Are these compression test #'s good or bad?

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Jun 27, 2005
1976 FJ55 compression test in psi:
cyl # 6 5 4 3 2 1
149 150 135 135 141 143

# 1 is near the radiator

Please let me know your thoughts on these numbers.


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way better than mine was!

i had a 160 average

what type engine. stock 2f?

#4 is not a happy little cylinder.

I always thought that you did not want a 10% variation from your highest to your lowest reading.

#4 is a problem. The rest are killer!
I am not sure I would trust the compression gage unless you have independent confirmation that the gage is working properly. Was the engine rebuilt and the head shaved? If the gage is 20% off, the numbers will be more like 160 on the high cylinders and 100 in number 4 (which is more believable to me).

I would bet that this thing has or has had a leaky brake booster and burned the number 4 valves as a result of leaning out the fuel/air mixture on this set of intake runners. BTDT

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