understand compression test result?

[mmm]

Hi
I am at looking at buying a rx7 and the seller is telling me thta he has invoices to prove the following results:

front rotor: 8.0 - 7.9 - 7.8, rear rotor: 7.7 - 7.9 - 7.6     @250 rmp

any good?

[G@NDY]

They are very good results and show a healthy engine, HTH.

[mmm]

cheers mate, the rebuild was done 4 years ago by Re:Worx and has done 23,000 miles, does the result seems too good to be true?

[G@NDY]

It seems reasonable, but a compression test isnt the holy grale to happy rotary ownership but its certainly a some high numbers and if the price is good and it doesnt use any water etc then go for it matey. When was the comp test done?

[gsb876]

Those are definately good results :Thumbsup!

[skybusr34]

as everyone has said. good compression results. think a brand new rotary is 8.5bar


rear rotor always reads slightly lower compression than the front 3.  .. but the water seals could still go. thats the gamble

[mmm]

Thank you for all the replies, I have looked at the car and test driven it I decided not to buy yet without further research.


The car has a few problems, 1st when you accelerate hard there is smoke from exhaust its not blue or grey and its only very little bit not allot the seller said to me that the car is decated. 2nd when you start the car is has a rough idle only till its worm then its ok and. 3rd there is a slight noise from the engine sounds like belts squeaking to me?


any advice much appreciated

[skybusr34]

white smoke could be water vapour. , did you do the champagne test.??

[mmm]

what is the champagne test? cause when i looked at the filler cap there was very small maynoise but not much, but there was no signs of water and oil mixture on the dip stick or water cap.

thank you for the reply

[skybusr34]

champagne test is a crude way of testing coolant system when engine is cold.  

when engine is cold, take off the main coolant cap .. start the engine. look into the coolant filler hole and look to see if you get champagne bubbles . if you do thats a sign compression is blowing past the coolant seals into the coolant.