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MG Midget and Sprite Technical - Victor Reinz composite cylinder head gasket

I keep reading conflicting advice on fitting these gaskets (small bore for 948cc).
Should a sealant such as Wellseal or Loctite be used with these composite gaskets or should they be fitted dry?
This is so confusing!!
Thanks
Les Robinson

Les
I have fitted a couple of cometic HG’s on folks Sprites. I fitted them dry.
Years onward they have not given trouble.
Alan Anstead

Like Alan I've fitted a number of Cometics, none of which have subsequently given trouble.
(Mini, a couple of Pinto engines and a small block Buick aka Rover V8)
However...
All those engines had freshly machined head and block surfaces. I fitted the gaskets dry and degreased the metal surfaces. Cometics are reputed to be a bit demanding in that area but I've never used one on "dirty" engine so I can't comment.
Back "in the day" when my old man was showing me what to do (50 - 60 years ago) he would wipe a thin coat of grease on a new gasket to help it seal.
For context though, that was a time when it was common to decoke your engine once or twice a year because fuel quality was so poor. So you slapped on whatever gasket you got from Brown Brothers or whoever and hoped for the best.
The cheap gaskets then had to cope with surfaces that were dinged, scraped, scarred, burned and eroded.
Nowadays we are a bit more sympathetic and gaskets are more expensive so we want them to last longer.
I've never used Victor Reinz gaskets or even heard of them but there's options out there. For what it's worth I looked online and the immediate answer I had was that they are designed to be fitted dry and that chemical sealants may actually degrade them.
IDK...
IMO I would opt for dry fitting as a default on a composite gasket.
HTH.
Greybeard

As per Grey- I can remember my old man greasing up gaskets to seal them, I still do it now on things like rocker cover and sideplate gaskets--glue the gasket to the cover with contact cement then grease the face, so then the cover can be removed complete with the gasket and reused,- but for actual headgaskets he always painted them with silverfrost which was a metal based silver paint--it really sealed them up. I'm a Cometic fan as well but always give them a light spray of Coppercoat more out of habit than anything, but on their Lotus T/C mls gaskets there isn't any embossing around some of the coolant holes so I spray them just for my own peace of mind -probably not necessary but it's a case of always have-always will for me.
As far as the Victor Reinz gasket goes, their mls gasket would be similar to cometic's gasket so me personally would give it a spray-- but their composite gasket is already sealed up in the composite material itself and I'd agree with Grey and fit it up dry, the last thing you need is your sealant choice reacting with whatever they've used on the gasket

Not sure of the instructions from V/Reinz but a lot of headgaskets now come pretreated with sealant and need bringing up to operating temp. and cooking in to activate the sealant before adding the coolant. So the process is run it to get it hot, retension, let it cool right down, retension---------then add the coolant.

Years ago working on ultra high compression chev race engines we'd get a cometic mls gasket and remove the rivets then remove the centre out of the gasket leaving the thin embossed shim off either side of the gasket--then use one of these shims on each bank as the headgasket---They were bullet proof but yeah, the surfaces had to be spot on.

willy
William Revit

Willie, I never even noticed any lack of localised sealing provision around coolant passages, or even oilways for that matter. Never gave it a thought.
It's a bit of a minefield to my way of thinking. Dry or oily? No wonder Les has some confusion - i don't blame him, so do I.
I don't remember Cosmetics having any comprehensive instructions included, which is a bit unhelpful. Fortunately, Google knows everything but it pays to be very selective as opinions are like aresholes. Everyone has one and what comes out of them is often not much different!
Confusing indeed.
The opinions I trust are people like you with decades of doing it in the real world and getting it right (and occasionally wrong, which has its own value).
Curiously, some manufacturers specify sealant, even on HGs. Caterpillar for example specify Black grade Wellseal for some of their diesel HGs, which is why I still have it in The Shed. It's also the only thing I ever found that would seal an early 80s Honda cam cover 😉
Greybeard

>>>and need bringing up to operating temp. and cooking in to activate the sealant before adding the coolant. So the process is run it to get it hot, retension, let it cool right down, retension---------then add the coolant.<<<

Forgot to say that I would have my heart in my mouth doing this! I'm certain you're right Willie, but it's definitely something that would make me cringe. I mean, what could possibly go wrong.
Hahaha!
I've never been brave enough.


Greybeard

After much thought and faffing about I’ve decided to fit the gasket dry - is this the right decision, who knows!
Next issue is the tightening of the nuts.
Is this the correct procedure:-
Assemble everything and torque up the nuts. Do not add coolant.
Run engine till it’s hot then retention the nuts, back off 1/2 turn first then re torque - all while engine is still hot.
Let engine cool off, leave overnight. Back off nuts by half a turn then re torque.
Then add coolant and I’m ready to go.
Les Robinson

Maybe some useful information here https://www.victorreinz.com/en/service-downloads/practical-information.aspx .

If running up to temperature dry I would want to have an accurate thermometer handy to check the head/block temperature doesn't get too hot, would really like to see the installation details from the gasket maker all the same. I've only run engines dry initially for brief periods and never up to working temperature so haven't done the heat/re-torque type of HG install.
David Billington

Les--Just to clarify----
-I've copied your post just to keep it together

"After much thought and faffing about I’ve decided to fit the gasket dry - is this the right decision, who knows!
Next issue is the tightening of the nuts.
Is this the correct procedure:-
Assemble everything and torque up the nuts. Do not add coolant.
Run engine till it’s hot then retention the nuts, back off 1/2 turn first then re torque - all while engine is still hot.
Let engine cool off, leave overnight. Back off nuts by half a turn then re torque.
Then add coolant and I’m ready to go."
-------------

Personally I think you've decided well to fit it up dry assuming that it is the 'composite' gasket you have.

The engine doesn't have to get hot hot, just hot enough to get it toasty-- I normally just run it until the head feels hot by hand--as in start it up and keep having a feel somewhere like around that centre headstud/sparkplug area or even around the front near the thermostat area--you'll be able to feel it getting warmer and warmer until it's getting hot,ish to touch,enough that you can't keep hold of it-- that's plenty hot enough, it doesn't need to get right up to temp.
Then retension--one at a time--I wouldn't go back as far as 1/2 a turn, just enough to make it move a degree or two to crack it and know that it will be free to move up to retension then on to the next one---don't let them all off to retension just one at a time in the sequence.
Then tomorrow-cold-crack off and retension one at a time again -reset valve clearances -fill the coolant and you're good to go.

William Revit

IIRC 60C for metal is about the upper limit of what people can touch briefly without problems, so not full engine temperature.
David Billington

From what I can gather, the Victor Reinz composite head gasket (part no: 61-35330-00) does not have a sticky adhesive on its surface. Instead, the surface has a special dry coating (or impregnation). This coating stops the gasket from soaking up oil and water - this came from Google!
Therefore do I run it without coolant initially to get hot or fill it after installation?
My current, revised , plan is to fit the gasket, torque up the nuts, fill the coolant, run up to temperature, let it cool off overnight then re torque. Run for about 100 miles or so then re torque. Of course setting the tappers each time.
Having said that my plan could change again!! Hopefully not as want to get this job finished.
Les Robinson

most if not all composite gaskets are made from an impregnated material , as you say to prevent coolant/oil wicking through them.
I'm unfamiliar with the Victor Reinz gasket, so can't directly comment on that particular gasket as far as running it up dry---maybe message them for comment if there's nothing mentioned on the packet the gasket came in.
I know some Payen gaskets state it in their instructions and will weep until they're retensioned if you prefill them with coolant.

Your latest plan sounds fine, specially the retension after 100 mls
If you are going to fill the coolant you could always do your initial tension up then wait for 1/2 an hour of so then tension it again.
This used to be the method for Pinto Escorts and they'd always move just a bit.

willy
William Revit

Head gasket fitted. Running to temperature with coolant and noticed that there is water coming through one of the head fixing nuts!
Les Robinson

Right, I have a plan.
Going to strip it all again - 3rd time! Will put sealant on all the studs where they screw into the block - any recommendations?
Also any suggestions for the best make of head gasket. Currently have a Victor Reinz but not used it in anger yet. Do have a BGA gasket as a spare, are these any good?
One day I’ll get this bleeding gasket sorted or is it just a dream!
Les Robinson

On a 948 I used Draper Hydraulic Seal on the head stud threads. I also fitted (supplied by the owner) an uprated head stud kit from Minispares with hardened washers.
Alan Anstead

Would you seal and fit all studs prior to fitting the gasket.
I also have the Mini Spares updated studs, been in for about 10 years
Les Robinson

Meant uprated studs not updated!!
Les Robinson

From what I can gather, on the 948cc engine the holes in the block for the 5 short studs (spark plug side) are through holes into the water chamber and hence need sealing, that ties up with the spare Goldseal block that I have. I think the holes for the 4 long studs are blind holes - need to check that.
On the 1098 engine all the holes are blind holes.
That’s my understanding, please let me know if I’ve got it wrong.
Les Robinson

Just thinking, as it’s just the one stud that’s weeping, can I remove this then add sealant and put it back in then re torque the nut. I won’t be able to dry off or clean the thread in the block though.
Or will this mess up the loading of the head gasket ?
Les Robinson

Worth a try Les--maybe clean the stud up and apply the sealant to the thread and don't screw it in straight away, let it dry off a bit, might make it stay in place better when you screw him back in --- may as well take some time and do the 5
William Revit

I could just do the offending stud. All the others seem ok, they have never had sealant on! How about using PTFE tape?
Les Robinson

I remember using Loctite 243 'lock n seal' many years ago, when I had a similar problem with my A35 engine.

I don't think PTFE tape worked.
Dave O'Neill 2

I have some Loctite 243, that’s Lock N Seal isn’t it, blue liquid.
Or is there a better alternative?
Sorry for so many questions!
Les Robinson

AFAIK 243 is a threadlocker. It may have incidental sealing effects but I'm guessing that locking the threads is not your objective.
Loctite do hydraulic sealants and thread sealant as well, some of which are heat tolerant.
542 or 572 might be a better bet.
Greybeard

Must admit I assumed it was a thread locker rather than sealant.
I have ordered some Permatex sealant to use.
Took stud out to have a look although have put it back in and torqued it up prior to getting the sealant, hopefully tomorrow.
Les Robinson

Good luck 😁
Greybeard

All 5 studs that break through to the water chamber are all now sealed using Permatex. Got to give it 24 hours before putting coolant in and starting it up. Hopefully it will all be ok.
Now onto the next problem- see new topic, angle drive.
Les Robinson

Ran engine this afternoon, got to 175 deg.
All seems ok.
Will re torque the head tomorrow.
Les Robinson

This thread was discussed between 09/06/2026 and 23/06/2026

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