Fox T-Bird/Cougar Forums

Technical => Engine Tech => Topic started by: jpc647 on January 25, 2010, 05:57:11 PM

Title: Valve Cover Bolt leaking
Post by: jpc647 on January 25, 2010, 05:57:11 PM
I thought I posted this already but maybe not. The valve cover bolt in the picture of the problem. It has to be that bolt. The oil seems to puddle up in the little groove on the valve cover and then when I drive it drips on the manifold and smokes. I tried thread sealing the bolt, with permatex but it still leaks, the valve cover gaskets were replaced not too long ago, anyone have any suggestions? 

(http://i478.photobucket.com/albums/rr148/jpc647/leakybolt.jpg)

You can actually see some oil in the groove.
Title: Valve Cover Bolt leaking
Post by: jandmmustangs on January 25, 2010, 06:17:35 PM
Possible stripped threads on either that bolt or in the head.
Title: Valve Cover Bolt leaking
Post by: jpc647 on January 25, 2010, 07:59:42 PM
Hmm, I didn't think of that. The bolt goes in and seems to tighten up. I guess I could try swapping two bolts around just for the heck of it to see if the leak changes or whatnot.
Title: Valve Cover Bolt leaking
Post by: vinnietbird on January 25, 2010, 08:12:59 PM
Is it a factory bolt?I've seen some people install bolts that tighten up,but they are just a wee bit too long,so,they tighten in the head,but still not actually holding down the cover.
Title: Valve Cover Bolt leaking
Post by: softtouch on January 25, 2010, 08:58:17 PM
Quote from: vinnietbird;307899
Is it a factory bolt?I've seen some people install bolts that tighten up,but they are just a wee bit too long,so,they tighten in the head,but still not actually holding down the cover.

Good thought.
This can also happen if some oil gets in the hole and the bolt is bottoming out on it.
Title: Valve Cover Bolt leaking
Post by: jpc647 on January 26, 2010, 01:05:54 AM
It is the factory bolt. What I'm thinking is, I still have the v6 motor I took out, the bolts are probably the same size, I'll try to swap one in, if it stop leaking, I'll just look around for the exact same size bolt, but new. I thought maybe there was supposed to be some sort of a washer on it, but none of the other ones had one.
Title: Valve Cover Bolt leaking
Post by: BogusSVO on January 26, 2010, 01:35:13 PM
the VC may be "pulled" around the hole not giving the proper clamp load....
you may want to pull the vc off and flip it gasket side up, and take a smallish ball peen hammer, put the small ball on the hole and whack the first hammer with a 2nd hammer to push the hole back flush or a tad up.
Title: Valve Cover Bolt leaking
Post by: Kitz Kat on January 26, 2010, 03:53:33 PM
Are they aluminum or steel? couldn't tell by the pick. Looks more like a stud hanging out of them. Is that intake polished?
Title: Valve Cover Bolt leaking
Post by: vinnietbird on January 26, 2010, 05:10:21 PM
They look like painted steel covers.
Title: Valve Cover Bolt leaking
Post by: Kitz Kat on January 26, 2010, 05:27:54 PM
They do, but what's with the studs sticking out? Excuse my ignorance, I really haven't been around to many stock parts lately.
Title: Valve Cover Bolt leaking
Post by: vinnietbird on January 26, 2010, 05:34:20 PM
Those are the factory bolts that the plug wire looms slip over.The loom stands up-right on the stud and you would snap the wires into them.
Title: Valve Cover Bolt leaking
Post by: 88CougarGT on January 26, 2010, 06:32:31 PM
Valve cover might be warped.  I would check closely around the bolt hole and make sure that the hole hasn't been pulled down into a mushroom.  If it has, just flatten it back out with a hammer on an anvil.
Title: Valve Cover Bolt leaking
Post by: thunderjet302 on January 26, 2010, 07:14:13 PM
Quote from: BogusSVO;307991
the VC may be "pulled" around the hole not giving the proper clamp load....
you may want to pull the vc off and flip it gasket side up, and take a smallish ball peen hammer, put the small ball on the hole and whack the first hammer with a 2nd hammer to push the hole back flush or a tad up.


+1 I bet that's your problem.

That's the nice thing about cast aluminum valve covers. It's pretty hard to bend the bolt holes.
Title: Valve Cover Bolt leaking
Post by: jandmmustangs on January 26, 2010, 07:57:33 PM
If you find out that its a warped valve cover I have a set of HO cast units (dirty as sh*t) free just cover the shipping.
Title: Valve Cover Bolt leaking
Post by: jpc647 on January 27, 2010, 08:49:12 AM
Vinnie is right, they are the stock (steel, i think)  valve covers. I cleaned them and painted them. I will take the valve cover off in the coming week and look at it, and try to hammer the lip back down.
Title: Valve Cover Bolt leaking
Post by: softtouch on January 27, 2010, 06:28:37 PM
While you have the VC off, check how far the bolt will go into the hole.
Title: Valve Cover Bolt leaking
Post by: dw85745 on February 17, 2010, 01:03:08 PM
I had a heck of a problem with my steel covers.  Finally pulled then and took a piece of double pane glass and used it as a straight edge to check.  Mine were warped.    Use a ball peen hammer and another hammer (put the ball peen ball in the bolt hole from the back side) and use the other hammer to straighten the cover.  Worked great.

Someone already mentioned checking the bolt hole depth.
Title: Valve Cover Bolt leaking
Post by: jpc647 on February 17, 2010, 06:13:43 PM
I think I may have fixed it. I unbolted the two bolts near the problem area, took a 2x4 and used it on the valve cover with a hammer to peen it back down on the car. At 10 degrees outside its too cold to be taking valve covers off and trying to fix them. I then took a correct size tap, to clean out the thread, I put it in and out quite a few times until no more gunk came out on it, put a little permatex on the bolt, and then bolted it down. I let if dry for about 20 minutes and drove the car about 30 miles, no problem. If the problem should occur next time I drive it, I'll let you all know.