Hi guys,

I need your help. I've have a magna TP (efi) and have had a leak between the rocker cover and top of the engine block for sometime (towards the left back corner, on the cam shaft side). I have removed the cover, inspected the gasket, and it seems OK. For further measure I placed an appropriate silicon gasket maker around the entire edge, while replacing the cover. I did up the bolts and the leak still persists. I have put up with this problem for awhile, however I recently got pulled over and had a yellow sticker whacked on my machine. I need to rectify this problem.

What can I do to fix this problem. Is it possible the cover is slightly warped and prevents a good fit, if so what tips can you provide to help me work out if this is the case.

What else could be the issue? What checks can I make?

All help will be greatly appreciated. Thanks,

TA-man

Your rocker cover might be a bit warped, 20 odd years of heating and cooling cycles will do that.

I think the Astron II covers were cast aluminium/alloy? What you could do is run a straight edge over the sealing face, to see if there's a high point or low point somewhere.

The only other thing you could do is pickup a second hand cover from a wrecker, and try your luck.

I had a similar problem on my 2nd Gen V6, which I could only overcome by using new gaskets, as well as a silicon based sealant.

Try replacing the rocker cover gasket, and ensure the camshaft seal isn't leaking too. You should have a bit of sealant running over the rear end camshaft bearing and 1.5cm out from this too. The same goes with the front end half-moon seal, which must be put in place with sealant running around all edges, the top of it and 1cm either side. Make sure you use sensor-safe sealant, such as black or grey RTV sealant.

It isn't all that common for the cover to warp, although they are prone to cracking if they are overtightened. Also ensure the back thread on the rocker cover that is used for mounting the water pump pulley cover hasn't broken off, as this is also fairly common. If that breaks, it will normally start leaking.

Thanks guys I give it another go, also try my luck at the wreckers.

Cheers.