Author Topic: Changing Valve cover gaskets??  (Read 4739 times)

Offline Rockin77

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Changing Valve cover gaskets??
« on: September 26, 2007, 08:43:32 pm »
I haven't done this before but oil has been leaking for the back of my valve cover. When i change it do i need to drain the oil first?
1977 GMC High Sierra 25

Offline 1973c20

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Re: Changing Valve cover gaskets??
« Reply #1 on: September 26, 2007, 09:27:40 pm »
Nope, the oil drains down back towards the bottom when the engine is off and shouldnt pool up there unless the passages get clogged. I'm in the process of changing mine myself cuz i had the same problem. Also make sure you get some good quality gaskets, such as rubber. Cork gaskets are cheaper but aren't as good at sealing from what i've seen.

Offline 79apache

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Re: Changing Valve cover gaskets??
« Reply #2 on: September 26, 2007, 10:58:41 pm »
Clean your mating surfaces well, be careful not to bend the cover, and don't leave ANY of the mess in there.

I like to run a very thin bit of "blue goo" over both sides of the gasket to fill any tiny gouges I may have made cleaning the mating surfaces. Not much, just enough to spread equally over the gasket with my finger.

Probably overkill but it makes me feel better. ;D

Offline Rockin77

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Re: Changing Valve cover gaskets??
« Reply #3 on: September 26, 2007, 11:09:53 pm »
Thanks for the tips. I really appreciate it. Also how hard is it because the air condition bracked is in the way??
1977 GMC High Sierra 25

Offline 1973c20

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Re: Changing Valve cover gaskets??
« Reply #4 on: September 26, 2007, 11:11:21 pm »
Um i don't have an answer for that because i don't have air conditioning  :P

Offline Captkaos

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Re: Changing Valve cover gaskets??
« Reply #5 on: September 27, 2007, 09:56:02 am »
You will probably end up having to remove the brackets for the A/C, they make it hard.
I wouldn't recommend putting gasket sealer on the head side of the motor.  Most problems with leaking valve covers are over tightening.  They only need to be a little tight, especially with a cork gasket, I don't have the torque specs, but I am thinking something like 15 INCH/lbs

I would put a little sealer on the valve cover (if that is what you were talking about) to easily put it back on without holding it.

Offline Lt.Del

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Re: Changing Valve cover gaskets??
« Reply #6 on: September 27, 2007, 11:05:08 am »
I echo Chris in not over-tightening the bolts...it doesn't take much pressure to clamp it down well--and it doesn't take much to snap off a bolt in the cylinder head. Remember, if you have a torque ratchet, it is inch pounds--not foot pounds!

You can easily tell if you must remove brackets--if you can't get to the bolts on the valve cover, you'll at least have to loosen the brackets some and tilt them out of the way to get to the valve cover bolts. If oil spills out of the valve cover when the engine is off, you have more major concerns.  You shouldn't have to worry about that. 

Offline Rockin77

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Re: Changing Valve cover gaskets??
« Reply #7 on: October 14, 2007, 03:03:34 pm »
I changed the gaskets and it still leaks at the back or the driver's side valve cover. I didn't over tight them what could be the problem?
1977 GMC High Sierra 25

Offline 123 pugsy

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Re: Changing Valve cover gaskets??
« Reply #8 on: October 14, 2007, 06:22:22 pm »
If your covers are thin stock metal covers , the bolt holes could be bent down towards the head. You should tap this condition out with a hammer and dolly before reinstalling the covers. Check that the mounting surfaces are straight also.
Pugsy
76 C10 LWB
TPI 350

Offline VileZambonie

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Re: Changing Valve cover gaskets??
« Reply #9 on: October 14, 2007, 08:02:24 pm »
Go to autozone and get a cheap set of chrome ones with load spreaders for $40 bucks.
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