Imperial Home Page -> Repair -> Engine -> Valve Cover
Tips from Dick:
There is nothing at all difficult about this operation, just undo the cap screws that hold the covers down, being careful not to lose the special shaped piece that goes under each screw to prevent distortion of the sheetmetal cover, and bump the valve cover side to side with your hand until it will wiggle. When you pull each cover, note that some of the old gasket will probably stick to the mating surface of the head, you will have to carefully remove all these particles without letting any of the debris go down into the muck. Then you have to carefully clean the inside of the valve cover, or at least the surface where the gasket seats. Don't clean anything in the mechanical parts, you will only stir up stuff that you don't want circulating in the oil. You'll probably be dismayed at the crud in there, but don't sweat it. Sleeping crud is good crud, loose crud is bad crud!
When you reinstall these covers, and assuming you don't have a torque wrench, you need to tighten them snug, but do not grunt! The torque spec is 15 foot-pounds, so if you happen to have a wrench with a 6 inch handle, just pull 30# on its end to get the right torque. Again, this isn't real tight! If the covers have previously been over-tightened, (which is likely if the last person tried the easy way to stop the leaks), you will have to carefully straighten out the flange so the gasket will set level and seal well to the head.
As long as you are doing this, there's a particular trick I use to check the return drain holes (which if plugged can cause all kinds of weird problems, one of which is leaking valve covers).
The trick is, do one side at a time, but before you do each side, start the engine and let it run for a while at a fast idle. Then, quickly remove the valve cover as soon as you turn it off (it helps to have all the screws backed off to finger tight first). If you have plugged oil return drain holes in the head, you'll find a puddle of oil sitting inside the valve cover, in fact it will probably spill all over the place on you.
This is an indication that you need to ream out the return holes so that the oil will find its way back into the crankcase more rapidly. The hard part is finding the hole, but it will be at the rear of each head, at the lowest point (gravity rules, remember).
You will find its twin more easily at the front of each head, then remember that the heads interchange for each side of the engine, so just picture the mirror image place on the gunky goop filled rear portion of the head you are working on. In other words, observe the symmetrically located hole in the high and almost dry front portion of the head.
Once you've located the hole, take a coat hanger or the like and just push it down through the hole until you hear it scratching the bottom of the oil pan - this means you'll need a piece of wire about 18 inches long. Run it up and down many times, to clear out as much gunk as you can. Problem cured.
Tip from Elijah:
Valve cover gaskets are always a problem on 413/440s because they are so close to the exhaust manifolds. The heat from the exhaust manifolds effectively "cooks" the gaskets!
I've had REALLY good results from Mr. Gasket silicone rubber impregnated Ultra Seal valve cover gaskets. I usually get them from Jeg's Performance: part number 720-5877. These things WORK. I put a set on my '71 three years ago, and still no leaks.
Question from Bill (413):
It is getting close to the time I want to remove my valve covers, and repaint them from the fire engine red someone has put on them, back to the black they're supposed to be. I heard at a recent car show that the 413 four bolt gaskets were getting hard to find. Does anyone know of a source for these?
Replies:
From Dave:
Felpro produce them so they should not be too difficult to find.
From Don:
The valve cover gaskets are the same for any big block, but where are you going to get the Imperial decal on the valve cover as I need a set for my '59 Crown and would like to know.
From Steve:
The valve cover gaskets are not hard to find as they are still being produced (by Felpro I believe) but you do need to make sure you get the four bolt and not the six bolt like the later models used.
Question from Kenyon (440):
I have a 1973 that weeps oil when parked so that if the car sits for more than a few hours, the oil gets down onto the exhaust manifold and then burns off when the engine gets hot. I bought cork gaskets. They did not work better and didn't want to come off without a wire wheel later (YUK). I went to some really neat-o premium thick black rubber ones with pictures of drag cars on the package. I remember being grouchy about the price, so they were "good" ones and they worked for a little while, but now we're back to the same old thing.
I cleaned the heck out of the metal surfaces and don't think that the metal covers are warped from overtightening or anything. The leaks come from between the two bolts above the exh. manifold that are pretty widely spaced.
It seems to me that this should be simpler and more permanent. Am I missing something?
One guy in the Archives used weatherstripping adhesive when assembling. Is "goo" to seal pores the next logical step?
Replies:
From Phil:
Most stock 440's have this problem due to the closeness of the exhaust manifold, which just burns up the gaskets in time. I believe the solution was a small heat shield that bolted on with the valve cover bolts. You could probably make one yourself, or if there is a part number out there someone knows of, could they volunteer the information? It may even be a motor home or RV part.
From Rick:
It also works to silcone the gasket to the valve cover,let it sit over night, then put a layer of silcone on the gasket and put on the engine. The heat shields are a good idea if you can find them or make them. Don't skimp on the silcone. It won't burn off; it is GE or DAP or other brands.
From Steve:
I went to the dealer today to look at the "factory fix" for cooked valve cover gaskets. It is essentially a replacement type exhaust manifold gasket (the ones with a perforated aluminum face backed with gasket material) with a shield of the same material that extends up 2- 2 1/2". The shield is limited to the area between the inner studs on the exhaust ports.
The gaskets were originally intended for motor home use when the "hi-temp" orange gaskets failed to cure the problem.
The gaskets run around $4.50 each. Visually, they're not very appealing, but if you don't show your engine compartment often, it may be a viable fix.
One other item of concern... the package was labeled "Contains Asbestos Fibers". The back (insulation side) is a typical exhaust gasket-type material, with the usual "dusty" feel for this type of gasket. Given the warning on the package, one can only assume that some of this residue is friable asbestos fiber. One would also assume that since these gaskets are for sale in 2002, that the asbestos is not of a hazardous type... although I'm not sure that the non-hazardous types make good insulators... I know we lived with this stuff for years, but I have personally shut down entire assembly lines because of torn pipe insulation in a plant - I'd hate to see a New England or California member have these discovered on his car, and have to pay for abatement... just something that bears checking into before plopping down your 9 bucks.
This page last updated April 16, 2004. Send us your feedback, and come join the Imperial Mailing List - Online Car Club
