Brown Cam Plug popping out

[paulgentile]

My brown cam plug has popped come out twice, with only 4,000 miles in between occurrences.
Had a new one replaced and it seemed to go in quite easily. IMS has been done.
Is there any reason why this would occur?

[JFP in PA]

Originally Posted by paulgentile

My brown cam plug has popped come out twice, with only 4,000 miles in between occurrences.
Had a new one replaced and it seemed to go in quite easily. IMS has been done.
Is there any reason why this would occur?

Two known causes for cam plugs popping: Too much sealant was used when reinstalling the cam covers, causing the adjacent oil return to plug and the oil pushes the plug out; or the AOS is not working properly and the crankcase is experiencing pressure rather than vacuum, which is popping the plug out.

Just as a "by-the-by", never use any type of sealant on the cam plugs.

[paulgentile]

Thanks! AOS was replaced and seems to check out. Likely the other. On the by-the-by, my mechanic did put some sealant on the new plug. Should I replace the plug?

[JFP in PA]

Originally Posted by paulgentile

Thanks! AOS was replaced and seems to check out. Likely the other. On the by-the-by, my mechanic did put some sealant on the new plug. Should I replace the plug?

Yes, and clean all of the sealant off the cam cover as well. These were designed to be installed dry, meaning no sealant of any kind.

[yelcab1]

Originally Posted by JFP in PA

Yes, and clean all of the sealant off the cam cover as well. These were designed to be installed dry, meaning no sealant of any kind.

You do need a thin layer of silicone between the cam cover and the head, because there is no gasket. Am I wrong?

[JFP in PA]

Originally Posted by yelcab1

You do need a thin layer of silicone between the cam cover and the head, because there is no gasket. Am I wrong?

Yes, but only a very thin bead or the excess sealant can get into the oil returns, causing oil to flood the cam cover and blow out the cam plugs.

There should never be any sealant on the cam plugs.

[991gts6s]

back in the day when i had the 996.. the cam plugs leaked and popped out ..
after the the vario cam guide replacement. instead of redoing the cylinder head sealant .. i put a little rtv( Porsche spec brand i forget the brand now)on the plugs and they never gave me a problem ever

[JFP in PA]

Originally Posted by 991gts6s

back in the day when i had the 996.. the cam plugs leaked and popped out ..
after the the vario cam guide replacement. instead of redoing the cylinder head sealant .. i put a little rtv( Porsche spec brand i forget the brand now)on the plugs and they never gave me a problem ever

Very bad idea, they are designed to be used without any type of sealant.

[Jeff Alton]

^^^^ this.