Leaky Valve Covers

[Gregtx]

I've been chasing a leaky valve cover issue for what seems like months now. I'm now on my 3rd set of valve covers and I can't even tell you how many valve cover gaskets. I finally bought some of the fabricated, tall, aluminum ones with the thick flange. I had to modify them slightly to fit, but they're going on great now. I've got a roller setup, so I had some clearance issues with the baffle that I had to accommodate for as well. I went the double gasket route rather than the valve cover spacer, although I may end up breaking down and getting the spacers at this point.

Where I'm CONSTANTLY leaking is at the back corners of either side towards the outside of the motor. I'm guessing that this is where the most oil collects when the motor is running. I've tried just about everything it seems. This last go round, I built the double gaskets first by "gluing" them together with permatex ultra black and sandwiching them between some heavy boards and let that set overnight. Then, I cleaned up all the surfaces with a roloc pad, wire brush, steel wool and finally acetone. They were CLEAN. I then installed the new gaskets with ultrablack and torqued the covers down to spec. I waited a full 2 days before trying to start it again. STILL LEAKING!!! These are the composite cork/rubber gaskets.

I shouldn't be fighting any cover deflection issues. Is it the ultra black that is giving me grief? Should I be looking at another sealant? I've tried solid rubber gaskets, no sealant, using weather stripping adhesive instead of ultra black to "glue" the gaskets together, just about everything I can think of. What gives? I'm very determined to get this damn thing to stop leaking, and I'm not going to accept that I should just park it in the grass. LOL!

[Chopperman]

I finally got mine to stop leaking by doing the following:
1. Restricted oil flow to rocker shafts, this eliminated the overflooding of oil in the head
2. Straightened my stock covers
3. Cleaned all surfaces with brake clean
4. New rubber felpro gaskets
5. Thin layer black of rtv on both sides
6. Valve cover bolt clamps on lower bolts

The biggest thing was controlling the flow of oil to the top end. Run the engine with the cover off, you'll be amazed at how much oil is floowing through there. I'll warn you - restricting the oil is a controversial topic though. For me, I was able to control the flow enough that it wasn't flooding the valve or spilling over the head.

[Manny]

My 360 wound up being the intake was leaking at the rear corners. I resealed the valve covers twice and then finally found the leak with the mirror. What motor are we dealing with here?

[colnago]

This last go round, I built the double gaskets first by "gluing" them together with permatex ultra black and sandwiching them between some heavy boards and let that set overnight.

Double gaskets? I've not heard of this before. Is this an "FE thing?" Do you literally mean gluing two gaskets together, to make a double-thick gasket?

Sorry, my ignorance is showing.

Joseph

[Gregtx]

This is an FE 390.

I haven't added the oiling restriction to heads, although I did consider it. I'm just afraid to start mucking around with the factory oiling in the top of the motor, although I don't know that it would be a huge issue (other than I'd have to take the heads back off to do the machine work).

As far as the double gasket is concerned, yes, I am essentially "gluing" two valve cover gaskets together to raise the height of the valve covers. This is a pretty common (albeit ugly) solution to clearance issues when you install a roller setup because it's quite a bit taller.

I like the mirror idea. I just happen to have a boroscope, so maybe I can actually use that to help me see what is really going on.

[tnlprt]

The heads do NOT have to come off to restrict oil to the rocker arms

All you have to do is pull the rocker arms and drop a holley carb jet into the oil feed hole under the rocker arm pedestal

[Gregtx]

Well the leak is the result of the dual gasket per side "fix". The oil is seeping slowly through the two gaskets, despite having cemented them together with Ultra Black. I'm going to order a set of the 1/2" valve cover spacers with the gasket lock channel in them. I'm hopeful that finally solves the issue. I'll also look into the oil restrictors with the Holley jets. I've got a few of those laying around, so maybe I can make that work.

[Ranchero50]

My fix for oil leaks is to get rid of the gaskets. Remove them, clean both surfaces with brake clean until a white rag comes clean, then a 3/16" bead of Permatex Ultra in your favorite color to once surface. Install covers and tighten bolts. With cast parts you shouldn't have warping issues and the silicone will allow for some difference in the parts.

I use this method to install the walls on our folders and it works pretty well.

[Manny]

My fix for oil leaks is to get rid of the gaskets. Remove them, clean both surfaces with brake clean until a white rag comes clean, then a 3/16" bead of Permatex Ultra in your favorite color to once surface. Install covers and tighten bolts. With cast parts you shouldn't have warping issues and the silicone will allow for some difference in the parts.

I use this method to install the walls on our folders and it works pretty well.

Never thought about that one should work fine. I have to say WOW interesting machine!

[colnago]

Hey, I'll be impressed AFTER he fits it under the hood!

Joseph

[Ranchero50]

All that work was for an oil leak believe it or not. Job was done about a year ago and they rolled the seal putting the bearing box back onto the shaft. It wasn't terrible but took a couple days working solo and answering other pages to pull two big gears off followed by the bearing box. Replaced the seal and bearing before putting it back together. 99% well thought out rigging and 1% bumping with a dead blow sledge to get the gears back on the shaft.




This press / folder can process an entire Women's Day magazine in one pass with 6 deliveries each compiling a different section of the magazine. An offset press does the covers and they are perfect bound in finishing.

Not the same machine but this is a picture of our printing presses that print on a 108" wide web of paper and the folder processes it into signatures that are either saddle stitched, prefect bound or inline stapled (at the folder) and shipped direct. This one does National Geographic and ESPN's mag.


And yes, we have a ton of oil leaks.

[fastEdsel]

I agree with throwing out the gaskets. Clean off the head surfaces and clean thoroughly the valve covers. What I did was put a 3/16" bead of "Right Stuff" on the valve cover side. But before you put on the parts, clean all the surfaces with Brake Clean and compressed air. Place the covers on and hand tighten the screws plus 1/2 turn, do not torque them to the bottom, the Right Stuff will hold them in place. Leave it for 24 hours. This worked for me but still have a leaky intake on the bottom corners of course. My plan is to remove this huge big 4 barrel cast iron intake and replace it with an aluminum one. Some one out there will tell me that will make a difference hopefully. On our aircraft engines we use no gasket sealer on the rocker covers. The Lycoming engine gaskets are only about 1/8" thick and the radial engines are slightly thicker. The covers are torqued to the point of looking squishy around the edges but the manual says that is enough and seems to work well.

[WhitsEnd]

Doubling the gaskets is asking for trouble. With an FE, the most common valve cover leak is not a valve cover leak. Are you sure it's not coming from the intake/head/block interface and wicking to the edge of the covers?
How is the intake to head interface under the valve cover? Nice and flat? This is a common issue with an FE. If not perfectly flat here, a smear of Right Stuff is in order. If the mismatch is more than .080" or so, I suggest removing the intake corks if they are holding up the intake too much: I use Right Stuff exclusively at the front and rear of my intakes on FEs.
Second most common problem is over tightening. If you have fabbed covers with thick flanges, you should not need load dispersion clamps (although I use them with stamped steel covers).
Restriction of oil to the top end is a good idea, as long as you have tight clearances on the shafts and rockers. With worn shafts, it doesn't really matter because the oil isn't getting everywhere it should anyway. Another potential issue is that some guys will add a pushrod oiling valvetrain and keep the rocker shaft oiling maxed out. One or the other, please. (And parts designed for Chevies should stay on Chevies)

Use thread lock on the bolts and assemble everything dry and super clean (I use and suggest cork gaskets). No lockwashers. Tighten only slightly more than finger tight with a 1/4" drive and let the cork take a seat overnight before you introduce heat.

Do not glue the gasket to the head. You will eternally regret it and it is completely unnecessary.

[Manny]

I may actually try sealing the M/T valve covers on the bronco...

[Gregtx]

The double gasket was the problem. I went and bought a set of the Medice spacers with the milled channel in them to help the gasket seal. They worked GREAT!!! No more leaks. I'm happy as can be with those.