Quick engine out of car compression testing question.
10-25-10, 06:19 PM
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Quick engine out of car compression testing question.
I was searching the forum and read something about being able to hand crank the engine and feeling a strong "puff" of air.
I figure its something like the cheap compression test with the engine in the car.
But I was just wondering if its supposed to be a puff like it is when you crank the engine in the car?
I hand cranked the engine a few minutes I go and can feel air, but it isn't a lot.
I just bought a streetported rebuilt engine off of someone on the forum/craigslist, supposedly 95+psi and around 30k miles.
Won't have my fc here for another two weeks and its killing me not knowing if the engine is good or not....
I'm sure it is, but.... lol.
Btw, I looked at the pineapple racing tool and it is 65 dollars. A little too much for a one time use.
I figure its something like the cheap compression test with the engine in the car.
But I was just wondering if its supposed to be a puff like it is when you crank the engine in the car?
I hand cranked the engine a few minutes I go and can feel air, but it isn't a lot.
I just bought a streetported rebuilt engine off of someone on the forum/craigslist, supposedly 95+psi and around 30k miles.
Won't have my fc here for another two weeks and its killing me not knowing if the engine is good or not....
I'm sure it is, but.... lol.
Btw, I looked at the pineapple racing tool and it is 65 dollars. A little too much for a one time use.
10-25-10, 07:11 PM
#2
Rent/Get a compression tester at your local auto parts store.
http://www.autozone.com/autozone/acc...er=487835_0_0_
$29.99.
http://www.autozone.com/autozone/acc...er=487835_0_0_
$29.99.
10-25-10, 07:47 PM
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Bolt the trans and starter on the engine.
Put 12 volts directly to the starter and it will roll over.
You can get some numbers off the comp tester from that.
Make sure that your Throttle body is wide open when you test it.
Put 12 volts directly to the starter and it will roll over.
You can get some numbers off the comp tester from that.
Make sure that your Throttle body is wide open when you test it.
10-25-10, 08:52 PM
#5
Poor mans compression test:
Turn engine over by hand. You NEED to hear 3 even puffs for each rotor. You will know when one face is missing compression since it will be like: puff puff.............puff puff.......puff puff instead of: puff puff puff puff puff puff puff puff. The sound is very distinct since you will be cranking and when you expect the puff, the puff is missing : )
Check both rotors.
Turn engine over by hand. You NEED to hear 3 even puffs for each rotor. You will know when one face is missing compression since it will be like: puff puff.............puff puff.......puff puff instead of: puff puff puff puff puff puff puff puff. The sound is very distinct since you will be cranking and when you expect the puff, the puff is missing : )
Check both rotors.
10-25-10, 10:47 PM
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Poor mans compression test:
Turn engine over by hand. You NEED to hear 3 even puffs for each rotor. You will know when one face is missing compression since it will be like: puff puff.............puff puff.......puff puff instead of: puff puff puff puff puff puff puff puff. The sound is very distinct since you will be cranking and when you expect the puff, the puff is missing : )
Check both rotors.
Turn engine over by hand. You NEED to hear 3 even puffs for each rotor. You will know when one face is missing compression since it will be like: puff puff.............puff puff.......puff puff instead of: puff puff puff puff puff puff puff puff. The sound is very distinct since you will be cranking and when you expect the puff, the puff is missing : )
Check both rotors.
3 puffs on each tell you your seals are intact,but that is about it.
go to www.rotaryresurrection.com and make your way to TECH,sec gen ..
it has some info on Compression testing.
10-25-10, 11:45 PM
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Gentlemen -- Have you honestly done compression tests this way? I don't mean to flame anyone ... however really... Unless you have a Mazda compression tester there is really no way to test compression correctly and rely on it.
Sure - you can remove the valve from a standard compression tester. . . You better have some pretty fast eyes or good ears- I have been around rotarys long enough to know this isn't a good measure. Ok - So you pull the trailing plugs out and listen for the 3 puffs ... Wait - Was that a puff from the front or rear rotor? Ill put a plug back in so we can only hear one set ... Then your not accurtatly measuring compression.
Sorry to burst your bubble slitherz90gxl - Wait on your car - Its the only real way to know for sure. As someone said - suppose you did hear all the puffs ... I have had blown engines make compression ... just not good compression.
Sure - you can remove the valve from a standard compression tester. . . You better have some pretty fast eyes or good ears- I have been around rotarys long enough to know this isn't a good measure. Ok - So you pull the trailing plugs out and listen for the 3 puffs ... Wait - Was that a puff from the front or rear rotor? Ill put a plug back in so we can only hear one set ... Then your not accurtatly measuring compression.
Sorry to burst your bubble slitherz90gxl - Wait on your car - Its the only real way to know for sure. As someone said - suppose you did hear all the puffs ... I have had blown engines make compression ... just not good compression.
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