Welcome to our resource for MG Car Information.



MG parts spares and accessories are available for MG T Series (TA, MG TB, MG TC, MG TD, MG TF), Magnette, MGA, Twin cam, MGB, MGBGT, MGC, MGC GT, MG Midget, Sprite and other MG models from British car spares company LBCarCo.

MG Midget and Sprite Technical - Head gasket failing?

Hi folks
I noticed that since the radiator failed spectacularly the other week, the engine has become slightly noisy, and it seems there is a leak in the exhaust that can be heard in the manifold area. I got my beater half to block the exhaust pipe with a cloth bunched up in her hand, and the exhaust is definitely leaking up front, though quite where remains to be seen.
I have also noticed over the last few days a small trail of coolant, picture below. This at the front left corner (passenger side) of the engine, and seems to be from the head joint. I did try torquing down at the weekend, some of the nuts were only tightened down to about 30lb foot instead of the 50 required. The seepage (leak is slightly too strong a word) is still there.
What do people reckon? Replace the head gasket?

On a more positive note, I have found the reason behind the fast tickover and seemingly advanced ignition problem that I mentioned a few weeks back. A new distributor had been fitted, along with a new cap by the previous owner, non-genuine Lucas. There is a rotational "play" in the cap of about 2 degrees, and another degree play in the rotor arm. I had removed the rotor arm when parking in an iffy area a few weeks back, and hadn't noticed the sloppy fit when replacing it. I therefore retarded the cap and rotor in relation to the spindle, and it made a world of difference!

Dominic Excell

and another pic of the offending drips

Dominic Excell

:- ( Could be the beginnings of HGF as you say. Is there any sign of emulsifying oil under the oil filler cap? That front left corner is also where the oil feed up to the rocker shaft comes up and water leaking there could be contaminating the oil as well. Presence of mayonnaise would confirm it.

But I wonder if the two faults are connected? If the manifold is loose perhaps exhaust gas is blowing out under the manifold joint and water is condensing out of the exhaust fumes and dripping down the block? Could be exacerbated by this damp, mild winter weather. Have you checked the manifold nuts for tightness?
Guy Weller

Im thinking condensation... I like guys approach, I hadnt thought it like that

Easiest way to tell is hook up a vacume gauge to the intake manifold....that will tell all quickly.

Prop and the Blackhole Midget

Here is a good easy and fast read on how to read a vac gauge ....I googled it,

Personally I perfer boost gauges because they can read both vacume pressure and positive pressure....soooo double the utility for the same dollar

A vac gauge able so you can see from the vac gauge chart of what different spec. And differant types of vibrations Mean


Prop and the Blackhole Midget

No emulsion, that was the first thing I looked for. The rocker cover was off at the weekend while I torqued up the head bolts and reset the valve clearances, no emulsion anywhere.
I wish it were condensation, but it tastes of antifreeze and has a blue tinge, so coolant it is.
I'll test the pressures tonight, I have just a bog standard pressure tester that screws into the sparkplug holes.
Manifold nuts were ok when I checked a few weeks back.
Dominic Excell

you are maybe too careful to miss this, but I have been caught out before by coolant leaking from the top hose where it connects to the thermostat cover. And trickling down to get caught and diverted along the joint line between head and block. The wind from the fan blowing the dribbles back so they appear down the side of the block.

If your compression test still gives good readings, then I would just add some Radweld or Ceelit for now, and keep an eye on it. It will either get worse and become clearly apparent what the fault is, or it will fix itself.
Guy Weller

And while you investigate. --- "I got my beater half -- ", you might think about going to a domestic viloence center. Many men won't report this sort of thing, but you should. Just tell her straight, it has to end ;).

I can't quite remember the circumstances of your rad failure, but if the engine overheated significantly, and with those symptoms, I too would suspect hg failure. I wouldn't pull the head just yet, but I might well pull the manifolds for a close look to eliminate that gasket at least. And if it's good you can re-use it.
Lawrence Slater

When my HG failed between cylinders 2 and 3 - which it did fairly frequently, it was always accompanied by the blowing sound described above. Indeed, this was the way it was always initially diagnosed.
Not sure what the technical explanation for this would be - if there is one, it never combined with any sign of a water leak though.
S G Macfarlane

the exhaust manifold gasket when it start to go or goes can be noisy, sounds like something a lot more serious, from a flapping bit of metal to something very noisy in the engine - could also be something on manifold too

I think it's worth a try to retorque the head as you're found some loose and your a cautious chap so you'll keep a very careful eye on things so if that didn't work your know before any more damage is done

these are drips that remain on the engine so it suggests a leak that continues after the engine cools - the only thing I can think of for the drips there is the coolant coming out of the connection from the heater and running down the metal heater pipe to drip off nearer the front of it

this is another good reason why I use 4-LIFE as it's easier to trace the source of leaks with it, the pink stands out and it leaves a good trail or pattern to follow plus you can tell by it being wet or dried when it leaked a lot more so than with usual coolant

on the rotor arms, good ones are a very tight fit but I've found the dissy caps I've had have all had an element of twist to them
Nigel Atkins

How low on coolent ??? Have you replaced very much???

Prop and the Blackhole Midget

Thanks for the input chaps
I'll do a compression test, and check for coolant seeping from the heater hose. Haven't had to top up Prop, negligible loss, probably no more than a tablespoon full lost.
I'll pull the manifolds Nigel, if nothing else I can see if there's any soot marking where exhaust is escaping. Have loads of good old manifolds left over from my Morris Minor days. Just the one copper HG though.
Will report back later tonight if I can get away with it with my better half..... (and no Lawrence, she hasn;t beaten me yet, except at Monopoly!)

Dominic Excell

Lawrence, the rad simply blew the metal pipe that connects to the hose to the thermostat cover out of the top rear face (1275 crossflow). Seems that the Chinese solder wasn't up to high speed pressures from the 700 mile-ish trip over the long weekend. It blew spectacularly after only 2 miles on a cold day, enveloping the car with steam. I refilled the rad and wedged the pipe back in, and limped the 2 miles home, with the temp gauge getting almost to the 212 deg mark but no higher. At no time did the engine sound stressed or unwilling from overheating.
I wouldn't have thought it would have caused a problem as I kept the revs right down to about 1500 max. I may however be wrong and am now paying for it!

Dominic Excell

Dom wrote...

""Prop, negligible loss, probably no more than a tablespoon full lost.""

(I had asked how much coolant was lost and how much he had to replace)

If you only lost a table spoon of coolent, id say thats a strong argument for condensation on the block and head....a table spoon of coolant could have easily gotten lost in the brass expansion tank

Prop and the Blackhole Midget

Just a thought....

Are you sure the problem isnt a case of cabin fever hallucination...

Its more real then you thank....ive heard stories of people replacing there home fuse box because they belived there light bulbs got dimmer.

I would be more concerned about the dissy being worn, before the leaking coolent head gasket you looking into...

The play you mention in the dissy could be a case of needing a rebuild, esp if there is significant play in the plate that holds the breaker points.

on the shaft play... is that actual worn shaft play or is that the normal play of the dissy gear meshing with the camshaft gear...some play is expected in the gears meshing

Prop and the Blackhole Midget

was the engine cold or warmed up, when the rad pipe broke off ?

If the engine was cold or room temp...and you only traveled 2 miles at 1500 rpm...(barly above idel).... or as you said, it was really cold out side and the new coolant you refilled the engine with was also cold so that it would take the stat a while to warm the engine back up

Then I cant imagine there being an issue.. I wouldnt recommened it, but I got to belive your okay. The fact that the gauge read 212 with still room to rise on the gauge face and the gauge temp never dropped back down to 180, 160, 120ect ect.... is a good thing in my opinion because that indicates there was coolant in the engine....if the temp went high then back to real low instead of continuing higher, then that would mean there was no coolant inside the cly head at the coolant sensor location... meaning just hot air/steam, the senor cant read air and steam temp very well, and will read it a lot lower then actual temp, ...if its reading 212, then I got to belive the gauge reading the temp of the liquid coolant. Not steam/air inside the cly head

That said... remember I am prop, so your engine is probably toasted....hahaha
Prop and the Blackhole Midget

Prop, I tasted the water on the engine, it was definitely that bitter-sweet taste of glycol!
Good news however, just done a compression test, albeit on a cold engine, but the pressures were all identical at 150lbs.
I also managed to tighten the manifold nuts slightly as it was cold. Lets see what tomorrow brings (apart from sh*te weather!)
Dominic Excell


The rad was a catistrophic failure, im sure your entire engine was coated in glyco coolant.

Id be very worried about you if you licked your engine and DIDNT get the sweet taste of takes alot of washing to to remove glyco suger residue

I have washed my hands several times after handling coolantand still had the feel of sticky residue.

Nigel,... hurry up,

someone may beat you posting about the deadly dangers of licking up glyco coolant...hahaha

Wow... 150 psi across all 4 clyinders.... yepp, cabin fever hallucinations is my diagnoses.

Im feeling very positive and up beat on your engine situation

Prop and the Blackhole Midget

Comments crossed in the post Prop.
Dissy is fine, it was just the less than perfect fit of the rotor arm on the spindle, and the cap on the body. All else is fine. I just need to make sure that the rotor is backed off as far as poss, probably less than a millilmetre rotation, and the cap advanced (or the other way round, can't remember without actually being at the engine)
The engine was coolish when the rad broke, Normal suburb driving of 2 miles, at 2- 3 thousand RPM. It was the return journey that was so "gentle". I agree about the gauge reading, still water there.
I suppose it's just about possible that the coolant appearing is some that had sprayed into crevices when the rad broke, as it did soak the engine bay somewhat. Pointing straight at the manifold hence the steam.
Will monitor it anyway.
Dominic Excell

Sure... monitor it,

but... im not a monkeys day time beliver....Im fully time beliver on this one :-) I do belive your golden and good to go

Are you saying the rotor bug inside the dissy has side to side play on the dissy shaft ? It should be rock solid no play at all, if so, id start start looking for a defect / crack and asking why and get a new one

The cap and dissy body has some slots that finger themselfs togather and the cap has an inner ring that fits inside the top of the dissy ... there should be no play if the cap and dissy are fitted correctly

Are you sure the cap is not hanging on the wires that come thur the gromet, or that the gromet is not installed correctly causing the cap to not attach securly.

Prop and the Blackhole Midget

Yep I agree Prop - good to go. Just need to cure the blowing exhaust.
Re the dissy - no not side to side but rotational free movement of the rotor against the spindle. The key is a little too narrow for the slot in the end of the spindle. It's a tight fit, but can be varied by hand! Cap likewise, slot in cap being too big for the key on the outer edge of the seating of the dissy block. Again, not much and when clamped in place, the rotational forces tend to keep it in place. The cap otherwise fits securely. One of these chinese dissys I think! Still it works well enough, good smooth and even tickover.
Dominic Excell

Hmmm... im not liking your dissy set up...

It dosnt take alot to to retard or advance the timing 2-3 degrees....the fact that you can rotate both the rotor and the cap, is scary to me...esp if your already at 10 imagine that just centrifiacal force alone could move both the cap and the rotor just by normal driving if you can easily move them currently by hand/finger...then consider the rotor tip makes connact with the 4 terminals inside the cap...thats a lot of movement of the timing....depending on the amount of play.

Something like that can really play havoic across the board, to over heating, pinging, hipknocking, ignition detentation, running on after the ignition is shut off, burnt plugs, poor fuel economy, and a whole host of issues beyound what ive mentioned. at the very least it will drive you to madiness tying to diagnose a long list of minor issues

When you say this is a china made dissy, is it something other then a factory orginal lucas 23D ?

A 2nd thought i have is the 25D was a popular alternitive to the 23D dissy with minor modification....I dont know if the rotors and caps are interchangeable...but something worth looking into....they could be just a close fit (guessing), but they do look very similar... (using my eyeballs)

(I may have 23 and 25 reversed... sorry)
Prop and the Blackhole Midget

Quite a tight fit Prop, the mechanicals won't shift it at all so no worries there. The rotor arm would anyway try to move against the stop, without success, likewise the cap. OK, if I ran the engine backwards it could gradually shift the timing. It's a 23d look-alike (without the vernier adjustment) but as a 1970 build 1275 it should actually have a 25d with the adjuster. Works well enough with electronic ignition, certainly good enough to run on while I find a good "proper" one in due course. It all runs very stable.
Dominic Excell

Well Thats good to know... sorry for any worry ive caused you, its one thing to read about an issue half way around the planet vs. Actually being there feeling and seeing the suspected deficiant part

Im glad it will work out for you, but yes china makes some real spin off doessys, ive came across a few poor fellows that got shanghide buying the webber look a like knock offs on I can only imagine the difficulties with a lucas knock off copys made in china.

Just a tought... check with peter burguss about the 123 tune dissy, ... buy from him you get his personal help and insight for installing and set up....definatly worth the extra pocket change you save buying thur ebay drop shippers

Plus the 123 tune has 16 preset curves, plus.the curves are completely adjustable with a lap top, so no mechanicals and springs to loose down the open oil filler hole or pop into your unprotected eyeball at high speed, only to watch it bounce along with your one good eyeball into the opened oil filler hole and down into the pushrod hole....haha

Prop and the Blackhole Midget

Ha ha Prop, do that twice - losing an eyeball and you'd need to find a set of braille dials. Probably get them on ebay....
Dominic Excell


The 23d had no vac advance, 25d had vac.
23 was used in Cooper S and some early 1275 midgets (66-67).

richard boobier

Oh thanks Richard, getting myself muddled, maybe it's a 24d? Can't remember without looking it up! Looks the same as the 1965 Morris Minor type, though with the plastic vac pipe, rather than the one used on a 1989 Mini 998.
Dominic Excell

now you see why I occasionally hint at having a decently made rotor arm and even offer a suggestion of a decent supplier

it used to be reasonably common to see reports of owners having running problems, sometimes difficult to pin down, that in the end came down to poorly made rotor arms
Nigel Atkins

The other advantage of the 123 dizzy is that the cap is a Bosch fitting, which fits nice and snug.
G Lazarus

Indeed I do Nigel, that'll be part of next year's upgrading. This one works well enough for now though, tickover like clockwork, now that I've deduced what the problem was.
Quite tempted to go the way of points and condenser - still have a stock of old unused ones from my Morris Minor days. Was quite adept at setting it up to the exact dwell angle. Managed to get a newly run-in engine to tick over at 250 rpm on the dot. It would tick over all day at that speed too if required. A bit easy to stall moving off if not careful though!
Dominic Excell


Some thoughts.. The root cause of leaks and possible HGF has perhaps yet to be established. I would venture that your earlier difficulties with the timing would have run the engine hot - if advanced too far - precipitating the resultant leaks and other issues seen. The fact that you subsequently retarded the timing may have come too late.

I have found that timing needs to be spot on, then retarded just a tad - I have 123 - to get a very slighly rich mix, and thus running very slightly cooler. Naturally make sure your mix is correct before doing this.
Mark O

Sorry to enter this conversation at such a late point, but reading through the posts, I cannot understand how a loose rotational fit of the dissy cap or rotor arm could affect the ignition timing? As I see it the function of these two parts is to distribute the HT to the correct spark plug. A few degrees play would not have any affect as the rotor arm would still be connecting to the correct HT lead?

J Smith

I can see you happily adjusting the points every 1,000 miles then checking the timing - but - what a dilemma if the 1,000 miles should happen mid-journey, do you stop and risk the wroth of your beater half?

(why would you change a condenser if its working)

you must try to get out of your Morris Minor habits, lots of tinkering and the odd bimble out, you've got a Spridget now, time tinkering is driving time lost and you should be driving the Spridget in a way that will lower your mpg, Spridgets are not for pottering about in

I think to get you in the right frame of mind we must part you from your flat caps and get those needles more easterly

if I was nearer to you I'd happily show you the way and the second I'd left you'd want to "just check" everything on the car and apologise to it for being pushed beyond what's considered polite

Nigel Atkins


If the rotor can move back and forth along with the cap doing the same....then the contact for making a spark will not be in the same place consistsntly

Prop and the Blackhole Midget


The rotor only needs to be vaguely 'pointing' at the correct HT lead. The cap and rotor can be moved relative to each other for many degrees, and it will not affect the ignition timing. The ignition timing is controlled by the relative rotational position between the contact breaker and the 4 lobed cam.

J Smith

getting very technical now (not), if the rotor is say slightly cw or ccw to where it should be and the cap slighly out in the opposite direction thus widening the gap between where the rotor sparks and where the cap posts are then wouldn't this perhaps cause problems?
Nigel Atkins

Thats my thinking nigal

After the timming is locked down and then the rotor moves retard and the cap holds its would be the same as adjusting the dissy retard id think because the rotor has a new contact postion in retarded then when it was orginally adjusted at.

Yes it appears minimal... but adjusting the dissy slightly can be several degrees....the smaller the diameter of the dissy head, the less it has to be twisted to make bigger degree changes.

At least thts how I see am I wrong?

Prop and the Blackhole Midget

But... if you can retard the dissy cap the same amount of degrees as you advance the rotor bug....then you would have same timing as if the dissy cap and rotor had never moved

Correct ??

(Please let me know if im being aggressive, mean spirited, and racist on this debate... ld hate to spawn another 115 comments on rude texting and forum decorum ....hahaha)

Prop and the Blackhole Midget

Prop; Nigel,

An interesting discussion :)

This is my (very rough) maths on it:

It is generally agreed that a spark travels at 3600 miles per second (very approx to keep the math simple). An engine revving at 6000 rpm will rotate 100 times a second, during which it will have rotated 36000 degrees. Therefore it will need a spark gap of 3600/36000 miles or 1/10 mile to cause a 1 degree timing delay - a gap of 176 feet!

Also the rotor arm is designed with a 'segment' shaped electrode, to allow for several degrees of rotation and still connect to the correct HT lead, so the HT gap will not significantly change over many degrees of rotation anyway.

This is all very ball park figures, but I still believe that a loose rotor arm or dissy cap cannot significantly alter the ignition timing.

J Smith

Jim is absolutely right.
The confusion arises because of the design of the dizzy that combines two quite distinct functions into one unit. The first function is of course the ignition timing which is achieved at the low tension side of the circuit to the coil. This is managed by the 4 lobed cam and the contact breakers. The second and separate function is the mechanism for distributing the high tension spark to the right cylinder, and in the correct order. This could be achieved perfectly well via a different component, and on early car designs this was the way it was done. The mechanism for this distributing stage was, for neatness and convenience, later grafted onto the top of the spark timing mechanism.

The only element of "timing" involved with the rotor arm is that the crescent shaped blade must be long enough to allow the spark when generated to leap to the right HT lead post as the blade passes by. But even then the spark will jump for only a fraction of the length of the blade
Guy Weller

I was thinking more of getting a fat spark to the right place more than timing but thinking about the width of the rotor arm end plate and dissy cap post combined gives a large allowance for the spark making it to the post even allowing for twist on the rotor arm and cap

I wonder if a loosely fitted rotor arm might push this allowance to give a more uneven receipt of the spark
Nigel Atkins

Couldn't think how to describe it but Guy and Jim are absolutely correct. The arm is simply a distributer, that is it points to a contact long enough to allow the spark when generated by the contact system to jump to the correct lead. If there is a problem with the arm it is either that it cannot conduct the spark (its shorted or corroded or the gap between the arm and cap contacts is too big) or its pointing at the wrong contact when the spark is generated.

The end of the arm is long enough to allow changes in timing of the spark such as happens at different engine speeds. If there is a bit of play in the arm or cap it is very unlikely to make a difference to the distribution.
Dave Squire 1500

Just an addition - I think most modern cars use individual coil packs for each cylinder. So both the timing and the distribution of the spark is done at the low tension side of things. The correctly timed and correctly sequenced impulse is then sent to the relevant coil pack to be amplified for that cylinder.
Guy Weller

all I can say is that altering the relative positions of the cap and rotor has brought the tickover back to how it used to be. And now I have a new project to play with - one that'll keep me grounded until it's fixed - the clutch cylinder!
Playtime coming up again boys and girls
Dominic Excell infected with confusion, I can not wrap my mind around this

Considering who the people are on the otherside of this debate, im going to have to give this alot of thought to comprehind the idea

So the postion of your debate is

that if the cap is devided into 4 sections 90, 180, 270 and 360, then the 4 electrode post of the cap are postioned at 45, 135, 225, and 315.....aka giving 45 degrees of advance and 45 degrees of retard for each side of the 4 cap elecrode post (fore and aft)

From 0 to 90 and 45 being where the cap electrod post is located does NOT matter where the rotor makes contact at on the post of the cap as long as its consistant ????

Are the interlocking fingers on the dissy body and the cap, there just to hold it into place NOT to be used as a dedicated postion of the cap as it relates to the rotor ??

Im pretty sure thats not what your saying, but.... (grasping)

Prop and the Blackhole Midget

OMG....I just had a brain fart epphime.

The 4 post eletrodes in the cap are NOT at 45, 135, 225, and 315 giving a spark of 45 degrees on ither side of the post

Because the spark will always occure "advanced" of the electrode post, never retarded....the only question is is how much of a gap the eletrical fire explodes before the the rotor makes contact with the elctode

OMG... the rotor never does make actual physical contact with the electroid post of the cap, does it ?

Brain in melt down mode

Prop and the Blackhole Midget

Right, now concentrate carefully Prop its quite simple really.
Applying Einstein's general theory of relativity and the first law of thermodynamics shows that the relative angular displacement of the rotor arm with respect to the distributer cap post is inversly proportional to the number you first thought of.
In other words - the spark plug only fires when the points open and providing the rotor and post are within spitting distance of each other - you're good to go!
M J Chapman

Back to the coolant showing just below the front left side of the engine block, pooling just below the cylinder head joint - I looked this evening to size up the clutch cylinder replacement job - and sure enough there was more coolant showing. A drip about the size of a pea had collected within 2 hours. Cold engine, not run since yesterday evening. I did tighten the clamps for the bypass hose (a good solid rubber one in good nick) It seems to show on the painted side of the block, running down about 1 - 2" back from the front face. Very clean coolant, not stuff that had been sitting around on the outside attracting dirt.
I'll be removing the manifold shortly to replace a blowing gasket, so hopefully can see better where the source of this leak is. I guess it is possible that while compression is good on all 4 cylinders, the gasket has failed where the waterway is?
Please can anyone tell me just which of the myriad of holes on a picture of a cylinder head is the water way? Looking at the front (UK) passenger side of the engine. To recap, no mayonnaise at all, no oil in the water. Compression all 150lbs across all cylinders on a cold engine. Just this constant seeping leak.
Dominic Excell

have you checked the thermostat area?

I'd dry the engine and dry and clean any suspected possible areas of leak and wrap dry toilet roll around them as any leak soon shows up on it

or (Guy, I think) has a method like using talc (but not talc) to track the origin of the leak and where it runs to
Nigel Atkins

Hi Nigel, yes, thermostat area is as dry as the Sahara desert on a drier than usual day. (I fitted a new gasket when replacing hoses a while back) When I get the manifold off I'll be in a position to give a much closer inspection to it all. Toilet roll is a good idea, I have some used hanging on the line to dry right now - just perfect for a job like this.
I may well resort to a leak blocker -I read somewhere recently that Leyland cars used it right from the start in all new cars. I should have made notes..... thank goodness for google!
Dominic Excell

"Please can anyone tell me just which of the myriad of holes on a picture of a cylinder head is the water way?".

Dominic. Coolant holes marked.

Lawrence Slater

That's great, thanks so much Lawrence, much appreciated
Dominic Excell

Full marks to Nigel
<<the exhaust manifold gasket when it start to go or goes can be noisy, sounds like something a lot more serious, from a flapping bit of metal to something very noisy in the engine - could also be something on manifold too>>
Manifold gasket was leaking slightly, this would explain some of the "fun" had while trying to balance the carbs. Main cause of noise was the manifold to exhaust pipe, very loose when the exhaust manifold was unbolted from the head, quite a gap there.

And even more marks here -
<<these are drips that remain on the engine so it suggests a leak that continues after the engine cools - the only thing I can think of for the drips there is the coolant coming out of the connection from the heater and running down the metal heater pipe to drip off nearer the front of it>>
The pipe was not accessible while manifolds were in place. The hose clip to this metal pipe felt tight, but was in fact just seized. Tightened up, and 3 hours later the engine is still dry as a bone.

Thanks all of you for your help - once the clutch cylinder has been sorted, it'll be back on the road before new year.

If I don't get on here before, have a great Christmas one and all!
Dominic Excell

Ahhh.... the heater matrix was leaking

Well thats doable, the good news is it can be by passed

Prop and the Blackhole Midget

Not the heater matrix Prop, the hose from the heater where it joins the metal pipe that goes above the manifold.
Just discovered another leak after leaving it overnight - front of the engine. seeping behind the front plate - see pic attached.
Very tempted to just live with it, and get some of that coolant sealant stuff.

Dominic Excell

On the plus side, it's definitely not the head gasket!
Dominic Excell

So it wasn't the taboo that no-one dared mention then. That's good!

Happy Christmas!
Guy Weller

I've had many, many problems with cars it's just difficult for me to remember them, or the cause, or the remedy

don't know if it's true but I do remember being told years ago that Cosworth (a Northampton company) put Barrs Leak in their engines (as much for conditioning I'd guess)

btw, there's a John Twist that shows how to check the tightness of clips :)

check manifold face is flat
Nigel Atkins


That leak in the photo is a hope is its a water pump going bad, if its not.... new block maybe be needed

Any chance you replaced hoses recently...last 500 miles, I often find I need to retighten new hoses after 300 miles as they tend to loosen for some reason...after that there fine

Prop and the Blackhole Midget

It's not the water-pump side of the front plate Prop, seepage from the front of the block / rear of front plate. Just bought some K-Seal so that should sort it once & for all. Allegedly better than Barrs sealant. Hoses have all been re-tightened, no leaks there. Water pump is bone dry.
Guy, it's not the FWB's so don't worry there! :-)
Nigel, I've just carefully scraped the surface of the manifold seating area, no bits of old gasket left. An old Record 09 1/2 plane blade works beautifully.
The clutch slave cylinder arrived today from MGBhive - ordered Saturday. Very fast delivery. I've been banned from the garage tomorrow though....

So, Merry Christmas to you one and all! And thanks for all the help and advice over the last year.
Dominic Excell


Just so im clear...

Your leaking water at.the front of the engine between the block and the front engine plate on the carb side of the block ....and the water is not comming from any other source ??? Just that location ???

The water pump is dry, the hoses are all tight, nothing liquid got accidently spilled on that location

Dom.... friend buddy brother...there is a water jack at that location on the block, but if its sprung a leak at that place.... its not fixable that im aware of

I think bars or anything else is going to just be a minor temp fix.

At this point, id enlist the advice of a professional

Ive never heard of a block craking at this spot, normally the block is drilled for 11 studs and someone over thightens the new front stud location and cracks the water jacket at the topp of the block but that dosnt mean much

Im so sorry dom, have a good holiday and hope for the best
Prop and the Blackhole Midget

There you are! That is the taboo that no-one should mention that I was referring to! Now Prop has gone and done it. Tempting fate, I would say.

I have always added a dose of Barrs or similar on any engine after a rebuild, or after a major refill of the cooling system. Just as a matter of course; something I started doing half a century ago, and still do.
Guy Weller

That sounds very nasty Prop and Guy. Never come across that problem I have to say, but I sincerely hope I haven't now. The water loss is very slight, so will see what happens. I'm hoping it is merely sloppy tightening of the nuts and bolts, as there has been evidence of this on other parts of the car. Could just be not bedded down properly or re-torqued. For instance the cylinder head was only torqued to about 25lbs on some of the larger nuts. (Now sorted of course!)
The engine was completely rebuilt about 9000 miles ago (I've done 6000 myself) - reground crank and bores, new pistons etc. I'd hope they wouldn't have gone to that trouble on a knackered block....
Dominic Excell

Is it still 9 stud or is it converted to 11

Gez, I really didnt want to say anything like it....I have to say dom, youve been all over this thread like a child at a roller coaster theme park

Im really having a hard time thinking its a craked block esp in that so beefy,

At this point ... because we are chasing water leaks.... if it were me personally id be adding lots of food coloring to the water , modify a rad cap to hold an air chuck and hook up a compressor to prssurize the system with around 20psi and start....go to lunc for an hour and then start looking for leaks...maybe even spray aroud the joints with some dish soap mixture and look for bubbles

Im not sure thats a good idea, but its an idea that if works would give you some direction to go....whats the bbs opinion ?

Prop and the Blackhole Midget

I wasn't mentioning the "taboo" because I would think it highly unlikely, or extremely unlucky if that was the case. Much more sensible to presume something simple and straightforward and just to work methodically through the checking and tightening sequence.

"the cylinder head was only torqued to about 25lbs on some of the larger nuts" I wonder, did they use the proper hardened flat washers, or just standard bright and shiny mild steel ones? They will deform, gradually reducing the tension (torque setting) on the head stud nuts.
Guy Weller

Sorry correction.... I said pressurise the system ( then start)

Do not (then start)... that was a typo, please delete (then start)

Prop and the Blackhole Midget

Big ( X 2) guy....

I had that same thought when mentioned that,

also look to see if there split washers, also a no no

They need to be grade 8

Also look to see if the studs are finger fight or are they torqued tight into the deck of the block...they need to be only finger snug tight as the nuts do the clamping .... not the studs

Might try dipping studs and nuts into motor oil to provide better clamping of the threads

Prop and the Blackhole Midget

well the rocker cover is back in place and I'd be risking life and limb to go out playing with it now (not really, my better half is brilliant!)
I didn't actually notice the washers, or how tight the studs were, as I didn't undo, just backed off about 30 degrees then tightened to torque. (9 stud Prop) I didn't want to risk buggering up the head gasket on case it was ok.
If there is still a leak after adding the K-Seal - I'll live with it as it would take about a month of hard driving to make it drop noticeably.
Dominic Excell

I hate to keep beating this rain deer with a red light for a nose

But im still thinking condenstion....these engines put off alot of water when they get frozen cold for a day or 2 then a nice sunny warm day or a great santa wood fire place heating the garage Garage. A pint of water run off would NOT make me gasp in the right conditions

Prop and the Blackhole Midget

Deffo not condensation - clear blue tinge to the water which tastes of glycol
Dominic Excell

OK, the leak is definitely not from between block and front plate - possibly from the water pump gasket, but more likely from the top joint of the bypass hose.
I was given a head-torch for christmas, and looking this afternoon I saw a drip suddenly descend from the front face of the head, in line with the bypass hose. I then found that the (difficult to get to) clamp to that hose wasn't in fact all that tight - here's hoping!
I have some K-seal in hand if that fails!
Hope you all had a good Christmas! I did!
Dominic Excell


When you get yours fixed, come fix mine...hahaha

I hope that solves it....but if its that "accordion" hose, keeps leaking after its tightened up, that thing is thin walled, it can be cut from over tightening

2nd thing id look at is a water pump going bad, cause they will leak also and hard to see it

Congrats on the flash light ... I got a raindeer that craps chocolate covered rasins out its back end...

Im not sure what that means....hahaha


Prop and the Blackhole Midget

None of those accordion types in my garage Prop, they are truly sh*te, probably came out of the same reindeer's ar*e that your chocolate raisins came from!
Talking of which - the girls were watching a film called hairspray, and as I came into the room, a shopkeeper was showing off a novelty cigarette dispenser - a donkey. You lifted the tail and a cigarette popped out of it's ar*e. I'd have loved to have found one of those for my dad before he went! He smoked those nasty little cheroots that would have been more realistically coloured.....
Dominic Excell

I dont smoke, but even id like I dont know, but ive never seen the film hair spray.

Id say you whittling the issue down, its getting there...keep at it, the more no's you find the closer your are to "bingo"

Hang in there

Prop and the Blackhole Midget


IF it's still leaks after this from the bypass then I would wonder if -
a) the clamp(s) are faulty
b) it's the hose that is actually leaking
c) the metal connecting tube has corroded so that when you tighten the clamp it deforms

pity that toilet paper didn't dry out on the washing line ;)

you don't seem to have been allowed to give your full attention to this matter, what with your previous comments we'll be monitoring the situation, we've seen the recent TV ads ;)
Nigel Atkins

I know Nigel, firstly I wasn't allowed in the garage on Weds - turned out it was Christmas day so my presence was required - something to do with stuffing turkeys I think. Then this damn wind blew the bog paper away.
Dominic Excell

>>Then this damn wind blew the bog paper away.<<
yes that would leave you in somewhat of a mess but you're causing me more concern by being confined to your house, if this continues we may have to work out a code word for you to let us know it's all gone too far, heed the words of the Hollyoak stars
Nigel Atkins

""Then this damn wind blew the bog paper away.""

Thats why in missouri in our out houses we use the pages of the sears catologs and corn cobs for those moments when we fill the need to be extra clean

Prop and the Blackhole Midget

Speaking of head gaskets. Does anyone know what Sussex car parts supply in their kit GEG1140 for 9.77 plus postage? Can this be a Payen for that price? I'll ring them when they open again on jan 2nd, but I'm itching to know now. lol.
Lawrence Slater

I wouldn't have thought it'd be a Payen at that price Lawrence. Do let us know when you've found out! We're all now itching to know too!

Just checked the engine again - ran it up to temperature - looks as if my efforts have paid off at last!

Now to sort the replacement clutch slave cylinder.
Dominic Excell


If I a complete gasket set for under a tenner....I dont even bother to take a breath to ask how bad it even is

The head gasket imnsure is not much more then a thicknsheet of aluminum foil sprayed with copper seal, and black spray paint

I cant even imagine how bad that kit even is

Prop and the Blackhole Midget

Not wanting to drift the other current HG thread("Head gasket supplier"), and as I've already posted in this before, I'll update this one.

I bought the cheap HG set below, from Sussex. I used it to replace the HG on my '73 1275 Midget. It seems fine and good quality. The only problem I found was that the first one they supplied had holes stamped a little out of alignment. They supplied a 2nd HG kit on request FOC, and the holes aligned perfectly.

So far, all I've done is install, torque, run to temp and torque again. I checked it last week, and it didn't need torquing. I've no idea who makes them, but at 9.77 plus postage, for a HG, rocker cover cork seal, and an exhaust manifold gasket (works well too), you can't lose much and the chances are you won't lose anything.

So whilst payen I agree are very good, these might not be a bad and cheaper bet either.

I'll update this if it fails, or if after another year, it hasn't.
Lawrence Slater

Remote clutch bleed.

Alan Anstead

Yepp... always bleed the clutch before replacing the head gasket Or you will be sorry.

Prop and the Blackhole Midget

This thread was discussed between 18/12/2013 and 31/08/2014

MG Midget and Sprite Technical index

This thread is from the archive. The Live MG Midget and Sprite Technical BBS is active now.