Conflicting Compression Check Numbers

[pursuit1]

I've got a Suzuki DT 140 that idles very erratically, and rev's fall off at 4800 rpm. Did compression check, with all four cylinders ranging from 120-130 lbs. Just got a call from dealer who looked at it over the weekend & tells me my motor's spent i.e. technically blown from a compression stand point. Granted, I used a "push in" type compression gauge, but my readings were consistent and within 10% of each other. How could my numbers have been so far off?

 

[Hooty]

Re: Conflicting Compression Check Numbers

I 'd bring it home and test again, show the results to the dealer that said your engine was "technically blown" and find another shop.<br /><br />c/6<br /><br />Hooty

 

[cotterman]

Re: Conflicting Compression Check Numbers

i agree with hooty<br />let the dealer prove to you by showing his compression tests.<br />without compression as he states your motor probably wouldn't even start<br />get a second opinion

 

[ledgefinder]

Re: Conflicting Compression Check Numbers

Sounds like your compression's OK - pretty hard to get good numbers by accident. You can double-check with another gauge I suppose. You took the reading 'dry' without squirting any oil in the cylinder, right?<br /><br />Your dealer may have not gotten a good seal on the gauge on one or more cylinders. Good thing you found out.

 

[jim dozier]

Re: Conflicting Compression Check Numbers

Test it at home again with the engine warmed up, plugs out, full throttle, and use a screw in type tester they are the way to go and aren't that expensive. Then you'll know for sure. My guess is it OK and your dealer isn't.