Hello my name's Lukasz and i need advice.
I want buy rx8 HP,and the salesman checked for me compression...
First rotor has a compression 75 psi 158rpm and the second 72 psi 157rpm
Please tell me this compression is ok or not.
i saw in manual that this compression is not bad but i'm not sure.

 

That doesn't sound like a valid compresaion test. You need 6 values. You can't use a regular compression tester, 2 faces o the rotor could have 0 compression and a regular tester will still show whatever the 3rd faces compression is. But if the starter only turns at 158rpm, you will at least need a new starter.

 

Yes,but there is one problem the car is in Germany and i live in Poland,and i must decided what to do now,he can bring the car for and i must pay...
And he checked compression with the normal notebook plug in obd and regular compression tester because he have only this.

 

Then your choice is to buy a car in unknown health, or to not buy a car in unknown health. Do the Mazda dealers in Germany have the right equipment to test the car?

 

yes they has,but the polish salesman is greedy and he dont want pay for this...:/
the car is beauty but the engine....
Thank you very much for your help
i must think about this

 

Sounds like I would pass on this one if the salesman is putting pressure on you like this. Better safe than sorry, sounds like he has something to hide. Trust your instincts. I would walk away.

 

+1^ Agree 100%
If you can not get a rotary specific compression test, (2 sets of 3 numbers for each of the 2 rotor's faces) then do not buy it.
If someone is not hiding something, then they would agree to at least split the cost with you.

 

Its not a real test but using a standard ( non rotary) comp tester you should get at least 120psi per rotor
I would say your engine is knackered needs rebuild
Was that value hot or cold?

 

Sinkas,

Simply put you are wrong.

In an above post you can see information given about non rotary compression testers.


You can't use them. Why? Because even if you have 0 compression on 2 of 3 rotor faces but one has 90, it will read 90. Also you can nor get an accurate RPM.

Have a nice night.

Travis

 

Better safe than Sorry!
if you can't get a proper compression then its safer to pass on it.
It's a gamble, who knows the car might be in perfect shape, but imagine if the engine indeed needs a rebuild it will be super costly.

Talk to the sales person and ask him if he will split the cost 50/50 to get a compression test from Mazda dealer.

All the best :-)

 

Hi,
No I am not "Wrong"
What I have suggested in certainly suboptimal,
but any sort of compression test is better than none,
particular in the absence of access to a " proper" test
notwithstanding that,
any engine that cranks up under 80psi on a Ghetto compression test is not likely to be a good proposition,
so to the OP's,
either buy a comp tester,
and pay from one or find another car