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Wiseco 836 kit - head gasket dilemma

Gabby

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First post for some time but I am now back to putting my K7 engine together. It has a Wiseco 836ccc kit and I have a question regarding the head gasket and the existing oil seals for the oil return from the head. There are eight of these seals which are fitted to steel tubes (the manual calls these a knock pin and stud gasket).

One photo here shows how the seals fit through the stud hole in the stock head gasket, The other photo shows that the Wiseco gasket holes are much smaller. So in this case the rubber would be compressed by the gasket. I expect that the rubber seal would have to make metal-to-metal (cylinder to head) contact to do its job.

Can anybody shed light on this please? Does the hole need to be enlarged to accept the rubber seal? The problem I see then is that there is not much gasket between the stud hole and cylinder. Thanks
 

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I can possibly answer my own question now from an old post on another forum. The K4 to K8 and F engines had a mod to fit those dowels and rubber seals to prevent oil leaks. Someone who seems to be a guru says definitely don't leave the seals out but enlarge the holes in the Wiseco gasket to incorporate them. This means the rubber seals in some places are almost going to touch the gasket metal around the combustion chamber, but it seems to be what is needed. So that's what I will do. But if anybody has had experience with this, would love to hear how you got on. Cheers
 
Thanks hotdog; lots of good stuff in there. As for my question, the answer in that thread seems to be the opposite: don't worry about the knock pins and rubbers. So now I'm less sure. Might toss a coin.
 
You can do either way...either trim the holes out for the knock pins and rubbers or go with out the knock pins and rubbers. I have used gaskets that had the holes big enough to use them and had no issues with leaks, yes the hole is close to cylinder ring but it will not cause an issue IF you use heavy duty studs. Heavy duty studs are a must on ANY 750 motor build even stock size motors...the oem studs will stretch and loose tension and cause oil seeps and leaks. Also be absolutely sure the knock pins do not protrude above the cylinder surface as it will cause the head to not compress the gasket fully. You can assemble with out the knock pins and rubbers If you use heavy duty studs, if you are afraid of oil leaks use a VERY SMALL amount of Hyomar or permatex hi-tac around the stud holes...absolutely no RTV to be used on the 750 motor. If you use the rubbers and the gasket without the holes big enough it will cause the head to not compress evenly and you will have oil leaks. So its up to you...open the holes up or remove the rubbers.
 
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