not pick up on there being a problem.

That said, I am a great fan of the SU design of carb for its simplicity and adaptability. It's a superb bit of logical design.
GuyW

Just thinking out loud, re. the so-called SU float-chamber 'overflow pipes' . . . surely they should be more accurately described as 'breather pipes'?
J Thomson

Back on this as it's not right. Its no longer overflowing and dripping on the floor. But I removed the air filters and with the ignition on but engine not running, I could see that fuel is overflowing from the front carb jet and running down the carb throat into the inlet manifold. Not good!

I tried as suggested and swapped the needle valves and bodies between the two carbs. But the fault remains at the front carb. So its not the valve. And as far as I can tell the float level is correct and anyway it's the late style that are not adjustable.

I think that the only thing remaining is the seal between the valve body and the float chamber lid. I wonder if the surface of the lid might not be machined accurately. (They are new carbs and lids). I do have spare carbs from the 1275, which now has an HIF, so one thing would be to borrow a lid from the other set.

Should there be some sort of sealing washer there under the valve seating? None was fitted. Apart from possibly improving the seal adding a washer would lower the jet and alter the fuel level.

GuyW

Guy,
I'm lost as to exactly what you mean by what seals, what carbs do you have, what are the tag numbers, or body numbers, or set number - then we can all refer to the SU parts list drawing for the seals, grommets and so on.

What about trying a direct gravity feed to the front carb, or both carbs, to eliminate the pump.
Nigel Atkins

Sorry Nigel, lack of info! It's a pair of new SU carbs, that came with the car as part of the "project" that the PO had bought new from Burlen SU, apparently matched and set up for a 1098cc engine (which is what I have) There are no tags on the carb lids. Where would I find "Body Numbers"?

There isn't a seal, which is why I was asking about it. The jet body - the brass piece, - screws directly into the float chamber lid where the contact area appears to have a machined flat surface with no aditional seal. Should there be one?

I think that the needle jet and brass seating is eliminated as a souce of the leak as the overflowing fuel into the front carb, continued there even though I swapped the valves over with th e rear carb, (brass bit and needle kept together) If the valve isn't leaking and the float is floating, what else is there to go wrong?
GuyW

IIRC Colin's set of carbs weren't a match to themselves let alone each other, this was found by the various numbers on or under/inside each part. This shouldn't be the case with yours but if any numbers don't match then you know something is at odds with the accepted history. My new carbs came with model number tags on the float bowl lids.

AFAIK there's no seal between needle seat (5 top) and lid, the seat is a BA I think but will go in with an imperial AF socket, I forget the size now, but should snug down with either type of socket.

Did you try swopping over individually the seat (5 top), needle valve (5 bottom), float (6) and float pin (25) to break any pairing or combination of these parts that might cause issue when combined.

Once the lid is on you can't see if the float is floating, perhaps a kink, bend rough patch on the float retaining pin (25) might hold the float down out of sight even though it seems to work fine when tested out of situ. I've had other things work fine until you put them back together and have them doing their job, or more accurately, not doing their job properly.

One of my float pins (25) was to my surprise very loose, it just fell out when I turned the lid over to what I thought would be a struggle to pull or push it out. Once the lid is on the pin is held by one end at least.

FYI -
. '62-'63 carbs AUD 73 (f & r)
. '63 on AUD 136 (f & r) same as 1275

(if I remember) I'll look at my carbs for lid numbers(?).

Photo and numbers added to text.



Nigel Atkins

Can you check the fuel pressure just to make sure it's correct and not excessive. IIRC the fuel pressure is solely governed by the spring in the fuel pump, the solenoid just being used to retract the diaphragm and draw in more fuel and once released the spring is what applies pressure to the diaphragm and therefore fuel.

I have had the odd Amal (Burlen) part which was not done up correctly but this was not a carb but it still shows a lack of attention to assembly detail on someone's part at Burlen in recent times.
David Billington

Edit:
Once the lid is on you can't see if the float is floating, perhaps a kink, - bend or rough patch on the float retaining pin (25), or float, or lid buckles - might . . .

David,
I put to try a gravity feed to eliminate the pump - because I thought it'd not be appreciated for me to question the venerable SU pump but you have, I think you're the first person I've ever seen put there's ever been a problem from SU - are you sure it wasn't you that caused that problem or the supplier or delivery service "you're the only person to have had this problem". 😉
Nigel Atkins

Nigel,

A quick calc gives 16' for a head of petrol to generate 5psi. IIRC that's the max for an SU though lower is better, 1.5 to 3.5 psi I have seen mentioned as a good range.

The Amal item was a gas injector http://amalcarb.co.uk/amal-gas-injectors.html and I've seen a few delivered in pristine packaging well wrapped where the gas jet was screwed in finger tight and could be easily undone with ones fingers, not ideal IMO when dealing with a flammable gas although it should be checked when the injector is checked for fitting leaks as the 2 gas entry ports have to be installed by the user to suit their desired configuration.
David Billington

I thinks it's not likely, even impossible I'd think, that the pump pressure is excessive.

Reasons.
1. As you say, the pressure is set by the 'volute' spring. This is the spring that pushes the diaphragm, that pushes the fuel to the carbs on the outlet side of the pump. It can't vary in strength, and no su pumps (even the so called high pressure) are higher than 3.8 psi.

2. An incorrect spring installed from new? If so and the pressure is excessive, then why an intermittent fuel overflow, and why only the front carb?

Guy your observation about the fuel flow over the bridge is interesting. Is that constant, or pulsing? My understanding is that can happen if the fuel level is too high in the bowl. Normally the fuel sits just below the top of the main jet when the choke is closed. 'Low pressure developed over the bridge draws the fuel up. Could you have set that carb too rich, simulating a choke open condition? But even then, wouldn't the fuel still sit below the bridge, until drawn up by low pressure, and only when the engine is running of course?
anamnesis

I've just had a quick look on my carbs, the only marking I can see other than the tags is 'AUD' on the top of inlets on both bowl lids. I thought there were more markings but I tend to forget, or blank out, details of car sorting miseries, no, I mean, great joy and satisfaction of sorting the problems.

I've got an electronics repair kit that would also sort an SU pump - 2lb lump-hammer and 6" nail. 😁
Nigel Atkins

I THINK it is fixed, though don't want to tempt fate!
I took the lid off my spare carb set (Nigel, numbers are on the underside of the casting) ready to do a swap of complete lid/float/valve assemblies. Comparing them in good daylight i noticed a shadow line where the valve body screws into the lid of my problem one, but not on the other one. Removing the valve I found a little burr of alloy on the machined surface. Once I had scraped that flat and tightened the jet back in it seems to be holding.
I have left the ignition switched on for 30 minutes (disconnected coil LT wires) and both carb throats have remained dry this time.
GuyW

Sounds good,

If you want to lower the valve body ISTR in the overhaul kits were some fairly soft aluminium washers - then using a socket do up the jet to a good 'tightness'. I don't think lowering it by a washer or two will cause a problem and may give a bit of 'headroom' if the needle is cutting off a bit late.

richard b

I think its ok as it is now, Richard.
Can someone point me in the direction of a RELIABLE source of ethanol proof fuel hose. I believe it is too easy for unscrupulous suppliers to print the magic numbers on hose so it needs to come from a known good supplier!
GuyW

Gates Barricade fuel injection hose---
William Revit

Echo that. I've had gates barricade on mine too for the last 4 years and no signs of deterioration at all.

But here's a mystery, which may sound unbelievable but is nevertheless true. The original braided mesh covered rubber hose that feeds the first carb, and the link hose that feeds the second carb, are the hoses that have been on my Sprite for at least 30 years. Not only have they not rusted, the hoses havn't perished, and they haven't succumed to ethanol either. Although I must admit, I use Esso 99 e-free now, but for a few years I was using e5 petrol. Was the rubber used yonks ago superior and already e resistant?
anamnesis

Thanks Willie.
I have mesh encased fuel hoses as well. But sorting the other problem I find that the rubber caps over the ends are begin to crack and deteriorate already. I didn't check the hoses inside the mesh but I suspect they are also poor quality too.
GuyW

Gates is a good name to go for based on my fan belt experiences.

I think most reliable names are fine for modern fuel hose, I've used Goodyear fuel rubber hose before with success.

I've lifted this from a recent post of mine to deal with the escalating numbers some like to see printed on the fuel hose. Note I gave Holden merely as an example. -

"The VW (special?) 5.6mm is Codan SAE J 30 R 9 (high pressure 10% ethanol at least) FKM - NBR - CPEFUEL HOSE 5.6mm [55L12(?)].

There's a lot of worry and concern about getting the highest R number but it's a bit like your amp going to 11 rather than 10.

I'm using R6!!

A quick look and Holden Vintage & Classic 1/4" bore Rubber Fuel Hose - SAE J30 R6 and state -

"Resistant to all modern fuels including petrol containing ethanol up to 15% (E15) and even E-85, but not for bio-diesel. Reinforced with two spirals of synthetic fibre and covered in black Hypalon. Good flexibility. External diameter 13mm (Use hose clip 015.916). Maximum working pressure 50 p.s.i.. Meets SAE J30 R6 Specification. Stocked on the roll and sold by the metre length." - https://www.holden.co.uk/p/1_4_in_bore_rubber_fuel_hose_sae_j30_r6

Course they could be wrong, not bothered or even lying, you'd have to ask them."
Nigel Atkins

On Nigel's recommendation I ordered that J30 R6 hose from Holdens. Their site lists it as suitable for up to 15% Ethanol. Seemed like a good company.

What has been sent may be to that specification, but doesn't carry the SAE code. It's just numbered 3123, whatever that means. I have e-mailed them back to check what this stuff is that they have sent.

In the meantime, trying to check what this other number means I came across this article which makes interesting (to me) reading.

http://tinyurl.com/yhyn99je

He says that the R6 specification is about the minimum, but that "for classic vehicles, J30/R9 fuel hose has become widely accepted as the best all round general replacement" (2016) when Ethanol is a component of the fuel. Apart from the unknown number, have I ordered the wrong stuff.
(1/4" Barricade hose was out of stock at all the sites I tried)
GuyW

Demon tweets have this :-

https://www.demon-tweeks.com/uk/mocal-sae-j30-r9-high-pressure-rubber-fuel-hose-2008532/
richard b

Thanks Richard. That is a 7.3mm hose so a little oversize for my car. But anyway, at the moment I need to sort out with Holdens what they have sent. Its manufactured by Codan (same as that Deamon Tweeks one)

I just checked on the Codan website and downloaded their specification sheet.

For my 3123 hose it just has a blank against the Standard: line and doesn't mention an SAE rating. But it lists 3122 as J30 R6, R7 and R8 and 3133 as the R9 spec one.
GuyW

Guy,
I know this internet shopping is a bit new for our generation but if you look again and look at the option drop down there are all sizes including 1/4” which I thought was the correct size ?

R.
richard b

Yes, Thanks Richard. I realized they probably had other sizes, but I still want to sort out what it is that Holden's think they have sent me, and that I have paid for!
GuyW

Guy,

From https://www2.codan.com/sites/default/files/file/Codan%20Industrial%20hose%20catalogue%20july2016.pdf 3123 doesn't list any standard in the spec details whereas 3133 does list R9. I didn't want to upload the PDF as it's 200 pages. Might have to copy and paste the link due to the embedded spaces.
David Billington

Yes, that' the Codan pdf data I quoted in my message earlier at 20-28
GuyW

Guy,
I think you have done the right thing to ask Holden what they have sent you. The link I put up clearly has -

"Resistant to all modern fuels including petrol containing ethanol up to 15% (E15) and even E-85, but not for bio-diesel. Reinforced with two spirals of synthetic fibre and covered in black Hypalon. Good flexibility. External diameter 13mm (Use hose clip 015.916). Maximum working pressure 50 p.s.i.. Meets SAE J30 R6 Specification. Stocked on the roll and sold by the metre length." - https://www.holden.co.uk/p/1_4_in_bore_rubber_fuel_hose_sae_j30_r6

Just to be clear, you have misunderstood my post I was not recommending Holden, just giving it merely as an example, I have never bought anything from Holden, far too expensive and snooty company type for me, I have visited the place once on the way back from Wales years ago after they took over Bygone Era flying jackets but they had the price too high for me by then.

I've mentioned Frontline (Developments) a few times but not ever recommended them.

You could try contacting Codan as David's put it's a bit of a strange entry in their catalogue.

I use R6 and have done since having piss poor rubbish rubber 1/4" fuel hose but not from the usual suspects on these occasions but various independent motor factors. The current stock I have on my midget is just from ebay suppliers, it has the R6 marking and I hope it's genuine but certainly not at £14-£16 a metre for the R9 stuff.

Guy, I do have short lengths Codan R9 5.6mm but I read that it's so tight a fit that any protection would be scrapped off the inside of the hose, I've no idea if this is bollocks, you'd have to ask Codan, I just thought it's too tight to the 1/4" stuff on the car with all the farting about (and you know I don't mean farting) I always end up doing on my car, certainly proved so with the carbs 'fun' last year.

Guy, yours for free if you want to try them two (used) lengths, marked up as - CODAN SAE J 30 FKM - NBR - CPEFUEL HOSE 5. 6 mm 55L12 (which I didn't see in the catalogue either but I only looked in the index for 55L12)

. two foot ten and a quarter inches

. one foot nine and three quarters inches.



Nigel Atkins

For the J30 R6 Hoseworld has a good price https://www.hoseworld.com/copy-of-fuel-hose-bs-au-108-c4-l4-r.html although their shipping can be expensive in the order of £12 as IIRC they use UPS. Makes Holden seem expensive but it depends on shipping/packing costs. Demontweeks must be very proud of their R9 at £14.40/m for 1/4" hose.
David Billington

I've bought from this supplier before (R6), might be on the Midget now, can't remember, might be the 8mm (to my non-SU pump), Nectar points and TopCashback on ebay, plus supermarket points if I pay using the credit card even if through PayPal.

https://www.ebay.co.uk/itm/260686371844


Nigel Atkins

The Mocal stuff from Demon Tweeks I linked above is also made by Coden:-

'The Mocal SAE J30 R9 high pressure rubber fuel hose (manufactured by Codan for Mocal) is the highest SAE specification petrol fuel hose available. The outer part of the hose is made from nitrile rubber with a thin flexible layer of fluoro-elastomer in the bore, which provides an exceptional resistance to sour petrol plus methanol and ethanol additives. The hose has a working pressure of 100 psi and is suitable for use with both carburettor and fuel injected cars.

Suitable for petrol, diesel, bio-fuel, ethanol and oil
Has a working pressure of 7 bar (100 psi) and a burst pressure of 62 bar (900 psi)
Rated to 140 degrees c working temperature with intermittent 150 degrees c'

It even notes O.K for Bio fuel.

R.
richard b

No problem. I am not at the moment looking for another supplier. I am dealing with Holden's first, and awaiting their reply. I bought a hose from them listed as J30 R6 and similarly identified on their invoice. It is also described as suitable for up to 15% ethanol fuel which would be fine. But that doesn't appear to be true for what has been sent. They now have the opportunity to correct what they supplied so I will wait for their reply.

Nigel, I did take it as a recommendation. I clearly said "Can someone point me in the direction of a RELIABLE source of ethanol proof fuel hose." Even included block capitals. Your subsequent message, states " I am using R6", followed by your reference to Holden's, even including a link to this specific product. If this wasn't responding to my request for a RELIABLE source, I don't know what you thought you were messaging about!
Not that it matters. I am quite happy to live with my own decisions, so there's no need for you to squirm. 😆
GuyW

Guy,
I'd be surprised if the hose isn't to spec and fine to use, I couldn't recommend Holdens or the hose as I've never used either.

I am sorry Guy, I didn't make it clear, the first part of my post was to deal with your enquiry -

[ Gates is a good name to go for based on my fan belt experiences.
I think most reliable names are fine for modern fuel hose, I've used Goodyear fuel rubber hose before with success. ]

And the second part was rushed, sorry, as I knew I'd recently put something about fuel hose and the R numbers and it was to explain the R6 and R9, but it did include -
[ I've lifted this from a recent post of mine to deal with the escalating numbers some like to see printed on the fuel hose. Note I gave Holden merely as an example. ]

and [ Course they could be wrong, not bothered or even lying, you'd have to ask them. ]
Nigel Atkins

Its really OK Nigel. No need for any sort of apology!

The real issue is that the Holden site lists the hose that I ordered as J30 R6 Ethanol resistant up to 15%. And the invoice sent with it also lists that specification. Its just the hose isn't printed with the SAE number but has the manufacturer as Coden and their reference 3123. And the pdf from the Coden website makes no mention of the J30 R6 or ethanol resistance in the specification listed for that particular product. Their R6 hose version is one digit different, 3122.
Its most likely either Holdens have recieved the wrong stock or have sent out the wrong one. I messaged them last night with the details, but as yet no reply.
GuyW

It's a mystery as the Codan catalogue has blanks to the standards and I guess the image Holden use for it is just a stock photo of fuel hose.

Codan show the 3122 hose as -
"Flexible, black hose for leaded and unleaded
petrol. Good ozone resistance. Resistant to oil
spray in engine compartments. For fuel pipes in
cars, lorries, lawn mowers, garden cultivators, etc.
The hose is based on SAE J30 R6, R7, R8, R11 [1998]
Please contact Codan for further information"

You are right to check though, I think I've put before about picking up a brand new British built car from the makers to discover far from home and factory that the fuel filter leaked and the rubber hose to and from it wasn't petrol resistant.

Confirms the not being able to recommend because Sod's Law as soon as you do an excellent product and/or manufacturer suddenly becomes a lot less so. Then there's the intermittent or batch quality which can bring lots of good and bad reviews. And I suppose sometimes there's where something that was bad becomes good.

The sort of made me laugh. 😊
Nigel Atkins

Yes, that Codan 3122 IS their J30 R6 version. As well as in the spec details it is titled that way as well.

What I have is the 3123, which doesn't specify and doesn't carry a title in the Codan entry.
GuyW

Thread high jack alert !!!

My HIF6 has the opposite problem - currently not being run much due to domestic issues.
About a month ago the car cut out just after firing up - checked pump- all good - gave the carb a bash - no go.
Stripped carb off -( HIF bottom float chamber ) put it back together as no visual issues with needle assembly - fired up OK.

Tried today same issue - gave it a thump and then connected a 60ml syringe to the inlet and pumped/ pulled a few times - reconnected pump - fired up immediately!

So why would the valve stick as seats look very good ?
The carb was rebuilt only about 1000 miles ago.

Sorry Guy about the drift !

R.
richard b

Yes and based on R7, R8, R11 (1998) too.

I got called away before editing and missed posting the images to distinguish between the two very similar number products (Sod's Law the numbers are so similar) but I'm not sure if that's relevant to Holden stock. Similar numbers but different materials used.







Nigel Atkins

As those are just CAD images, I don't think they help much.
Here is a photo of the actual Codan pipe that Holden's supplied.


GuyW

My photos were to compare materials and standards, yours to twist necks.

On the hose after the 6.3 I think I can see SAE J30 R6!

No news back from Holdens then, if you don't hear tomorrow then how about contacting Codan.



Nigel Atkins

It occurs to me that the phrase "normal and lead free" is rather odd, at least for the UK and European markets. Lead free IS the normal these days, and has been for a long time!

They could alter the label to "normal and E10 petrol"
GuyW

Without a confirmation of suitability for use with ethanol containing petrol from Codan I wouldn't use the stuff, I expect they had a reason to not add any detail in the specification item for the 3123.
David Billington

Sounds like it could be for a specific rather than general market or other than Europe (and UK), even the green colour writing is odd to me.

I didn't look other than the index but didn't see in the catalogue the (VW, special?) SAE J 30 R9 FKM - NBR - CPEFUEL HOSE 5.6mm 55L12.

BTW the two foot ten and a quarter inches length of it I have is unused.
Nigel Atkins

This is something which should be so straightforward but seems shrouded in mystery.

Is this any help?

CODAN 3133 which seems to be ethanol and oxised sour gas (sounds grim) proof (1st image).

Available from here at £12.79 a mtre
https://www.vehiclewiringproducts.co.uk/p-1295-rubber-fuel-hose-ethanol-resistant

and finally an image of the hose.





Jeremy MkIII

Only thing, the Vehicle Wiring Products link doesn't show it as available in 6.3mm.

Nigel Atkins

Thanks Jeremy.
Actually, you are right, its not complicated at all.
As far as I am conerned I know what to get and where to get it, who manufactures it and what the specs are. My current issue is that I ordered what was advertised as a specific standard and what was sent appears to be something different. I e-mailed them on Wednesday evening about this and am still waiting for a reply.
GuyW

Can we not assume, then, that the hose from Moss is ethanol resistant? That's what I've used - the stuff with the metallised outer.
Bill Bretherton

Guy, I was not being critical of you but of the industry. It is more difficult than it should be to buy ethanol proof hose, there is quite a debate on air cooled VW forums about it as several vans have gone up in flames despite having supposedly ethanol proof fuel hose.
It's surely not difficult for sellers to say their fuel pipe is or isn't ethanol proof and I'm a little wary of the phrase 'ethanol resistant'.
Appreciate your concern is with what has been supplied. Any news?

Nigel
you're correct, there isn't a 6.3mm hose listed by that seller but it is manufactured in that size
https://www2.codan.com/node/28273
and is available from here
https://www.ebay.co.uk/itm/6-3mm-1-4-ID-CODAN-SAE-J30-R9-Petrol-Fuel-Hose-Ethanol-Tolerant-Gasoline-Pipe-/254656405760
I'm going to try some and will let you know how it fares.
Jeremy MkIII

No, I didn't think you were being critical, but commenting on the length of the thread over, as you say, a simple enough matter. And no, still no response from Holdens, though we are part way through a BH weekend.
GuyW

Dog 'n bone 'em Guy. It annoys me when companies don't get back to me after I spend money and have a complaint.

As you say, BH, and possibly staff shortages due to pandemic, plus rush of additional problems due to increase of business as restrictions ease. Or, just ignoring you because they aren't interested; which seems unlikely for a well known firm.
anamnesis

Jeremy,
VoltsBolts, that's the supplier I saw for the 5.6mm originally, somebody with a VW (camper?) association put up a link to an article of VoltBolts leading on to the hose they sell.

I've still go the used and unused lengths of the 5.6mm.
Nigel Atkins

Despite penetrating three layers of email acceptance I've yet to receive a reply from Bosch about those rotor arms.

However even without following up I did get a late email reply from Demon Tweaks to my email to them and they apologised for their delay in responding so fair play to them.
Nigel Atkins

Update: I rang supplier (Holdens) Gave him the details about the problem. Friendly response agreed there was a problem and said he would check it out and ring back, which he did. Apparently Codan had supplied this different spec hose and confirm that it isn't to the J30 R6 spec. (which we knew, didnt we!). So they have ordered more of the correct stock from Codan. But apparently it us in short supply so he couldn't say when it was expected. He offered a refund instead, including the P&p and doesnt want the old hose back.

Reasonable outcome I suppose, except I am back to square 1. Luckily, its not an urgent matter.
GuyW

And now I have a fuel tank leak. :-(
It was dripping fuel yesterday from the tank, but tracing it back it seems to be originating from the top. It's a new steel tank. I don't think it is from the flanged seal where the top and bottom halves are welded together. Without dropping the tank I cannot be 100% certain but I think it must be from the tank sender unit cork seal. But given the position on top of the tank would that leak?
GuyW

Hi

Is the following Cohline fuel hose any use: https://www.merlinmotorsport.co.uk/p/rubber-fuel-hose-din73379-rated-by-cohline-per-metre-2134
(Or https://www.merlinmotorsport.co.uk/p/cohline-yarn-fabric-braided-fuel-hose-din73379-per-metre-2122)

https://www.glencoeltd.co.uk/cohline-fuel-vacuum-hose/sytec-competition-fuel-hose-low-pressure/cohline-2240-r9-specification-rubber-fuel-injection-hose-6-mm-push-on-e85-compatible/
(https://www.glencoeltd.co.uk/cohline-fuel-vacuum-hose/sytec-competition-fuel-hose-low-pressure/)

https://www.cohpro.com/cohline-fuel-hose#

Guy - is this some odd tank venting/pressurisation issue? (or end of the honeymoon period with the car!)

Cheers
Mike
M Wood

Thanks Mike.
Fuel pipe no longer an issue.
I thought fuel leakage could be a tank pressure issue as it was on a hot day, and a full tank. Or maybe just that I overfilled the tank? Or is the sender unit vented?

Not a honeymoon issue as they only needed the car for the day and it behaved perfectly, - it's a walking holiday for the rest of the week.
GuyW

If you've got a detachable filler neck could it be the rubber joint hose or clips?

Don't panic Mr. Weller. Don't panic.

I had a leak which I thought would be from my new fuel tank or more likely the rubber sealing ring for sender, both requiring the tank that was full to be emptied and tank dropped, again. I decided the best way to empty the tank was to drive the car.

As the leak went away as the tank emptied I decided I needed to brim fill it again to check for the leak - but the leak had gone away never to return.

Why it started, stopped and hasn't returned I don't know but it was definitely petrol leaking from the top of the tank area. Perhaps the seal contracted and/or expanded - I don't know and don't care unless it returns and so far it hasn't after many fills up to top of filler neck.

I'm not saying yours will be the same but it might, if the leak stops as the fuel level drops it might be the cork seal, if so you could try adding a gallon of petrol at a time to see if the tank needs to be full for the leak.

ETA: Guy - Mike meant honeymoon period between you and the Sprite.

Nice paint colour for nuptial photos.
Nigel Atkins

Yes, I like the solution of "do nothing", Nigel.
It's not leaking at the moment so I will just wait and see.
And yes, I did pick up on Mike's meaning as well. 😁
GuyW

This thread was discussed between 15/05/2021 and 07/06/2021

MG Midget and Sprite Technical index

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