318 Valve Cover Gasket Issues

WJones

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I've been having bad luck trying to fix a bad valve cover leak on my '84 Fifth Avenue. I've replaced them twice with fel-pros that don't have the tabs, and both times they've started leaking oil profusely the next day and I really don't know what I'm doing wrong. I'm probably gonna order the ones with tabs next but was just wondering if anyone has any suggestions.
 

Justwondering

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WJones ...
Let me say first off, I haven't replaced the gaskets on my 87 5th avenue.
however
I have replaced the gaskets on my 79 LeBaron.

Yes, the gaskets needed replacing.
Yes, one leaked afterward.
No, the problem was not the gasket.

My problem was the valve cover was 'bowed' up and not forcing a full, consistent pressure around the entire gasket.

For me, the leak stopped when I did two things:
1. pull the valve cover and lightly tapped the edges straight on the skinny side of a 2x4
and
2. used the triangle shaped valve-cover fasteners instead of hex head.

I'll go look for the link and post it here.

JW
 

WJones

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Thanks! That was pretty helpful. I do think mine are bowed too because I did notice it at the bolt holes the second time around, just didn't pay it much attention. Probably should have though.
Mine do have the triangle shaped washers on the bolts, which I had one oriented wrong on the corner after replacing them the first time and that didn't help.
Another issue with when I did it the first time was I didn't use any RTV. I'm used to aluminum block engines or ones with the slotted, "T shaped" as I call them, valve cover gaskets. So when I redid them last night I used plenty of RTV to help stick them in place and it's nowhere near as bad as before, but a leak is still a leak. It's currently just leaking on the rear of both of them.
And would it be worth it to just buy new valve covers? It's something I've thought about since the paint is all but gone on mine and they're starting to rust.
 

Justwondering

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WJones ...
Bwa ha ha ... and so it begins!

Depends on your pocketbook as to whether you spend the money or not.

Is it probable that a new set of valve covers would reduce leaks -- yes.
Is it possible that you can tweak your old set to reduce leaks -- yes.

Mine still had blue on them and looked decent under all the oil and grime.

I use pinesol to soak my rusty parts in (20 minutes, an hour, overnight... whatever it takes) and then clean it well and apply paint as needed.

But then, I'm saving for a fuel injection solution for the LeBaron so if the money goes to valve covers, I'll never get the fuel upgrade.

Someone will chime in with an opinion on valve covers.

JW
 

WJones

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WJones ...
Bwa ha ha ... and so it begins!

Depends on your pocketbook as to whether you spend the money or not.

Is it probable that a new set of valve covers would reduce leaks -- yes.
Is it possible that you can tweak your old set to reduce leaks -- yes.

Mine still had blue on them and looked decent under all the oil and grime.

I use pinesol to soak my rusty parts in (20 minutes, an hour, overnight... whatever it takes) and then clean it well and apply paint as needed.

But then, I'm saving for a fuel injection solution for the LeBaron so if the money goes to valve covers, I'll never get the fuel upgrade.

Someone will chime in with an opinion on valve covers.

JW
Yeah, the old thing is a bit of a money pit at the moment so I'm not too sure if I wanna go all in on new covers. Plus I'd rather keep it as original as possible, i.e. I'm not gonna get rid of the lean burn, even though it's an absolute nightmare. So keeping the original valve covers would be a plus in my opinion. I'll just have to put some work into it and see if I can fix them without destroying them
 

69-

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Straightening the covers is essential.
Then, apply a thin 'rope' of RTV to the cover, attach a cork gasket and let it sit with the covers weight to have some pressure on the gasket and let it cure.
The triangle helps a lot.
Then, some rtv on the gasket and fasten them very light but tight to the heads.
Thats how I did it, no leaks.
 

Aspen500

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You should also dimple the bolt holes. Set the lip of the cover on piece of wood and use a ball peen hammer at each hole on the bottom side of the lip. Also important to not over torque the bolts. Don't recall the spec right now.
 

Mikes5thAve

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I usually use cork on them with sealant to the valve cover only and don't tighten them down much. Then drive the car and get it warmed up and go over them again. Sometimes you can see a leak and it stops after re tightening. Never had a problem doing it that way.
 
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