4 head gasket failures later and we turn to you for HELP!

We’ll hope you all had a great bank holiday weekend, we are back again to tackle the Mercedes engine and also ask for your help on this Morris 12 4 with constant head gasket failures

[@johnlawrence9066]

Used to get this problem a lot with the side valve Standard engines . In these cases , the top face of block , especially after lots of skimming , becomes thin . As you torque the fixings , the block face is pulled up around the stud and the gasket doesn't have the same pressure all over . Over tightening the stud in the block can create the same scenario . Managed to recover some blocks by machining the stud holes out in the block to find thicker wall , and making threaded inserts , and fit / seal flush with the deck . Regarding gaskets , use the thicker composite version , and stick rigidly to the manufacturers torque settings . Just sorted successfully a 1933 BSA engine suffering from the same problem .

[@felderup]

so, sanding on a surface plate or glass sheet might show the humps?

[@mfree80286]

@@felderup Only if they deform enough to take a set. If I had to prove it I'd probably take a thin head gasket and paint it with something deformable that cures, dress the other side with silicone spray (mold release), install it, and let it set up. Removing it should leave the painted material in it's installed thickness, and as such any thin spots are where the block is drawing up and thick spots are where it's too thin to maintain holding pressure.

[@felderup]

@@mfree80286 dyechem or prussian blue would be the classic method.

[@kenmcnaughton5882]

I used to work in a garage many years ago in the 50s, when there were lots of the old Morris cars about. i seem to remember fitting the three part gaskets, you know two copper pieces with asbestos in between .

[@DARANGULAFILM]

The old Payen copper-asbestos-copper gaskets used to have a folded rim around the chambers and water ports. If the old gaskets can no longer be found, my personal preference would be to rim the chambers and water ports with very thin soft copper shim material or even alfoil. It will be a PITA to cut. Some of the older castiron was pretty soft stuff. It was not uncommon for Austin 7 and Austin 8 head studs to pull their threads along with a surface crater out of the block. You might get away with painting borders around the chambers on the head and the block with material which has metal bulking substance in it like cold-galvanising paint or old fashioned silver-frost paint if either can still be found. A modern equivalent might be metallised automotive lacquer. The borders around the water ports and the chambers might be masked off to leave a rim of about 5mm broad and the material applied with a spraygun. It was a rule of thumb back in the days of no money to buy a new gasket to re-use the old one and give it a good coat of silver-frost. In the 1970s, folk used an old and very sticky material in small bottles to coat the gaskets. I have not seen that sluff in years either. I even saw honey and golden syrup used. The surfaces must be absolutely clean of anything oily or the honey will bead off. Another personal preference would be to set all tensions lower than present day modern bolt/stud materials specify and tension the centre row of fasteners lower. It seems apparent that centre row fastener tension is either pulling the block high between the cylinders or pulling the head down between the chambers or both and reducing clamping pressure where the chamber pressure is going to be highest. Old-school very compliant gaskets probably took care of things. I doubt whether the block or head castwork will have the strength to compress an annealed solid copper gasket into compliance. The cast pillars will pull the head down firm in their areas of contact but allow the rest of the head to yield slightly and maybe even wedge off where the blowtrough is happening. My vague childhood recall is that backyarders often re-tensioned their head bolts three times or more over the first 1000 miles with the first done after the first start with the engine warm and subsequent re-tensions also done when the engine was warm. Hopefully I am not sending you down a rabbit hole with this comment. Try enquiring with New Zealanders. Due to import bans, they recycled older models far beyond their normal use-by date to the point of even re-metalling bearing shells. A good start might be with the folk who are scratch-building Gnome-Rhone WW1 aircraft engines and rebuilding RR Merlin engines.------- cams.net.nz/about/ --------

[@felderup]

sounds like the old trick of using hemp thread as pipe thread sealant, old tricks, for the era, might be exactly what fixes things. a little sugar water would make something like a carbon layer on the copper. i've seen some high tech engines with carbon fibre gaskets, with copper edges, that's gotta do something.

[@petergillett5198]

Many years ago I was told to put a slight countersink on the cylinder head stud holes to avoid problems with the stud raising a lip in the block

[@CrimeVid]

I've heard of that before,can not remember in what context.

[@RotacRepair]

I make my own copper gaskets for antique aircraft engines. I would anneal the gasket yourself. Starting with a clean gasket, mark the complete surface with black Sharpie marker lines and heat the entire gasket until the sharpie marks disappear. Then let the gasket cool at room temperature. Do not bend or flex the now annealed gasket to confirm its soft. Next spray both sides of the gasket with "Permatex Copper Spray -A-Gasket" as per instructions on container. Assemble with normal torque procedure. Lastly retorque after first engine warm up.

[@ericd7532]

Don't "retorque" torque to yield stretch bolts that most modern engines use

[@RotacRepair]

@@ericd7532 absolutely true! However I don’t believe that old flat head would use stretchy bolts.

[@SportsRacer-du6ms]

when re torque back the nut off then re torque do individually and do it after 1 heat cycle

[@bluemule3891]

Hey Lee, I concur with Rotac, and along with everything else they said, for emphasis the second torque after first warmup is essential for good sealing. Annnnd the pro tip of the day, get a "go no go" feeler gauge, it takes the "feel" out of feeler gauge, faster and more accurate.

[@brianb7636]

I would coat that gasket with Wellseal (thinned if necessary). Always worked for me on single layer metal gaskets. Old school product but so is that head.

[@danpascoe2139]

Check the dowel pins i had a customer that had same issue on a 103 engine head and block had been surfaced not allowing head to seat due to dowel pins being to tall

[@simondrake8909]

How about either a thicker washer or an extra washer under the head nuts, in case the threads on the studs are not long enough???

[@VinceT2940]

I think your answer is the most likely cause of the problem, the studs might very well be slightly too long and bottoming out in the block!

[@lesprudence374]

I thought exactly the same thing.

[@michaelmason5459]

Had similar problem on 10hp prefect block head and piston been skimmed, it had a thinner 8hp pop head that had been skimmed which caused nut to lock out on studs threads before full pressure on gasket. Old cars get altered over years of use.

[@barbaraneville5036]

Sounds feasible after all Lee said he couldn't find a dimension on the standard size a head thickness would be or maybe just run a die down the studs but the washers are a simpler idea . Also the increase from 6.2 to 7.4 compression ratio could tend to stretch the head studs if they are old when the engine is given some beans

[@leesmith1558]

I thought that, are the nuts bottoming out on the threads somehow?

[@bobmizen1]

Very interesting problems to solve. Did you get a mysterious package of AA batteries for your clock? 😂 just thought I'd give some humour back for all the entertainment you provide. Best wishes, Bob M. South Wales

[@dougjoseph8094]

When you use copper or copper laminate gaskets we always lightly greased both sides of the gasket to allow them to spread as you torque bolts, always stage torque with at least three increasing settings. Run the engine no load(don't drive) cool overnight then in sequence loosen each bolt 1/4 turn then re-torque. Don't assume bolts are correct and free running check all bolts easily screw home and don't bottom out, lubricate thread and bolt head face. These days with stretch bolts nobody needs to retorque, in the past we had to allow for stretch and shrinkage, some manufacturers even recommended a further retorque after 500 miles I enjoy the show but wonder why you always hone pistons to push fit gudgeon pins we always used hot water to expand piston after all they will expand in use

[@derekmcfadyen127]

Had the same problem on a k series years ago .....in my case it was the dowels on the block sitting a shade too high .........

[@jizwinkle9822]

I would use Hylamar Blue on the head gasket. I use a very thin smear on all steel head gaskets. Especially the ones that they say to use nothing on. Also, an odd reason for overheating and blowing gaskets is, the water pump sucking the rubber coolant hose closed when your revving these older engines more than normal. Many of the older cars had a steel coil in the lower hose. I finally diagnosed a over heating boat engine, luckily seeing the hose collapse as the owner revved it hard against the pier.

[@jan-akebarme4314]

Hi guys, I would very much like to see the studs and nuts on the engine block for that head. Many of those old side valve engines used UNF or other fine thread Imperial studs and nuts, and these are very, very, very prone to have huge friction if they aren´t very thoroughly wire wheeled, and / or cleaned up with thread cut and tap respectively. Furthermore they need to be lubricated with 20/50 motor oil or similar before being torqued. I have seen experiments where very knowledgeable people indeed have calculated and measured the proportions between friction in the threads and actual clamping force in tons ( newtons / pounds ) down towards the head gasket. With rusty, sooty, corroded threads it is possible to lose 75% of the clamping force down towards the head gasket !!!! Even if that most likely was a quite extreme case it may still be possible to to lose half, or one third of the actual clamping force to friction in the threads. Without knowing most of the background facts I of course cannot know if thread friction is the actual culprit in this particular case, but, I do want to mention the possibility, just in case it perhaps might have something to do with this. VBR Jan-Åke Barmé

[@jiminycricket9877]

Are the studs pulling out of the block? Put a big chamfer on the stud holes. Also check the nuts aren’t bottoming on the threads. I’ve never liked solid copper gaskets with no fire ring. Good luck!

[@gregculverwell]

Not possibly running out thread on the studs?

[@richardjackson5380]

This

[@ukmechanic8923]

Lee, you might want to check that the head nuts are not hitting the end of the threads on the head studs before fully clamping the head down, especially with both the head and block refaced? I had a similar issue on a 1939 Bentley Derby, solved it with thick washers under the nuts.

[@woodpeckerdrums6254]

Happy easter ...big smiles

[@chrishull4174]

Hi Leigh my immediate thoughts on the head gasket situation were a simple one . I noticed others have mentioned already. I've had this happen with me myself, has the customer fitted washer's under the headbolts / nuts. They may have been mislaid , bolts are binding on the head giving a false torque down .

[@mikehipperson]

Back in the day, my first car was an E93A Ford Prefect with a side valve engine. The head gasket blew after my very first trip to Brands Hatch so I got a new copper one and it took about half an hour to replace. The trick the gasket supplier said was to liberally coat both sides of it with axle grease. It seems it takes out all the possible imperfections and 'welds' the head and block together!

[@dingodoctor7373]

I have built a lot of old engines in my 57 years of work and not had a problem like this. Personally, I would avoid solid gaskets if possible, the original would have been Copper/asbestos laminated, which clamp down and seal much better. A few thoughts, the solid gasket has to be annealed, heat to cherry red and quench, then it is very malleable and will clamp down better. Due to the age of the car, the head may have been off a lot of times as decoking and lapping in valves was a frequent task in those days, so the head could have been skimmed a number of times, might be worth the owner contacting the Morris owners club to see if the they have a measurement for the original height of the head. My personal preference for a gasket sealer is Wellseal (Heldite is not as good as Wellseal). Lastly it might be better to source a copper and substitute asbestos gasket. Try Cox & Turner from near Yeovil, they are engine recondioning specialist for older engines and have a large stock of parts.

[@darrelljones8218]

Yes to anneal copper,, Cheryl red and quench in cold water.

[@adrianrigby1933]

If i remember right, it s a long time ago. Copper asbestos gasket with grease on the copper face usually worked fine. As with all old engine /cars people are now seeing problems never seen when the cars were current ,younger.

[@fpreston9527]

I once had an astra van blowing head gaskets. It turned out to be years of debris had compacted down the stud holes in the block . I ran down each hole with a tap and air line. Job sorted ._ The head studs were bottoming on the shite .

[@dodgydruid]

I would look to any possibility of a collapsed barrier between oil and waterways, would also recommend looking at the waterways in general as a silted up engine like the Austin 7 will blow and blow gaskets until you remove the chalky deposits usually accrued at the furthest point of the circuit from the radiator. Reliant with the OHV engines actually put in a bolted port right at the back of the cylinder head to allow folks to bleed out air locks and also probe out the collected silt and detritus.

[@leechamberlain5706]

I agree with Rotacrepair i have always done that process with our vintage tractors.

[@hiltonmccowage9436]

Simple solution. I have vintage diesel engines. No problems with copper gaskets. Use copper coat as per instructions on all surfaces. If done correctly it will seal for life.

[@user-rb2ek7qp1m]

Don’t forget to install the tensioner before you remove any cam chain links’s

[@chrishoughton2228]

I'm not sure i would want to use heldite or any other gasket jointing compound on an annealed copper head gasket in that application. Considering the area which is being clamped by those bolts on that side I suspect that the clamping force is being used against the jointing compound and not the copper itself. I'd also have a good think about the torque sequence. It may have been done in the specified way but does that way make sense?

[@bish1121]

Back in the 80s i would heat up copper exhaust gaskets on a Primus stove till they glowed cherry red & puffed up. If done right it should expand & be soft. but by looking at the head gasket it doesn't even have any witness marks where i would of thought it would have puffed up bits & squashed bits. Measure it Get the blowtorch out heat it up & see if it expands 👍.

[@ferrumignis]

How would a solid bit of copper "puff up" when heated?

[@bish1121]

@@ferrumignis copper when heated resumes it's former size as in when it's squashed then heated very hot! It will grow in size back to near enough what it was. Twist a spring out of shape then heat it & it will become a spring again. Don't quote me as I'm not a scientist 😁👍.

[@ferrumignis]

@@bish1121 Heating copper anneals it (makes it softer) but it doesn't have any shape memory. This is why you can only reuse copper gaskets and washers a limited number of times, they get thinner at each reuse.

[@ClassicMiniMotoring]

Nice to follow the A-series to get build.

[@matoroberts]

You might well do this, so forgive me if you do. But in the performance diesel world, when there is going to be high cylinder pressures, we build the engine up, then run hot water through it which allows the metals to normalise before there is cylinder pressures (so its settled using heat without cylinder pressures).. re torque the head bolts / studs - normally find they are 20nm less than they were first torqued then we never get head lift. I thought most people would do this with performance engines. Just use a tea urn or kettle and a pump. To prove my point, next time an engine is built, check the head stud torque after its been run up, bet its less that the correct value. 👍

[@G-ra-ha-m]

I had this with a Triumph 1500, checked the head bolt torque after a week and they were almost loose! Engine never gave a problem though 😊

[@frogandspanner]

1:40 By the time you have made all the mistakes you are an expert.

[@davidbillington9654]

The Mercedes engine adjuster may use a self locking thread like Ford used on the Xflow rocker arm adjusters. IIRC there's some information in Machinery's Handbook about Dardelet thread which does that.

[@Sandysand701]

The torque wrench he used might need calibrating

[@Mercmad]

Ever been asked to do a Mercedes 190 Cosworth engine? With the tappets on the M110,the tappet clearance is right when it's hard to draw the feeler guage out . The ball studs are checked with a torque wrench to make sure the threads aren't worn out and causing the tappet clearance to open up. They are a rattly engine normally but loose tappets make them really noisy. The threads are pretty special being dual pitch thread form .A mate of mine had some made and it took weeks for the machinist to figure out how they were made .They were for a M100 6.3 liter.

[@TheMadManPlace]

I don't think a young chap like yourself would ever have seen the Ford V4 motor. If ever there was a complete disaster of a motor that came out of Ford, THAT WAS IT. It got so bad in my country that the agents would take those lumps out of unsold cars and replace them with 1600 Kent motors just to get them sold. Those things didn't even need a reason or excuse to blow their head gaskets - they just went ahead and did it. We tried EVERYTHING and then some to get them sorted out but NOTHING WORKED (I lie - one thing did work but that led to another issue - tell you later...) We even went so far as to machine out a small "combustion chamber" into the head - they had the combustion chamber in the piston and a "flat head" like the standard Kent motor. As to the "lie"... We used to do A LOT of marine trawler motor heads and one of the ships engineer guys gave us a piece of marine steam packing to use - a lot of graphite in the material and thousands of fine steel wires cis-crossing, embedded in the material. So we cut out 2 gaskets (V4 remember). Then he told us to soak them in Jeys Fluid (an old school cleaning agent - probably not too safe for today's people) over night and install them the next morning. Evidently as soon as some heat is applied, the graphite and whatever else was in the material combined with the Jeys fluid chemically welded the gasket to the cast iron of the head and block. WORKED LIKE A CHARM... The problem came at the first service - the mechanic at the service center dropped a nut down the carb - didn't notice and turned the motor and one of the cylinders ate the nut. So now we have to lift the head to see what the damage was... THERE WAS NO WAY THAT HEAD WOULD COME OFF !!! We even ran the motors with ALL the head bolts removed - it just stayed stuck. Eventually the service center sent us a replacement Kent motor to put in. Us apprentices decided that we were going to get those heads off somehow so we took the crank out, broke up the pistons from the bottom and and removed the rods and pieces, put a 2 inch rod through the bore and using sledge hammers, tried to beat the heads off. We did NOT succeed...

[@leecunningham5062]

Look for torque to yield studs to ensure proper clamping. Retorque straight after warming up. Road test with a thermal gun to look for localized over heating / poor circulation Probably doesn't have a water pump, check for plugged cores in radiator, thermo syphon system needs good flow to work

[@richwaikato73]

can confirm what @RotacRepair has said. The only thing i would add , research the gasket with an old timer parts guy. Some of the older engines that ran copper gaskets, had options for different thickness. Not sure on this model

[@kurtweir2256]

My brother had an issue with a 1928 Caterpillar model 15. It was fine until you made it work. The head had been cut and corrosion inside the head left the head too thin to be stiff enough and it would flex. He cut sections out and brazed in patches. It was complex but successful.

[@iainball2023]

A distinct possibility 👌

[@lelandlewis7207]

The issue seems to be on the piston side of the block, which is the weakest due to the water jackets and would have the most stresses due to the crank being on that side, possibly unseating the gasket. Is it possible that you have a thin deck allowing distortion under the load of the studs being torqued? Maybe make some sort of a torque plate setup that would allow measuring the deck after torquing. A possible patch would be to anneal most of the gasket, leaving the area between the bolts on that side harder, which would allow less squish and create almost like the Fel-pro Permatorque, which is thicker in certain areas to even torque pressure. Or maybe the opposite, anneal that part more so it is more malleable. Since it is just a guess, I'm not sure which, or if either would work. lol Maybe a thicker gasket that can take more distortion.

[@nigeldlm]

I had a similar problem on a mini to yes ago lol the head and block were flat but one was on an angle by a small amount and it allowed blow by once the heated up !

[@PatGill-tu6oq]

With my vintage SV motorcycles I have to tighten them down three or four times after running them for the first time, 1st after running for 5 mins, 2nd after a mile or three third after say 10-15 miles and fourth after say 50 miles,

[@raysilver2445]

It looks like others have beaten me to it on the side valve engine the head nuts not actually pulling the head down, I used to help my dad do headgaskets in the fifties and my job was to soak the copper and asbestos gaskets in warm water to make it swell then when tightened down it takes up any undulations if it has to be a solid copper then it needs to be properly annealed.

[@bobawatsit]

lots of good reasons for problems suggested by others, ......... but cutting out large chunks of copper gasket, increases clamping force

[@keithlockyer4215]

Try coating gasket with Heldite had great success with this product from 1960,s onwards and still used at company I retired from 2 years ago

[@davidgerrard8661]

Grace engines just done an A series Lee. Incredible work well worth a look on their channel

[@frogandspanner]

5:34 I really like the Socratic dialogue approach. A pal and I were discussing an interactive exhibit at the Royal Museum of Scotland in Edinburgh, discussing what scientific principles it might be demonstrating. About 5 minutes in we realised that about 20 people had gathered around us, listening intently to what we were saying. Slightly embarrassed we continued, and received a round of applause as we finished. It made me realise how powerful a pedagogic tool the intelligent question-answer technique was, and how engaging others found it. Develop it!

[@ouroborosirvington]

🥸 🌪 🕳

[@user-zm8km1kx6m]

Are you tightening against the threads of the studs? Not enough thread length ?? Saw something similar on a new cozy block which hadn't been machined deep enough for the head stud and blew oil and coolant out on start up. Sawed off 5mm off each stud it was fine....

[@michaellawrie496]

Like everyone says check dowels and studs for binding. All new solid copper gaskets need to be annealed properly by heating cherry red then quenching. Solid copper gaskets can be fitted with light greasing or ....painted with silverfrost paint and assembled wet. Compression shoudnt worry too much as this works on motorcycle engines with over 11 to 1 and also gaskets as thin as .015. Your engine sounds like binding studs may be the problem.

[@johnhewett2525]

Years ago, silver frost paint was the go, only paint the block side of the gasket as for some unknown reason I was taught that if you paint both sides the head is very hard to get back off. I don't know if this is true as I did as instructed and never had comebacks.

[@chrisblood7395]

I can't speak to that Morris engine specifically, but from what I remember about American side valve engines - or, flatheads, as we call them? 7 point something compression is, indeed, rather high. A thicker, multi-layer head gasket may, indeed, be the solution...

[@graham6760]

It sounds like lack of clamping pressure. If the gasket is annealed correctly and there is no mechanical problem you should see clamping /witness marks on the gasket. I couldn’t see any marks on the gasket but it was difficult to see

[@graemegill4773]

Head nats are bottoming out had this happen on a ford Cortina went through a few head gaskets before I worked it out

[@stevefuller1779]

The comments below are what I first thought but it is so obvious that I can't believe that the customer would not have checked already. I wondered if, being quite thin, that the head is flexing when tightened right up, I have had things like water flanges do this and actually stop leaking when I have loosened them a little, perhaps try tightening the head bolts a bit less and see what happens.

[@seriksson9721]

Grease on the threads of the cylinder head bolts could be a tip or oil in any case.

[@peterknight4692]

What were the other types of gasket? Did they all show the same pattern of failure? Is the pressure relief valve in the water system operating correctly? Is his torque wrench accurate?

[@juraphotos7489]

Just a idea I wonder if the head more probably the block is warping when its getting up to operating temp possibly caused by a hidden internal stress crack A shot in the dark might be worth a try warming the block and head up very slowly and evenly to operating temp and checking it with a true straight edge and feeler gauge or a DTI good luck. ps cool it down very slowly as well

[@mkllove]

Your suspicion of C.R. is a good start.. have you measured min max swept by pistons, vs remaining volume of cyl head to get calculated C.R. ? Since "it's never been right" as stated, were incorrect height pistons already installed, and you mentioned he checked bolts for tightness, but HOW did he do that ? Did he attempt to repeat original final torque spec, or just that they "felt tight", there can be a measurable difference. The only other probable cause is bolt length, or threads pulling vs nuts backing off ie relaxing clamping pressure... were studs re-used or new replacements ?

[@VintageSG]

There's nothing wrong with using two washers twixt nut and head. A dob of grease will ensure they slide over each other during tightening. Reduces binding. Anneal the daylights out of the gasket. Rough the surface with a scotchbrite and anneal again. Using narrow copper tape ( B&Q 'slug barrier' tape ) make a fire ring around the combustion chamber cutout. It's a gnats cunt-hair thick, but that's enough to really seal the chamber. The ends need to abut, not overlap. Copperslip or blue Hylomar to both gasket surfaces before reassembly. The gasket needs to be able to 'move' slightly during torqueing. At least three stage tightening. Fire it up and have a brew while it warms up. Don't drive it. Let it cool. Retorque. Drive it fairly gently for a few miles. Retorque. Retorque a few hundred miles later. Solid copper gaskets are OK, but they can be a pain in the backside. I did the above on my Mini after it blew the gasket first time and the vendor explained it to me as if he was teaching a village idiot to use cutlery. I've done it ever since when making gaskets, including with a 2.5DI Transit, and never had an issue. Perhaps it's voodoo. Maybe it's all bollocks and just annealing until the copper is pink and staged torque is the key.

[@gtxguy]

Fastener issue, check the lenght ,check for over tighten and stretch.That's where I would go first...good luck

[@rogerking7258]

Well, first I'd check head and block again for flatness with a certified straight edge. Then make certain that the nuts are not bottoming out on the head stud threads and stopping the head being clamped down properly (easily fixed with thicker washers). Sidevalve combustion chambers are nowhere near so efficient as modern 4-valve ones, but even so I doubt the 7.4:1 compression ratio is a problem since even E10 is way higher RON than the fuel available when the car was new. It would be worth checking the ignition timing and advance curve (so far as I can see there is no sign of detonation in the head, but the pistons are more easily damaged and I haven't seen them), not forgetting that if timing is significantly too retarded this will actually cause combustion chamber temp to increase. And do check the radiator, block and head to make sure the coolant can flow freely. Check that the water pump (I think this engine has one) works and finally, make sure that the coolant holes in the gasket match the head and the block. Other than that I personally would use the most modern tech head gasket available. If the engine shows _any_ evidence of overheating for whatever reason, I would strongly suggest that you pop the pistons out to check for scuffing on the skirts and 100% fit another set of rings because they can lose their temper and not seal to the bore face properly. Good luck, but 40 years of experience has taught me that even the most puzzling problems have a cause.....................one other thought - if the head studs are into open (i.e. not blind) threads in the block it would be a good idea to fit them with some hydraulic sealant so that water can't escape up the threads and out from the head/block joint.

[@kenwastlund3968]

Bottom of block is cracked above ctr main, ergo moves when warm. Odd not cracked into water jacket.

[@daledavies2334]

Flatties have a hard time with getting high compression ratios and thus cylinder pressures. They normally do not have head gasket problems unless supercharged. I find it curious that the gasket is showing it got hot on the cylinder side. Considering how quickly the gasket is passing combustion gas it can not be a lean mixture allowing the head and block to get hot on that side. I would be looking to the bolt clamp load. Was the head milled to raise compression and the head bolts or studs are a smidgin long? Do you have the block in the shop?

[@stuartmorris3407]

The gasket seems have a lot of surface area. I wonder if this is making it difficult to conform to the block and head decks. Thougher and uniform annealing might be the answer together with a coating of grease to allow the gasket to settle properly.

[@MrFunkia]

It maybe a problem with the block, although it's unlikely. Check it over for cracks etc

[@johnthompson1252]

Oldschool side valve engines need a fibrous head gasket ( replacement / substitute for asbestos gasket with copper plate either side ) sandwich type gasket ….. copper alone just blow out on the vintage lister petrol engines I used to restore

[@paulnolan1352]

Cheers Lee, if that’s a pure Copper Gasket with no laminate it will blow, it needs to stay compressed. Copper is too soft. If it is laminated then it sounds like the oil on top of the pistons is doubling the compression and blowing out the Gasket. Where is the oil coming from?.

[@hg60justice]

you said the head and block were decked. were they checked again before assembly? sure doesn't look like some area is getting clamped as hard as the rest. maybe the internal structure of the block is gone not allowing proper clamping from the studs? but i'd start with a straight edge and check the block and head first.

[@GeeenJ]

we had a similar issue 40 years ago in a workshop i was at we put the head on the block without a head gasket torqued it down then checked with a feeler gauge all round found it wasn't seating and the feeler gauge would go under in some areas it was the dowels too tall after the block was decked took a few thou off the dowels used hylomar sealant on the head gasket and problem solved

[@rgthomson1]

First thing i thought of was a problem with compression ratio, maybe need the pistons getting a bit of them on the lathe, someone maybe changed pistons or rods and maybe didnt measure up right

[@derekbevan7145]

Back in the dark ages folks racing ford sidevalve E93A engines had problems with blowing gasket,the problem was down to the area of gasket between the combustion chambers,the answer was to carve out areas of the gasket thus reducing the area and increasing the pressure exerted on the gasket, on the Ford it was the large area between the two centre cylinders.

[@phenogen8125]

I would concur with that concept but suggest parallel slot cuts or surface grooves to one or both sides of the gasket in selected areas to form an effective labyrinth seal as well as allow micro movement to non sealing gasket areas on periphery rather than complete cutout might prove superior. Labyrinth seals are used on high pressure turbine shafts very effectively. The references to texture of the prepared surfaces by others here is already recognizing the function of labyrinth sealing potential but not differential pressures and gasket movement.

[@user-rn3xv6vg7w]

My first thoughts mirrored @phenogen8125 idea with regards to large areas of the gasket being too large and therefore not achieving an even clamping load. The idea of an even thickness/width always matched what I wanted to achieve when making a gasket seal. So the labyrinth idea gets my thumbs up. I recall from years ago that it was always recommended to retorque after the engine had been thru a heat cycle. My other thought was to ask if you did a hardness test of the removed gasket just to confirm if parts had become harder than others whilst in service. Good luck there seem to be plenty of excellent offers from hardened experience in all the comments.

[@gta427]

Check the studs are square to the deck, we had a customer bring in a side valve Austin with continual head gasket issues, turned out who ever did some thread repair had probably drilled the holes by hand, we squared them up, problem solved.

[@philhermetic]

when annealing the head gasket it needs to be heated red hot and quenched in order to soften it,copper is the opposite of steel! do not use any gasket cement on a copper one piece gasket. Edit, Has anyone checked that the head pulls down all the way to the block without the gasket? are there any alignment dowels stopping the head going down? Has previous resurfacing of the head/block left the studs with insufficient thread to clamp the head fully. A solid copper head gasket like this is usually beyond bulletproof when fitted correctly, and if undamaged can be reannealed and reused even after it has failed! My take is that for some reason or other the head is not clamping down fully onto the gasket?

[@felderup]

the interference fit valve adjusters, maybe a stamped sheet metal fork if they get worn? maybe anneal the whole gasket and see if it's just hardened from the factory, blondihacks has excellent vids for that kind of thing.

[@The_BenboBaggins]

How's the little Perkins coming along?

[@5591408]

Check the compression theory out first Then check the head and block again for flatness and bolt / stud lenght for any elongation. If all OK i would get a new gasket and dry assemble with pressure measurement film made by Fuji, it will show you how much load is on the gasket and where, its an industry standard type of measurement. If you want to know more about it contact me directly as too detailed to go into here 👍

[@MegaReddevil71]

Think the only way is too have the engine into your workshop and check see if everything is right as there could be lots of reasons head not torqued correctly a crack somewhere nuts bottoming out

[@mikec2111]

On gaskets, I would recommend a dry assembly using plastigauge or similar to assess the load applied by the head bolts on the gaskets. (Don’t use torque washers as this still measures pull down on the bolt, you want to know pull down on the gasket) I have come across this problem, sometimes as folk have said because of bolts bottoming out in the hole, lack of thread on the bolt/stud etc. so though the correct torque, it is loading the threads not the gasket(a solution is adding washers.). Leyland had problems also with “soft” head bolts that expanded under a warm engine and released the torque. In some cases, because they did not reach their elastic limit, once the engine was cool, they pulled back. Check torques whilst the engine is hot. An old, temporary solution was to double gasket to see if it extends the time before blowing. Getting new bolts from Leyland did not work but sourcing HT studs elsewhere did. Maybe try changing the bolts/studs. (Question: if four gasket failures, does it always fail at the same point in the same way?)

[@user-or4xn5yz3z]

Is this old Morris head secured with domed head nuts?? Did an old 3 1/2 litre Jag years ago and had same problem. Domed head bolts bottomed out , forgot to add very thick washers!

[@LLIHENYAW]

I noted that you said that the head studs had been replaced - were the top halves the same thread as original?? Obviously the bottom was the same, to screw into the block, but some studs have a different pitch for each thread. If the top thread, for the nut, is a different pitch from original, then the torqueing figures will be incorrect. If they are a coarser pitch than original, then the nuts will have a lower pulling force than the finer threaded original.

[@midgetrace]

I would check the studs, it sounds like the nuts are tightening on the studs not against the head. Try adding another washer.

[@MelSmith-ir4no]

With regard to the side valve. If the head has been skimmed, are the head nuts bottoming on the stud threads?

[@mrcogginsgarage7062]

Wellseal,and fit two head gaskets that should stop it blowing provided the studs aren't playing silly buggers.

[@jdsstegman]

Is the block pulling up around the head studs? Causing a warping issue? The CR is higher than oem, but no that high..... lots of other engine run higher and have copper head gaskets...... Let us know what solves this issue. I would be good to know.

[@carlt570]

ive had issues with various Ford 100e sidevalves, where the heads lift under heavy load (these are competition engines) the block deck distorts where the casting isn't sufficiently strong enough around the head bolt/stud fixing. I'm guessing this is a similar issue you have with the Cossies - hence the long stud conversions ?

[@pauloldfield6968]

If the matting surfaces are correct the head bolts and treads are not pulled it sounds like its the compression ratios are the pistons correct

[@kirwee100]

Looks to be blowing from one side so i suspect the head or block has been machined on a slight angle. Would be worth assembling without a head gasket to check the head sits flat on the block

[@leonboersma2375]

Does it use dowels? If so, maybe check the depth of the recieving side. These old heads could be skimmed a lot making the holes less deep.

[@timevans9710]

No one uses a split link in a timing chain unless it,s riveted over.

[@cossied01]

is the discolouration on both sides of gasket ? IE block side and head side .

[@WilliamSalisbury-lt6kd]

Where did you get your workshop lights

[@iainball2023]

Something holding the head up? Like a dowel pin or something? Running out of threads on the studs before its fully clamped? Other than that, can only rhink the block or head are damaged in some way that it allows the surfaces to flex. Cant see the compression being the problem. All the above assumes the surface finish and flatness are ok. Its one of the above. These things were mended in sheds by men with dodgy rollups flat caps and a hammer for decades.

[@paulgammidge-jefferson9536]

Is there too much oil pressure from the oil pump? Or are the heat torque settings too low?

[@1magnit]

Ongoing headgasket problems will always happen if and when you machine the head face too many times, makes it too thin and it flexes and won't seal.

[@alanlucas2886]

on the rootes engine we used two head gaskets to stop them blowing imps engine i rebuild an side value engine had head and block skimed had a thicker gasket made so try two head gaskets

[@1magnit]

The proper way to use a feeler blade is with 2 of them. One is a go and the other is a no go. The proper spec has a top number and a bottom number.

[@user-sp8oz5qp3o]

Are the head bolts/studs the right length and not torqued before squashing the gasket?.

[@trevor4426]

Put carbon copy paper on the gasket, torque the head down, remove the cylinder head. The resulting transfer of ink from the carbon copy paper will show the clamping pattern.

[@lesleylewis-bm9jm]

Can't believe you cut flywheel off A series with manual transmission to remove it, do you want me to send you a club hammer as your going need something to set the tappets!

[@georgebettiol8338]

When describing the A-series issue - Lee momentarily erred when he informed the viewers on what he did with the 'stuck clutch'. If you listen closely he corrected his second or so earlier statement by stating he cut the clutch to release it from the flywheel - i.e. the flywheel was not cut.

[@tuiscott3719]

The studs are stretching when they are getting warm

[@seriksson9721]

Thicker head gasket or 2 normal ones? It might be worth a try.