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Changed Valve cover gaskets - Still leaks??

I just had my valve cover gaskets changed because I had oil leaking from two of the bolts on the passenger side, the two that are closest to the rear of the car.

I used the gaskets from our Host that had the silicon bead or what ever it is and now I still have oil drops on the same two Bolts. Very Frustrating. There is no oil leaks anywhere else or above these two bolts. It seems to be dripping down these bolts???

I know 99% of these cars leak but my car was rebuilt about 20,000 miles ago and other than whats described above the car does not leak oil.

Any thoughts or help would be appreciated.

Best regards,
Booney1golf
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Old 04-10-2009, 12:47 PM
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Torque values are important,..what were thay?

Secondly: a GOOD inspection of the rockers (any leaks) would be in order upon VC drop,..

Maybe, the leak is from somewhere else? Not sure.....But I would check the rocker inetegrities (leaks) for one.


Good one,...


Doyle
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Old 04-10-2009, 01:04 PM
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You may have warped covers. Do you know the torque on these? It's really low. Just a knob on the socket will get them to the right torque. When I use a ratchet, I use a 1/4" drive and don't go hard at all.

For the technical side, I think the torque is 6 foot pounds. That's 72 inch pounds if you have an inch torque wrench. At only 6 ft lb, I don't trust a 3/8ths drive torque wrench.
Old 04-10-2009, 01:10 PM
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So if the mechanic over tightened the nuts this could cause a leak? New nuts were included in the gasket kit. Why would only two leak? The same two that leaked before changing the gaskets. He said the old gaskets were brittle from heat.

If the leak were the covers (they are turbo covers) wouldn't the leak be around the seam and not on the ends of the bolts. The seam is dry.

I was not there to inspect the rockers but the shop is very reputable and also the engine was rebuilt 20,000 miles ago.

Very confusing / frustrating!!!

Best regards,
Booney1golf
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Old 04-10-2009, 01:31 PM
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Did they use new crush washers under the nuts?
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Old 04-10-2009, 02:32 PM
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I second about everything written here.

FIRST, use a set of NEW nuts, washers and gasket (sold by our host).

NEXT, torque the nuts to 6 lb/ft in a staggered pattern like when you tighten your wheels.

If a the leak persists, you may have a warped valve cover.

Good luck!

Mike
Old 04-10-2009, 06:14 PM
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I found it was important to heat cycle a few times, then go back and re-torque.

An inch/pounds tool is best.

I think the factory gaskets work best.

Check the mating surfaces for cleanliness and the lower covers for flatness. I prefer the wifes granite counter top with two sheets of 400# wet/dry sandpaper to check & clean the covers.

Send wife to movies first, otherwise the process can become very noisy.
Old 04-10-2009, 08:29 PM
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I have the exact same leaks out of my lower turbo valve covers. They drip off the studs. I have replaced the gaskets twice, used haylomar, checked for warpness, and torqued them correctly.

Mine still leak!!!!! No idea why
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Old 04-10-2009, 08:43 PM
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It sounds like you have warped valve covers. Instead of using your granite counter top which could cause significant marital problems, I used a cheap piece of glass (old mirror) and 400 grit wet-dry sand paper. It takes a long time to true them up, but well worth the effort. If they are really bad, start with 200 grit to remove more material. Having true valve covers is more important, IMHO, than new nuts or washers. I run standard gaskets with no leaks.

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Old 04-10-2009, 08:44 PM
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I just changed my lower turbo valve covers today. I had oil dripping on the first upper and second lower nuts on the driver'side. I used the bedded silicon gaskets from our host. My previous gaskets were the same. I hope this works. I did see oil seeping from the upper corner above the left side of the valve cover but I have no idea where it is coming from. I checked my upper valve covers and oil regulator gaskets they look good. Is it possible oil is seeping from the topside so slowly it doesn't puddle? By the way my turbo covers are only 4 years old. How do they warp so fast?
Old 04-10-2009, 10:13 PM
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the top covers go bad also. the most likely culprit is a rocker shaft that has moved in it's bore. many re builders do not torque the rocker shafts to a high enough value then they come loose and move in their respective bore. the shafts should be installed dry and torqued to 21 foot pounds.
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Old 04-11-2009, 05:00 AM
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I also have the same leaks from the bolts but the other day i found that at the top of the engine drivers side toward the front at the head ,there is a bolt that was seeping ..Saw this with a mirror ...just had to retighten and the major leak is gone ..as for the bolts leaking i still have that ..
Old 04-11-2009, 07:33 AM
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After completing my rebuild I had no leaks through the bolts.

But after my first valve adjust I had the same issue of oil leaking through the bolts (studs). I pulled everything off again and really cleaned every surface - the gaskets, cam housings, studs, etc. Obviously I could rule out a warped cover b/c it wasn't leaking previously.

After putting everything back together I no longer have leaks. I used the same nuts and crush washers too - only b/c they were barely used.

I use the full silicon gaskets which are thicker than the others - 4 or 5 inch pounds of torque. Like others said, check your rockers and then tighten cover nuts in a zig zag pattern. I work my way from the inside to the outside - middle, right, left, further right, further left, etc.
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Old 04-11-2009, 08:42 AM
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Quote:
Originally Posted by kodioneill View Post
the top covers go bad also. the most likely culprit is a rocker shaft that has moved in it's bore. many re builders do not torque the rocker shafts to a high enough value then they come loose and move in their respective bore. the shafts should be installed dry and torqued to 21 foot pounds.
21 ft-lbs?? Listed where?

Pinch bolt for the rocker shaft torque:
Wayne's book: 13.2 ft-lbs
Anderson: 15 ft-lbs

It depends a little on the condition of the seat.
I prefer a dab of oil on the expansion seat and nut to ease the wedging effect when tightening the Allen bolt.

Always check the position of the shaft when adjusting valve clearance.

Been re-using the same OEM gaskets for the last 3-4 oil changes, no leaks.
It's essential to really clean the mating surfaces and ensure that the valve covers are not warped.
To prevent the gasket from sticking (The annoying left-over), I smear a very small amount of grease on both sides of the gasket and it comes off in one piece the next time.

New Alu crush washers and Nyloc nuts should prevent leakage around the studs.
Torque the nuts from the center out; I do it by feel.
Re-check after some running-time and tighten them just a bit more.
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Old 04-11-2009, 10:34 AM
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my guess is you have oil leaking from some of the rocker shafts
you can't see oil leaking from them when everything is in place, gravity takes it to the lowest spot and air currents and heat move it and wick it around from there.

i have reused my silicone valve cover gaskets around 5 times now.
i love them because they can be reused over and over, and mostly because you never ever have to clean graphite and gasket material or anything else off the flanges after taking the covers off.
i just wipe any oil and dirt off of them with fast evaporating laquer thinner on a rag before reinstalling them. they won't swell or deteriorate if you clean them that way.

i don't overtighten them, just snug them until i just start to see the silicone being compressed outward next to a stud. the aluminum washers do not get squished at all at this low a torque so i reuse them with no leaks.

my car always had oil dripping from the botom of the cam tower and bottom nylocks... until i put rocker shaft oil seals in the last time i had them all out.
now the motor has no oil leaks.
Old 04-11-2009, 12:02 PM
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Old 04-11-2009, 12:02 PM
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