Valve cover leak or bigger problems?

[atcvette]

I just purchased an 1984 C4. I noticed it had, what semed to be a mild oil leak on the right side of the engine, near the rear and around the valve cover.
However, after driving the car for a bit, I noticed that the leak was alittle bigger than I thought it was. There is no smoke coming from the exhaust, but it looks like its on fire going down the highway. Not sure, if maybe it is build up after a few weeks of sitting or all the fresh oil pouring down on the manifold and exhaust. After looking under the car, I noticed a nice oil coating all over the place, you name the part, it now has a nice new water shield of oil. Not sure what I need to be looking for in terms of fixing it.

The car also got really hot, over heated actually, good thing it was in the low 40s', that helped it cool down quicker. It only did that after sitting idle for about 15 minutes. The fan never came on. Relay? Fuse? Motor?

 

[Edmond]

Fan won't come on until the water temp. reaches 228. They're designed to run hot for emissions.

I think that a valve cover leak is actually quite common for a car this age. With the age of the car, things are bound to happen.

 

[MBDiagMan]

Up until the center bolt valve covers were put on the small block Chevy in 87 or 88, I don't remember which, these things leaked at the valve covers, period. It started in 1955 and only took them 32 or 33 years to fix. Those guys in Detroit are really on the ball.

Have a great day,

 

[atcvette]

thanks for the replies. I am hoping that it is just the valve cover and not a head gasket. I looked under it today, to see where all it was leaking. Everything that was on the ground was near the fire wall back. The rest just dropping off from where it had traveled before. Hope that is a good sign, that it is isolated to just the back/top right hand side of the engine.

 

[JonM]

It could also be the intake manifold gasket as shown on the right in the pic below...you need to clean it up the best you can and locate the leak. You can also get a UV light and get some dye you put in the oil to locate the leak. The kit is about 60 bucks. Let me give you another site that will help you with your 84...http://www.crossfire.homeip.net/

 

[Hib Halverson]

Up until the center bolt valve covers were put on the small block Chevy in 87 or 88, I don't remember which, these things leaked at the valve covers, period. It started in 1955 and only took them 32 or 33 years to fix. Those guys in Detroit are really on the ball.

What a useless response. It's also inaccurate.

Reality is that it's possible to sucessfully seal the earlier valve covers, it's just a little more difficult than those with center bolts and modern gasket designs.

Fortunately, an 84 has cast aluminum covers which are not prone to warpage. You need to pull the covers off, clean the sealing surfaces on the heads and scrape all the old gaskets off the covers.

Then get a set of Fel-Pro's high-performance VC gaskets for SBCs with the "perimeter" bolts. The good guy Fel-Pro hi-po parts are cork with steel "shim" inserts. Bond the gaskets to the covers with Hylomar or weatherstrip adhesive. Wipe a thin layer of RTV silicone on the gasket surface which seals on the head. Let it dry, then install the covers. Do no overtorque the bolts.

Do that and your valve covers should seal for many years.

I have a 400 SBC in my old Malibu and one in my fiance's 82 CE which have valve covers sealed in this manner and neither have leaked since they were installed ten years ago.

 

[Edmond]

Why was the change made from perimeter bolt to center bolt?

 

[atcvette]

I replaced the valve gasket today. Seems to have stopped the ;eak. However, I do have a large amount of oil build up now on the block and other various parts. Is there an engine degreaser that I should use or possible a steam/power wash to get rid of the excess oil?

 

[tigmaned]

theres alot of stuff to remove oil, i have used simple green for some areas, like aluminum parts, foaming engine brite. and what always worked the best was oven cleaner, just don't hit any paint, but the eingine paint is a little tuffer. my 86 vette has the same perimeter bolt valve covers too, and mine are in need of new gaskets too.
as for you over heating, one thing to check is pull the rad upper cover off and clean out leafs and othe crap betweeen the rad and a/c condesnor. C4 suck up everything. other day a buddy came in to my shop with a plastic bag, goes here Ed this was sticking out your vette lower intake area. glad he did i never saw it! if you have no idea when the coolant, T-stat and rad cap wasn't changed, change them! there alot cheaper then a blown head or intake gakset!!

 

[Jeb]

Why was the change made from perimeter bolt to center bolt?

Could it be that it's cheaper? There are less than half of the fasteners required.

Detroit thinks in terms of nickels saved, not dollars.

 

[tigmaned]

they both have 4 bolts per cover.

 

[Jeb]

they both have 4 bolts per cover.

Really? I was under the impression (incorrect I guess) that the perimeter bolt covers had 6 or 8.

My bad.

 

[Edmond]

I guess in theory, the center bolts would provide more even pressure around the gasket, right?