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Low compression
I was cleaning my spark plugs today and decided to check the compression. Its 75 rear rotor and 77 on the front rotor.
Just wondering should I take this down to the dealer ship and see if I can get the engine warrantied or does it need to be lower then that? Also how much would they bitch if I wanted them to put in a new clutch I bought while they are putting in a new engine? 64000 miles 2005. |
From what I understand, you need a special tool to measure compression on a rotary engine. Also, a proper compression measurement for a rotary would have 3 numbers per rotor plus a the rpm at which the measurement was taken.
I would search the board for compression threads to learn more. |
I under stand if I wanted to check each number indavidually I need a special tool. But it should still give me the maximum PSI from all 3 (which is 75PSI and 77PSI).
Am I wrong? |
From what I understand from the compression threads I've read, yes that is wrong.
You need the 6 measurements (one for each face on the two rotors, 2 x 3 = 6) and the rpm at which the measurement was taken to tell if the engine will qualify for replacement. |
Ok I barrowed a buddys that he used on his RX7, I am getting roughly 75-80 on all 6. Nothing dropping so I am assuming the apex seals are ok.
But I thought spec was 98-120 75-80 seems very low. |
This thread has some of the information I'm talking about:
https://www.rx8club.com/series-i-tech-garage-22/do-we-have-diy-compression-test-138892/ |
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You need something like this to TEST YOUR ENGINE PROPERLY :)
https://www.rx8club.com/attachment.p...1&d=1338172001 I mean a piston compression tool works too, but sometimes you really gonna have a hard tell to "tell" which face has less compression. |
I think the compression is "good" on each face, but the overall compression is around 75 is this normal?
I have seen videos of this engine running at 100+ PSI and the rating from Mazda says 98-120 PSI. I am sure all the faces are pretty good I am more concerned about the 75PSI right now. |
How and where did you get that Mazda compression tester nycgps? Can you buy that outside besides the Mazda dealerships? Just curious.
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