Is it possible for a non rotary specific compression test to return results of 120+ psi for both rotars and the engine still be blown?

This is what my mechanic is telling me. Repeated compression tests (not using a rotary compression tester) have shown good compression. But the motor will not run and he's telling me his gut is saying the motor is ruined. It's a Mazda reman with 40,000km.

TY

 

no.

 

i wonder if he didnt hold down the bleed valve and he was getting 120+ psi total on each rotor and not 120-120-120 pulses.

 

^ yeah, if the bleed valve is not open, you will only see the highest compression number. Then when the other chambers come around, if they are lower compression, they won't boost the needle any higher, but the valve won't bleed off the pressure to show you what the next chamber is reading.

 

maybe it could be a water/oil seal .....

 

i've got 110 psi on a rotor with a broken apex seal...the one side held fine.

you have to watch the tester for even pulses, instead of just the total number.