compression test went badly
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compression test went badly
well i just did a comp test and got 50psi per rotor, im pretty sure thats a fail, or is there anything that could cause a false reading, im pretty sure my intake mani is leaking but im waiting on the new gaskets to come in
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the car had just shut off, battery was good, i held in the pressure release on the guage cause my roomie wouldnt let me take the shrader valve out, and both rotors bounced to 50psi max, with litte variation on the two, and im not sure if the engine has ever been rebuilt or not
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yea i thought something was up with the reading cause there should be some sort of fluctuation if the psi is that low. and when i say bounced i mean every time a rotor face would make compression it would move the needle up until the face was no longer making compression and it was released out of the gauge.
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#8
Sharp Claws
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well what you are doing by holding down the release is allowing some air to bypass before getting to the gauge at all, skewing your readings lower than they actually are.
by removing the schrader valve in the hose to the gauge it allows the pressure to go to the gauge and peak the needle and dump the air back into the housing once past peak. this will give you an accurate pressure test reading for each rotor face.
by removing the schrader valve in the hose to the gauge it allows the pressure to go to the gauge and peak the needle and dump the air back into the housing once past peak. this will give you an accurate pressure test reading for each rotor face.
#11
Rotary Freak
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Before you do anything drastic, like rebuilding the engine, spend a few bucks and have a proper compression test done with a tester designed for rotary engines. You must normalize any numbers you get by using the charts in the factory service manual. In order to do that, you need a tester that will provide the engine rpm at the time of the test. Even though you think the "...battery was good.", it may be old and weak and not fully charged resulting in an engine rpm significantly less than the 250 rpm used by Mazda to specify acceptible compression.
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the battery is good, it was installed at the beginning of summer and was just tested at my college (im a auto student) after work tonight i am def going to dig deep into it and see what i can come up with, now im not getting spark from either coil like the cas went bad
#14
Holding down the valve will show you if you have a busted apex seal, because you'll get one bounce and 2 very little bounces.
If you want accurate compression readings for each chamber, you'll need something fancier as others have suggested.
If you want accurate compression readings for each chamber, you'll need something fancier as others have suggested.
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