How to do a Compression Test on your motor

General engine questions/issues that aren't specific to the other categories
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By BAXTER_EJ1
- Wed Feb 13, 2008 1:12 pm #42115 Take it up with Haynes, not me... :eh:

By Bob Mknob
- Thu Feb 14, 2008 1:56 pm #42282 Sorry, I didn't mean to give the impression that I thought you came up with that winner of an idea. I was just attempting to impart an alternative and less messy solution to your concern. :thumb:
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By ChicagoMike
- Thu Feb 14, 2008 1:59 pm #42284 Hahahah, f*ckin taking a gas bath, that would suck having that spraying all over the engine bay!!
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By VegasCivic
- Sun May 11, 2008 5:54 am #54705
Greasedmonkey wrote:
stefan wrote:A cold engine doesn't seal as good as a warm engine.
Warm metal expands, a nice example is that military airplane the US has, it leaks like a drunk teenager when on the ground, but is perfectly closed when hot.

But nice write up Teal!! :woot:



Dont talk bad about our SR51 its a awesome jet. The blackbird rocks. I had the GI Joe toy too.


[smilie=BangHead.gif] ...its the sr71, not 51.
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By KRYSTED9354
- Sun May 11, 2008 4:15 pm #54731 I've done this a few times and teal everything ur doing is 100$ right, just u have to have 1 person looking at gauge , and 1 person florign the pedal and cranking it for 3-5 cranks , then thats your compression, so it take 2 people to do this no matter what.

By JDM_adam
- Fri Feb 05, 2010 3:03 pm #173441 Hey i just did a compression test and i got 210psi, 205psi, 203psi and 215psi. Is that good? :?

By JDM_adam
- Fri Feb 05, 2010 4:05 pm #173458 When I did it I thought it was like abnormally high :eh: Any reason for this?
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By Coplies
- Wed Dec 01, 2010 11:48 pm #225512 So I have the little d15b7 in my eg and got like 100 for all of them. How bad is this?
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By Coplies
- Thu Dec 02, 2010 12:59 am #225527 250,000. What can I do about it? I probably need new rings huh, it does burn some oil
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By teal_dx
- Thu Dec 02, 2010 3:26 am #225541 usually it is rings or valve seals. You did do the test with the engine warm, right? a cold motor will have lower #'s because heat expands the metal parts, making the tolerances tighter.
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By Coplies
- Thu Dec 02, 2010 9:59 pm #225685 It was warm :( I used the meter that you have to hold down by hand so that could have yielded lower numbers. If I need new rings I may as well just swap huh?
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By Ajax1989
- Wed Mar 09, 2011 10:52 pm #243218 i got these

cyl#1-100
cyl#2-90
cyl#3-100
cyl#4-115

is that good, and im buring oil too
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