compression tests!!!!
07-31-02, 12:07 AM
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compression tests!!!!
ok ummmm can bad spark plugs/wires, bad battery (causing slow cranking) cause low compression tests?
my mechanic said even motor oil level can cause different compression levels.
my mechanic said even motor oil level can cause different compression levels.
07-31-02, 01:19 AM
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You might want to get a new mechanic...
Spark plugs and wires can't affect a compression test. I think it could if he takes out both the leading and trailing plugs on the same chamber though.
Oil level can't really affect compression test. But it oculd if the car wasn't warmed up and the oil hasn't lubricated the motor.
Heres the low down on compression. You want at least 6.0KG or is it 85psi per chamber and want it uniform for every chamber..as well as per rotor.
Make sure the motor is warm/opperating temp. Make sure that you depress the throttle.
Danny
Spark plugs and wires can't affect a compression test. I think it could if he takes out both the leading and trailing plugs on the same chamber though.
Oil level can't really affect compression test. But it oculd if the car wasn't warmed up and the oil hasn't lubricated the motor.
Heres the low down on compression. You want at least 6.0KG or is it 85psi per chamber and want it uniform for every chamber..as well as per rotor.
Make sure the motor is warm/opperating temp. Make sure that you depress the throttle.
Danny
07-31-02, 02:05 AM
#3
I dont see how bad wires and plugs can cause the compression to be low, a bad battery or a bad starter that doenst doesnt crank like normal will cause a lower compression reading. Compression varies from temperature and cranking speed, theres a chart in the manual. If you car was so low on oil that you bearings are not being lubed and that it was causing enough friction to actually slow the rotors from turning, then yes it will cause a lower reading. But if that were the case your engine would be toast soon anyways.
08-01-02, 01:19 AM
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all he said was it may be due to the slow cranking on the starter or battery.
the spark plugs and wires were my stupid questions. hehe.
he also told me that since my motor only has around 7000km its not fully broken in and the compression could still go up. is that right guys? this mechanic is like the best in town. everyone says hes the best in town.
the spark plugs and wires were my stupid questions. hehe.
he also told me that since my motor only has around 7000km its not fully broken in and the compression could still go up. is that right guys? this mechanic is like the best in town. everyone says hes the best in town.
08-01-02, 01:44 AM
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7000km? KM stands for kilometers. He probally means 7.0KG/cm2.
That would be a pretty good compression.
You need to make sure the motor spins at least 250rpm. If the battery or starter is weak, you wont' get that speed. ANd yes, compression should rise as you break in your motor.
Danny
That would be a pretty good compression.
You need to make sure the motor spins at least 250rpm. If the battery or starter is weak, you wont' get that speed. ANd yes, compression should rise as you break in your motor.
Danny
08-01-02, 08:08 AM
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Originally posted by RX7Elmo
7000km? KM stands for kilometers. He probally means 7.0KG/cm2.
That would be a pretty good compression.
You need to make sure the motor spins at least 250rpm. If the battery or starter is weak, you wont' get that speed. ANd yes, compression should rise as you break in your motor.
Danny
7000km? KM stands for kilometers. He probally means 7.0KG/cm2.
That would be a pretty good compression.
You need to make sure the motor spins at least 250rpm. If the battery or starter is weak, you wont' get that speed. ANd yes, compression should rise as you break in your motor.
Danny
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08-01-02, 01:59 PM
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i just replaced the starter tho. maybe i need a new battery for the slow cranking. after i relocate the battery and break it in alittle more i will do another compression test again. thanks guys.
one more question. if the compression is low due to slow cranking. how much will it be off by? 1.0kg/cm^2?
what i mean is; is the difference signifigant?
one more question. if the compression is low due to slow cranking. how much will it be off by? 1.0kg/cm^2?
what i mean is; is the difference signifigant?
08-01-02, 02:32 PM
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Originally posted by Freaky Monkey007
Why exactly do you need a rotary compression tester??
Why exactly do you need a rotary compression tester??
08-01-02, 10:24 PM
#14
Blow up or win
Originally posted by 3rdGen7
Where can I buy a rotary compression testing unit ??
Where can I buy a rotary compression testing unit ??
Better yet, borrow one.
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