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Leak on DOHC Valve cover

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On the passenger side of my EJ25D heads, it's leaking from the lower half-moon on the back. When I put the heads on last year I re-used the half-moons, used that 'Seal-All' stuff:banghead:, and used a new valve cover gasket.

 

It leaked shortly after that so I went back in w/NEW half-moons and the ultra-grey this time - used sparingly, w/the same VC gasket......

 

It's leaking again! WTH am I doing wrong??

 

I saw this POST , which sounds similar.

 

 

Thanks,

Td

Check your pcv system and make sure that the valve and hoses are clear. You may be building up too much pressure and forcing the leak.

 

Also, did you put some of the sealant on top of the half moon before you put the cover back on. I always do that to keep it from making a leak point.

 

Cheers

  • Author

Check your pcv system and make sure that the valve and hoses are clear. You may be building up too much pressure and forcing the leak.

 

My car is turbocharged, so the 'too much pressure' makes sense - good catch. I'm redoing my PCV system tonight.

 

Also, did you put some of the sealant on top of the half moon before you put the cover back on. I always do that to keep it from making a leak point.

 

Cheers

 

I didn't put any sealant on the exposed side of the half-moon. I thought the VC (valve cover) gasket would seal that.....but I can 'see' where there might be leak point on each end of the half-moon if there's a gap where the gasket/VC/half-moon all come together.

 

Thanks much for the feedback.

 

Td

I put a dab where the half moons meet the head and gasket. Just like in the corners up by the cam seal(best way I can think to describe it).

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