New to me 86 GN

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1 RARE T

Master Mechanic
Jul 14, 2015
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I will say this clearly: If you bought a ScanMaster after 1999 you are a ****ing idiot sheep.
also the TR community was drying up or just plain full of cranky old farts and leftover shitty personalities.

Someone needs to go take a sh*t or something. 🤪
 

motorheadmike

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Nov 18, 2009
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kornball426

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May 29, 2009
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Just quick update, didn't get a chance to read the new posts and reply. Cooling system holds pressure just fine, 4 out of 6 cylinders are within one or two pounds of 160 psi. 1 cylinder reads 170 psi, and one right around 150... That's really not bad I don't think. Starting to think engine might be fairly healthy, I don't have a manual what should the compression be ideally?
 
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Sundancer

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Nov 1, 2015
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Much respect to everyone here who does what they like to there car, no matter what others think😂my 1985 Grand Prix LE stays totally stock with a constant emphasis on mechanical and her exterior - All original👍
 
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kornball426

Royal Smart Person
May 29, 2009
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Just quick update, didn't get a chance to read the new posts and reply. Cooling system holds pressure just fine, 4 out of 6 cylinders are within one or two pounds of 160 psi. 1 cylinder reads 170 psi, and one right around 150... That's really not bad I don't think. Starting to think engine might be fairly healthy, I don't have a manual what should the compression be ideally?

Anyone got an opinion on whether those numbers are okay, should I be worried?
 

kornball426

Royal Smart Person
May 29, 2009
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The 150 is a little low, but the 170 is good.

Yeah 150 worried me more than any of the others, now that said I did the test on a cold engine that's been sitting for at least a month. Compression may be better on a warm engine, and who knows if I'm getting good ring seal...

Also did a coolant pressure test, pumped it up to 16 psi and it held that pressure for like 15 minutes before I was satisfied there's no significant leaks and released the pressure.
 
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motorheadmike

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Nov 18, 2009
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The compression variance is fine. My old Buick was about the same and I constantly ran that thing hard. If you didn't hear air leaking past the valves or rings all should be well enough.
 
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kornball426

Royal Smart Person
May 29, 2009
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The compression variance is fine. My old Buick was about the same and I constantly ran that thing hard. If you didn't hear air leaking past the valves or rings all should be well enough.
I didn't do a leak down test, so I couldn't hear anything... Just cranking it for few seconds till the gauge didn't go any higher. Reset, move to the next cylinder, repeat.
 
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