• Hi Guest!
    If you appreciate British Car Forum and our 25 years of supporting British car enthusiasts with technical and anicdotal information, collected from our thousands of great members, please support us with a low-cost subscription. You can become a supporting member for less than the dues of most car clubs.
    There are some perks with a member upgrade!
    **Upgrade Now**
    (PS: Subscribers don't see this gawd-aweful banner
Tips
Tips

Experience with Cometic Head Gasket for BN2?

Share this page

B

bj8bn2

Member
Country flag
Offline
I'm faced with a leaking head gasket on my 100...uhhhh! I'm looking for something other than the $300 Denis Welch option and someone told me about Cometic Gaskets. Cometic confirmed they can make the gasket for about $150. Does anyone have experience with Cometic? They focus on gaskets for high performance engines so I'm really interested to see their product.

Related - any thoughts on how to do this head gasket change properly. Other than use a good gasket, should I use copper spray sealant, radiator seal, etc?

Thanks
 
I used copper spray on my gasket on my Hundred, had the head off two or three times, had the car for nearly ten years, didn't have any problems, don't know if the copper spray does the trick, or I just had good mating surfaces and good luck. But I the copper spray in the can't hurt, might help category.

P.S. Just used the standard composite gasket from the usual sources.
 
Last edited:
Related - any thoughts on how to do this head gasket change properly. Other than use a good gasket, should I use copper spray sealant, radiator seal, etc

You might talk to David Knock @ British Car specialties-His father came up with a ffix for this problem.
 
I've used Cometic several times for speciality head gaskets and they are top notch! I have not used them specifically for an Austin-Healey engine, but would have no problem trusting them! I would not hesitate to order from them. Follow their instructions for sealant or no sealant and you should be set.
 
The late Norman Nock and Roger Moment both advocate the use of Wellseal to prevent this notorious leak. Roger wrote up the procedure in his Restoration series in Austin-Healey magazine. Basically, just coat both sides thinly and evenly and install as usual. We used it on our 100M and no leak, but we've only driven a few dozen miles. Wellseal is available from Moss, and possibly your local parts store.
 
Whose gasket did you wind up getting - and did you do it dry or use goop on it - and how has it worked out? After 20K miles my low-tech $50 gasket just blew, so, like you, I'm researching gasket types and sources. Strangely, Cometic told me they don't have gaskets for 100s.
 
NY100M said:
Whose gasket did you wind up getting - and did you do it dry or use goop on it - and how has it worked out? After 20K miles my low-tech $50 gasket just blew, so, like you, I'm researching gasket types and sources. Strangely, Cometic told me they don't have gaskets for 100s.
Click to expand...

It has taken for ever to get the head out of the machine shop for new valves, seats and guides so It's not installed yet. In the mean time I decided to change cams, new lifters, seal up some old gaskets, etc., so the head is not back on yet.

I got the head gasket from VB - plain jane copper version. When I talked to Cometic they said they did make a head gasket for the 100 but it was a copper gasket, not sure why you area getting a different story. I'm going to try to the procedure described by Norman Nock of British Car Specialists, which involves using Permatex Super 300 on both sides of the gasket, the head and the block and using a radiator seal solution to seal up the water jacket. I'm not sure the radiator seal does much but Norman knew his stuff and if he says to do it, then I do it. If you want to read the procedure I can email to you separately.
 
AFAIK, Norman and Roger Moment both recommended Wellseal (I'm sure about the latter--it's in one of the restoration series he wrote for Austin Healey Magazine).
 
Good to hear from you... I was beginning to think this thread was dead. I've got everything off and will pull my head tomorrow. I'm interested in seeing what type gasket it is - and since it lasted 8,000 mi, I'll probably try to get one like it. I've searched the entire SOL and BCF archives, collecting info from hundreds of posts on 100 head issues. The deluxe DW option is considered the best, but I saw no consensus on a SECOND best head gasket type - or on whether to use a sealer, or which kind. (Yeah, I know: Make sure the surfaces are true and pick your poison.) On the bright side, for most of their existence these 100 engines ran okay with low-tech gaskets. In fact, all the manual says is to coat the gasket with GREASE for a better seal! (Talk about simpler times...) And one former 100 racer who ran 11:1 told me he just used everyday Moss/VB gaskets and never blew one. But it sucks to be constantly wondering if the gasket is gonna fail today or wait until you're enroute to Conclave. (Please post the second-best solution here.)
 
Back
Top