Old #7 got me!
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Joined: Aug 2007
Posts: 83
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From: Cambridge Ohio
Old #7 got me!
I started getting the 87 ready for valve guide seals, still running good at 213,000, just a bit of smoke at start up. Ran a comp. test and all 8 was at 175-185 psi., I thought I was good to go. Then I pulled all the rocker arms and put 100 psi in #7 with the rad. cap off, level rose 1" in about 30 sec. I was already planning on 1.6 roller rockers and lt4 springs, was wondering if there is a preferred head gasket brand that is superior to others? I will most likely have the heads machined unless they are super flat, what is the most that can be taken off with no intake alignment issues? I suspected #7 as my low coolant light started coming on at the end of the season, but my level looked good when checked, was burped and light gave me no problems all season. Any input would be appreciated.
Suckin' gas, haulin' ass.
Joined: Apr 2010
Posts: 1,100
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From: Newport News Virginia
I started getting the 87 ready for valve guide seals, still running good at 213,000, just a bit of smoke at start up. Ran a comp. test and all 8 was at 175-185 psi., I thought I was good to go. Then I pulled all the rocker arms and put 100 psi in #7 with the rad. cap off, level rose 1" in about 30 sec. I was already planning on 1.6 roller rockers and lt4 springs, was wondering if there is a preferred head gasket brand that is superior to others? I will most likely have the heads machined unless they are super flat, what is the most that can be taken off with no intake alignment issues? I suspected #7 as my low coolant light started coming on at the end of the season, but my level looked good when checked, was burped and light gave me no problems all season. Any input would be appreciated.
I'm running the Fel-Pro gaskets. I also went down 0.010" on the heads and had no issues with the intake. Don't forget new head bolts/studs.
Le Mans Master
Joined: Mar 2004
Posts: 5,107
Likes: 171
From: Dublin CA
As long as you did not over heat the engine, the heads are probably good. Just replace the gaskets. The problem is actually two fold. 1) Aluminum heads expand and contract at a different rate than the cast iron block, so the gasket will eventually give out. 2) Even the Fel-Pro gaskets have to match the water passages in the block and head. Numbers 7 and 8 cylinders have a passage that is only about 1/8" from the cylinder. When you pull the heads, I am sure that is what you will find.
Since you have the heads off anyway, may as well have a valve job done. Since the machine shop has to pull the valves, if you provide the new springs they can swap them out. They will also have to install new seals. I would suggest that you use intake seals for both the intake and exhaust.
Since you have the heads off anyway, may as well have a valve job done. Since the machine shop has to pull the valves, if you provide the new springs they can swap them out. They will also have to install new seals. I would suggest that you use intake seals for both the intake and exhaust.
Instructor
Joined: Oct 2004
Posts: 208
Likes: 1
From: Santa Rosa CA
Just went through this on my ’89. Take some digital photos, really helps when putting it all back together. It takes a fair amount of time to do the job so consider having the heads surfaced and valves ground at the same time as a good investment. Ditto on the felpro. Make sure all the surfaces are real clean on assembly. I think all the bolts are reusable but thread chases are helpful when putting it together. 
Max G’s
Joined: Nov 2008
Posts: 2,751
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From: Monroe OH
NCM Sinkhole Donor
#7 got me too late last year in my stock 91 coupe. I went with OEM Gaskets on mine. Of course with this car I wasn't looking to boost increase comp ratio or anything. I'm keeping this car stock for now. 
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Joined: Aug 2007
Posts: 83
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From: Cambridge Ohio
I'm keeping mine mostly stock as well as I would like to do some road trips in this one. I scattered the stock rockers on the bench so I can look at the wife straight-faced when I tell her I have to buy new rocker arms!
Le Mans Master
Joined: Mar 2004
Posts: 5,107
Likes: 171
From: Dublin CA
I like that......
......really honey....these are all dirty and show wear. I MUST get new roller rockers, not doing so just might lead to one of the old ones breaking and destroying this good engine. 
I should try that one....but my wife has been around cars and engines for years and would NOT buy it!
......really honey....these are all dirty and show wear. I MUST get new roller rockers, not doing so just might lead to one of the old ones breaking and destroying this good engine. I should try that one....but my wife has been around cars and engines for years and would NOT buy it!