While my exhaust is off, I'm going to replace the tappet chest gaskets as they appeared to be a minor leak.

I've ordered new rubber gaskets (12A1175) and new seals for the bolt (12A1176).

From what I've read - there's an art form to tightening the bolts to prevent the gaskets distorting.. but I was wondering if its necessary to also use RTV as well? Seems some people use RTV (or Loctite 518) to hold the gasket in place before the bolt is tensioned...

Definitely harder with the motor in the car, but you'll be OK, just take your time. If it doesn't work the way the internet says to do it, then figure out your own way.

I think I've found that using silicone sealant made them too slippery

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did I tell you that I won a trophy?

I use the same method as the rocker cover - stick the gasket to the cover with a light smear/spray of contact cement and let it dry before fitting.

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Too many cars, and too little time.

Thanks for everyone's replies.. thought I'd provide an update.

I finally fitted the covers on the weekend. I glued the gaskets to the covers first using RTV silicone and bolted to the block for it to set. Then removed and RTV siliconed the cover with the gasket onto the block, and siliconed around the bolts.

Here's hoping it doesn't leak

The silicone red rubber gaskets don't usually leak, even without sealant, it's the earlier convex cover cork ones that do.

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DrMini- 1970 wasaMatic 1360, Mk1S crank, 86.6HP (ATW) =~125 @ crank, 45 Dellorto (38 chokes), RE282 sprint cam, 1.5 rockers, 11.0:1 C/R.