Need some help with an oil leak

[waverous]

We have a 1979 GMC 4x4 1/2 ton PU and we have recently rebuilt the SB 350 along with a high volume oil pump. Just tried starting it yesterday and noticed a constant flow of oil spilling out from under the valve cover on the passenger side. The valve covers are new and just a chrome generic dress up model. They have the 3" straps that help anchor the valvecovers under the bolt. I first used a rubber gasket without any gasket sealer thinking that the straps would hold the covers in place. I have since removed the valve cover three times, cleaned the mounting surfaces throughly, replaced and glued new gaskets (rubber, composite, and cork) in place with both RTV blue and red, and I still have the same result - oil running out from under the valve covers onto the headers. There are no visible defects along the head or the cover that would allow this type of leak. Could the increased oil output cause this type of leak? Tomorrow, I am going to try an aluminum cover and see if I can get it to seat any better.
Thanks in advance

 

[88sub4x4]

How much flow are you talking about? Is it a seepage, or a steady river? Are you sure it is comomg from between the head and the valve cover and not from a crack or hole in the head just below the valve cover mounting surface? Just a suggestion!

 

[R72K5]

cover is probably warped junk

and if engine is stock factory then i dont recommend a HV pump, really pointless and will cause alot of oil sucked out of pan and thrown to top end as you have found out

a stock replacement is the best way 20 dollar pump, you only need 7psi per 1k rpm

i always RTV black the cheapy cork gasket to the cover then put it on the engine afte rit sits a bit, and i never ever have any leak problems with covers, so i dunno man,


but good luck

 

[waverous]

Its a steady flow once the engine warms up coming from an area under the valve cover near the front bolt. I haven't checked for pin hole leaks or cracks as of yet.

 

[waverous]

cover is probably warped junk

and if engine is stock factory then i dont recommend a HV pump, really pointless and will cause alot of oil sucked out of pan and thrown to top end as you have found out

a stock replacement is the best way 20 dollar pump, you only need 7psi per 1k rpm

i always RTV black the cheapy cork gasket to the cover then put it on the engine afte rit sits a bit, and i never ever have any leak problems with covers, so i dunno man,


but good luck

Thanks for the information - the HV pump is used because the truck will be towing and carrying stuff quite often so we just thought it would be a little extra protection

 

[RustBuket]

That happened to me. Turned out I had the valve covers on backwards. One side of the valve cover has a flange that is supposed to go over the edge of the motor and the other is flangless and goes up against the intake manifold. When you switch them around, the flange presses against the manifold and doesn't all the valve cover to seat all the way. Hope this helps.

 

[sweetk30]

v c info

the crhome looks real good sitting there. untill you fire it up. ditch those things asap. friend did same thing and tranny wouldnt stop leaking till put stock pan back on it. his v.c.s are leaking just not as bad as yours .

 

[waverous]

Thought of that after the first time but I had them mounted the correct way

That happened to me. Turned out I had the valve covers on backwards. One side of the valve cover has a flange that is supposed to go over the edge of the motor and the other is flangless and goes up against the intake manifold. When you switch them around, the flange presses against the manifold and doesn't all the valve cover to seat all the way. Hope this helps.

 

[85mudblazin]

are you sure you didnt tighten them down to much?? on a sb350 there is no bolt in the back so if you tighten the middle bolts to much the ends of the cover want to raise up, just something you might want to check

 

[camiswelding]

I would initially suspect cheapo covers... even with all your preventative efforts they are usually junk.... I use good silicone gaskets... gm or fel pro... they are worth the extra money...

as for valve covers I like gm aluminum.. or new OEM steelies..

Im going to bet youll find those covers are at fault.... I chased an oil leak like you describe before I threw a set of those away...

problem solved

cam