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  1. #1

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    cylinder compression off

    Hey everyone,
    I posted that I lost about 300 rpm, 8100 down to 7800 rpm not to long ago. It was suggested that I check the oil level to make sure it wasn't overfilled . It seemed to be okay so I took it back to the shop. They check out the supercharger clutch that check okay. Then they did a compression test: 120psi 120psi 140psi
    That seemed to be a little off, anyone have any idea what would cause this problem?
    Thanks,
    Dave


  2. #2
    Site Admin Green Hulk's Avatar
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    Was the compression test done on a hot engine?

  3. #3

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    Your valves are probably leaking. Do a leak down test on a hot motor. My local machine shop charged $125 for a 3 angle valve job.

  4. #4

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    Hey Guys,
    I'll have to find out if was done hot or cold. Wouldn't you think though that they would be the same cold or is the motor that loose to cause such a big difference. Will the aftermarket warranty take care of something like that?

    Dave

    05 RXT riva stage 1 kit

  5. #5
    Site Admin Green Hulk's Avatar
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    Compression tests must be performed with a hot engine to yield accurate results.

  6. #6
    Site Admin Green Hulk's Avatar
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    Quote Originally Posted by DandSPro View Post
    anyone have any idea what would cause this problem?
    Thanks,
    Dave

    More than likely its just a worn wear ring.

  7. #7
    Got Boost? psycho rxp's Avatar
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    Quote Originally Posted by DandSPro View Post
    Hey Guys,
    I'll have to find out if was done hot or cold. Wouldn't you think though that they would be the same cold or is the motor that loose to cause such a big difference. Will the aftermarket warranty take care of something like that?

    Dave

    05 RXT riva stage 1 kit
    Like stan said it's probably your valves leaking. And yes, warranty should cover it. Are you experiencing any coolant loss?, or overheating?

  8. #8
    Moderator The Bandit's Avatar
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    Psycho,
    you may have already mentioned it, What ended up being the problem with yours?(the coolant loss)

  9. #9

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    Hey everyone,
    No coolant loss or overheating . The water conditions was fairly calm, temps of the water 68 degrees and the air was at 60 degrees. It also seemed that the midrange acceleration was kind of lackluster (3500 rpm to 7500 rpms)

    Dave

  10. #10
    Got Boost? psycho rxp's Avatar
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    Quote Originally Posted by RXP Steve View Post
    Psycho,
    you may have already mentioned it, What ended up being the problem with yours?(the coolant loss)

    My valves were leaking, and the head gasket was starting to go. I got a new coolnt bottle (was warped & cap wouldn't seal) New ride plate (leaking) exhaust valves, head, and gasket Runs great now. I can hold it wide open, and no more overheating.

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