Valve Cover Leaking

[TulsaFred]

Put oil in my rebuilt 1275 today.

I had replaced the valve cover gasket and used Hylomar sealer.

Leaks a good bit from the center of the cover, not the ends where the retaining bolts are.

It looks like the cover may be bowed or warped a little from overtightening over the years.

Is this a common problem? Any fixes/advice?

Fred

 

[Westfield_XI]

Is the gasket cork or synthetic? I believe that the foam type are better at sealing a warped valve cover, also did you let it sit for a few hours before filling with oil? Cleaning both surfaces with solvent and letting the Hylomar set up for a while has helped in the past too.

 

[Guest]

Did you check the cover for straightness? You can bend it back by flippingit upside down and resting the lip on the edge of a bench and tapping gently down on the inside. Easy does it and work your way across from side to side little by little.

 

[dklawson]

Warped (or otherwise damaged from over-tightening) valve covers are not uncommon. There is a fix if you are willing to let your car sit for a day.

Buy a new gasket (silicone, cork, whatever you like). I like silicone.
Remove the old gasket and all its residue making sure that both the track in the valve cover and the head are clean.
Thoroughly degrease the seal track around the perimeter of the valve cover.
Smear a thin film of grease around the perimeter of the head where the seal will rest.
Press the seal down against the head using clean fingers. Get it about where it will be in use. You can temporarily fit the valve cover to get the seal positioned right on the head. The grease will then keep it in location.
Apply a thin bead of RTV to the valve cover and gently put it down on top of the seal resting on the head.
Tighten the fasteners a "tight" "finger-tight". Do not use a wrench.
Allow the RTV to cure over night. In the morning, tighten the fasteners as normal.

Putting the grease and gasket on the head first makes sure that the bottom surface of the gasket is in intimate and flat contact with the head. The RTV in the valve cover track will fill the voids between the top of the seal and the valve cover. Even badly damaged valve covers can be made to work if necessary.

 

[Gundy]

Warped (or otherwise damaged from over-tightening) valve covers are not uncommon. There is a fix if you are willing to let your car sit for a day.

Buy a new gasket (silicone, cork, whatever you like). I like silicone.
Remove the old gasket and all its residue making sure that both the track in the valve cover and the head are clean.
Thoroughly degrease the seal track around the perimeter of the valve cover.
Smear a thin film of grease around the perimeter of the head where the seal will rest.
Press the seal down against the head using clean fingers. Get it about where it will be in use. You can temporarily fit the valve cover to get the seal positioned right on the head. The grease will then keep it in location.
Apply a thin bead of RTV to the valve cover and gently put it down on top of the seal resting on the head.
Tighten the fasteners a "tight" "finger-tight". Do not use a wrench.
Allow the RTV to cure over night. In the morning, tighten the fasteners as normal.

Putting the grease and gasket on the head first makes sure that the bottom surface of the gasket is in intimate and flat contact with the head. The RTV in the valve cover track will fill the voids between the top of the seal and the valve cover. Even badly damaged valve covers can be made to work if necessary.

I just used this very procedure on a leaking inspection cover for my Triumph Bonneville. No leaks. Well...at least no leaks there.