jaydogg

thinking about buying another 3rd gen and the guy said he had a compression test done and the scores ranged anywhere from 5.0 to 5.5 how much life does it have left? thanks

Want2race

Hmm Its got life, Its just not going to be too fuel efficient and run very strong...

I would say you could drive around till they are around 4 bar... Thats when you NEED a rebuild.. Until then you just need to be aware of you WILL need one soon

RonKMiller

You really need to find a rotary tech with a Mazda brand compression tester to get an accurate view of the engine. It can be done with a standard dial gauge but it is only a VERY rough estimate since you need to read the dial as it "blips". I would not depend on the seller to tell you what the compression is.........ask him how it was measured and you'll know if he has a clue what it really is or if he is bullshitting!
There are two types of Mazda testers and they both work quite well. The older style looks like a polygraph and is really accurate, the newer one is digital and is ok but does not provide the cool looking tracings so you can see the rotors as a black and white graph though the entire cycle! They each cost about $3500 if you can find them, and the old ones are collectable and very rare since they are so "analogue".
I would not even THINK of buying a used 3rd gen without an accurate compression test!

1FAST7

5.3 is a little low. 6.0 is the minimum recommended. Im not sure about how much life is left. btw, how many miles are on your engine? something that could have affected the test, is if the car was cold.

try testing it again.

1FAST7

rynberg

Also, the throttle needs to be open during the test. If the throttle is closed, you will get 5s and maybe very low 6s.