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Old 07-26-2014, 07:17 PM   #1
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Default Replacing head gasket...Shave head?

i am going to be pulling the engine and transmission out to a heap of maintenance stuff like cambelt,gerabox bearings, engine mounts etc and was thinking i should replace the head gasket too while its on the bench. the gasket itself is fine with no issues but i figure a 25 year old head gasket has a limited life.

Do i need to get the head shaved when replacing the gasket or is it just a matter of pulling head and cleaning the surfaces and refitting new gasket??

while the head is off i may do valve stem seals and clean my lifetrs too..(boy is this job escalating.)
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Old 07-26-2014, 09:00 PM   #2
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I would not reuse a head gasket regardless of mileage. I'm sure some do and get away with it but not worth the risk IMHO. So you are on the right track there.

If you have it off I would bring it to the machine shop. They can surface it without removing the valves (so cheaper). Multilayer steel gaskets need flat surfaces so I would always at least have it checked.

While it is at the machine shop and if you plan on replacing valve stem seals (recomend), have them check the valves for sealing. This way you can have them "bump the seats" if needed and replace the seals at the same time.

I'm just saying, if you have it off, why not? It won't hurt anything but your wallet and just a little. I don't think I paid $200 for all of this last time IIRC. I only planed on seals and surfacing but had them check the valves and they were leaking "a little more than he'd like to see".

You can check for leakage yourself too. After you have it cleaned up, pour some rubbing alcohol in the combustion chambers. How fast does it leak out? After machining mine looked like the same amount of alcohol after 5 minutes so I was satisfied.
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Old 07-26-2014, 11:55 PM   #3
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oh i wasnt gonna reuse the gasket. just explaining that i wasnt replacing the HG because it had blown or something.
just wonderin if you have to machine the head before refitting or just clean up the surfaces??

any good gaskets> prob just use a felpro. dont wanna have to machine to fit a MLS one
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Old 07-27-2014, 12:12 AM   #4
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Stock gasket is mls.
So yes, I'd surface. Or at least checked it for flatness.
I don't know about felpro.
Now, read above so you can take adavtage of the machine shop while you are there.
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Old 07-27-2014, 12:12 AM   #5
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Don't know why double post.
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Old 07-27-2014, 02:22 AM   #6
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OEM HG on a '90 is composite, not MLS. You can replace a composite HG with just a cleanup and checking the surfaces for flatness. The composite gasket will do OK on a street-driven turbo car. It won't hack it if you track the car. Recommend ARP studs and MLS gasket for track.
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Old 07-27-2014, 03:03 AM   #7
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its just a street car for the time being. plans are to track it at a later date but i'll do a full rebuild before i do that. (or just let it die and buy a long nose motor when it does)

i'll just throw in another composite gasket in. Felpro is composite?
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Old 07-27-2014, 03:07 PM   #8
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Quote:
Originally Posted by 4sfed5 View Post
its just a street car for the time being. plans are to track it at a later date but i'll do a full rebuild before i do that. (or just let it die and buy a 1.8 when it does)

i'll just throw in another composite gasket in. Felpro is composite?
FTFY.

Felpro replacement for 1.6 is composite.
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