Cylinder compression?
#2
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The last compression test I did on mine was around 145psi per cylinder, which is considered to be in good health from what I have read. I also helped test another 951 engine about a month ago which did around 140-145psi per cylinder.
#3
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In general i think the most important thing is that they're all within ~5-10% of each other. Sounds like your motor might be a little more worn than some, but if it's not burning a ton of oil it's no big deal. Things like altitude affect the readings so i wouldn't say "if it's not ____ it's a problem".
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I've been rebuilding my engine. Compression was 125 all over the board... eating oil like crazy (I'm DE'ing it though).
140 + is an engine in good shape.
c.
140 + is an engine in good shape.
c.
#5
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My engine was ~130 across the board before it blew a HG @ 90k and it was the same after the rebuild (after ~1k mile break-in). I never tried another compression gauge or used this one on a different engine, so I am assuming the gauge is a little off -- but who knows.
So long as it is even across the cylinders, you are in good shape IMO.
The typical "acceptable" range is 140-150 hot, with the throttle wide open.
So long as it is even across the cylinders, you are in good shape IMO.
The typical "acceptable" range is 140-150 hot, with the throttle wide open.
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The compression ratio on the 951 in reality ranges from 7.5:1 to 8.5:1 so the numbers vary from
engine to engine, healthy or not. If you're above 125, and similar across the board, unless you have
a good reason to rebuild, just drive it.
engine to engine, healthy or not. If you're above 125, and similar across the board, unless you have
a good reason to rebuild, just drive it.
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