Help with leakdown/compression results
#1
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Help with leakdown/compression results
I'm looking at buying an evo x and this one I'm looking at seems nice felt fine, nothing notable, have dyno sheets from the same time this test was done will post both results. Was told it's fine but seems very suspect. 71k miles on it. Test was done at about 6000ft altitude here in CO. I'm hoping the altitude has something to do with it.
#2
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That motor is getting tired, leakdown is up there.
#3
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Agreed. You should be seeing around 150psi with less than 10% variance between cylinders on a broken-in 4B11T. 5% leakdown would be normal as well.
Was the engine warmed up? That could cause some low readings....
"Standard value (at engine speed of 200 r/min): 1,090 kPa (158 psi)
Lower Limit (at engine speed of 200 r/min): Minimum 650 kPa (95 psi)"
Was the engine warmed up? That could cause some low readings....
"Standard value (at engine speed of 200 r/min): 1,090 kPa (158 psi)
Lower Limit (at engine speed of 200 r/min): Minimum 650 kPa (95 psi)"
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I'm not sure how it was done, that was given to me with the car. Im ar 6000 ft so atmospheric pressure is around below 12psi, which translates to about 20-25% reduction in read compression, which means these numbers translate to about 120-135psi so it's not as bad as it looks but I'd agree I think shes working her way out, but I hope I still have some time. Planning a build very soon. It's the leakdown that worries me at the moment. I dont see or notice any burned fluid or loss of fluids. I'm going to do a valve lash check to see if they need adjustment, potentially could help bring that leakdown down. Any other thoughts on how I could help? Besides retesting knowing it was done right?
#6
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that's actually pretty good minus leakdown, with the conversion calculated that puts you around 150-155psi at sea level
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Looks like I'm in for a rebuild/build now though. Glad I still have my truck and bike. Hoping I can get it rebuilt with a weekend or 4 days without pulling thr motor. Just have the head resurfaced and someone come hone it.
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#8
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Going by this post, you don't know how a leak down test works, or what acceptable readings are. Good thing your shop is clean though...
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