Can Not Get Turbo Valve Covers to Stop leaking...

[IAN]

I have Turbo covers on the bottom and have tried several different things and they still leak.

To begin with, I don't overtorque the nuts. I tighten them to 4-6lbs using the cross pattern method.

I always use brand new nuts.

I have tried the green gaskets with the silicone bead as well the thicker PK02 gaskets.

They all leak for me, usually directly through the center of the nylock nuts.

Any thoughts??

The turbo covers are pretty old, and I was thinking they could be warped. Have folks ever machined these flat and had good results?


Thanks,
Ian

[cowtown]

Ian, I'd say you are correct in thinking they're warped. You could try placing them on a sheet of glass to check this out.

Many people true them up on a belt sander....

[tryan]

try a little thread sealant on the cover studs. new washers? nylon lock nuts? check the cover with a straight edge. ( i use hylomar gasket dressing and it seems to work) fix one leak make three more.

[andrew15]

Hey Ian:
I've used the red silicon gasket kits with great success. These are offered by REAL Gasket corp and are made from 1-2 mm thick slicone rubber material and are REUSEABLE. Wayne can probably get them if you call down to Pelican - couldn't see them in the catalog.

REAL Gaskets website:
http://www.realgaskets.com/

Regards,
Andrew M

[tmctguer]

they sound warped to me. get a long straight edge ruler and lay it across diagonally "the long way". you can also lay them on very flat concrete (a smooth garage floor, a long piece of flat board) and see if there is any play.

resist the urge to torque the nuts to the amount used to keep lug nuts secure...........it will only make things worse. you might try just a LITTLE tightening so see if it helps. also make sure the leak is really coming from the valve covers. oil leaks can end at point A, but really start at point Z.

[al lkosmal]

They are probably warped. You can check them yourself, using a staightedge and try to get them flat using a belt sander, but I'd take them to a machine shop and have them checked for flatness and, if req'd, machined flat. Upgrade to the silicone gaskets, etc. and you're good to go.

Al

[911pcars]

Place valve cover on a piece of plate glass with a sheet of wet/dry sandpaper between. Mark w/machinist blue, then rub to see where the high and low points are. Continue until it's flat. A belt sander might be a little too aggressive. A machine shop might be overkill (but nicer).

Sherwood Lee
http://members.rennlist.org/911pcars

[Formerly Steve Wilkinson]

And try the Real gaskets.

Stephan

[Jim Sims]

Also, clean the sealing surfaces on the cam towers. These surfaces should be free of any old gasket material and be free of nicks and gouges. Cheers, Jim

[jazzbass]

I'm with the "they're probably warped" crowd. The only thing I'll add is that I'd check them for flatness on a piece of plate glass, and if warped buy new ones, unless you're a machinist. A new set will run you $100. Machine time to surface grind the old ones will be as much if not more. Ditto for the time you'd spend lapping them flat on plate glass or a belt sander yourself, assuming you value your own time.

[Jim Smolka]

A local wrench removes the studs and then cleans the cam towers until they are spotless. Aftwards, he installs new studs.