I bought a 1980 Mazda RX7 that lost power so I took it to a mechanic. The diagnostic showed compression check at 120 PSI.. Also needed a new carb. After installing new carb, replacing spark plugs twice (because they kept getting flooded), putting in new gas twice (first time because gas was old and second time because 2 qts of oil ended up in gas tank) the engine still looses power. Mechanic says I need a new engine because rotor tips lost ability to seal...compression check at 65 - 100 psi. Should this be on me or is of it be the mechanic.

 

compression won't go from 120 down to 65 unless something happens.
chambers are probably washed out from all the flooding.

change your oil and plugs again. crank the motor for 10-15 seconds with the plugs out to blow all that **** out, dump just a little bit of atf down the carb (then clean it out once you get it fired up).

has the carb been tuned?

 

Thanks for the advice. I ended up getting a rebuilt engine and a rebuilt carb. It's a great car now. Runs like it was meant to. My daughter has it at college so now she can be mobile with an awesome car.