Under pressure

After my high speed trip back from Gaydon I had noticed some oil leaks from the spark plug side of the engine, it seemed to be coming from the head gasket, not good. However, that side of teh engine doesn't have a reputation for leaking and shouldn't cause a problem. I suspected excessive crank case compression caused by worn rings but this is a "new" engine, probably only 5 thousand miles old. Could it be a blown head gasket?
The only think I'd done to the car that could have influenced this was to fit the catch tank. So I investigated, the catch tank inlet is narrower than the rocker box vent that feeds it, could the step down create a restriction that could allow a build up of pressure? I seriously doubt it but I've gone back to vernting to atmosphere for the rocker cover vent. I didn't want the catch tank to sit there doing nowt so I opened up the vent at fuel pump blanking plate (the pumps now electric and in the boot) and vented that to the catch tank. We'll see if that does anything.
I also did a compression test to see if I could find anything interesting there. I'm never too sure what these readings mean but I'll find out. For now though

  1. 150 psi
  2. 165 psi
  3. 160 psi
  4. 130 psi
  5. 150 psi
  6. 120 psi

That's quite a spread, 10 to 15% is usually said to be acceptable. So I took it out for a blast and of course, it scared me and was great for it! It's one of those things where I think I don't really want to mess with it as it's so damn good BUT it won't get any better by just driving it.

I have all the neccessary to change the gasket but I'm thinking maybe a better copper one should be sourced, rather than the grey one that's on it and that I have "in stock" - I've had issues with those grey gaskets before on the Herald.


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