WKeene

Just got a compression test done on my 86na (149Kmiles). Didn't sound too good. Mechanic said I had about 10K to 15k left on the engine, sound accurate?

Here's the numbers, what do think?

Front Rotor:
1 9.4
2 9.4
3 9.5

Rear Rotor:
1 8.9
2 8.8
3 9.1

(At 250 Cranking RPM)

Should I sell it and move on to a newer model (Turbo?)

Other problems:

Cat finally unclogged but won't pass emissions.
Leaking oil cooler lines
No AC
Needs new paint (faded)

hypntyz7

Son of a bitch man, those are really good numbers. FSM spec callsfor 8.0 on each rotor, which is about 90psi. I would say 9.0 is closer to 110-115psi, though I dont have that conversion factor in front of me. Anything over 110psi, IMO, is pretty good. Compression numbers are by no means an absolute measure of the rotary engine's health, due to other factors like carbon buildup and coolant seal health which cant really be measured. But, I wouldnt worry about it for a while, myself.

darkwaveboi

those are phat rims hypntyz, what are they?

hypntyz7

18" ace spades in gunmetal with yoko parada tires.

rxspd

Hey hyp, your subdirectories on your webpage arent working, just letting you know, just in case you dident already.

WKeene

Still more questions:

I should have asked the mechanic what "units" these numbers were in, but they look like "kg/cm^2", comparing them to the workshop manual, page 30-2.

If this is the case the lower spec limit is 6.0 kg/cm^2 . So, I'm well above that lower limit. Also, the max difference between any two chambers is spec'd at 1.5 kg/cm^2

So, taking the difference between my max and min (9.5 - 8.8) = 0.7kg/cm^2, I'm still in the spec limits.

I don't get why the mechanic would tell me that the engine is short lived.....

This looks good to me.

What does a brand new engine measure in kg/cm^2 ? Does anybody have these numbers?

rx-7fc

wkeene where did you get the compression test at and how much

von

Understand this. Once you warm up the car and get it starting the compression goes up 5-10psi. I believe your engine has lots of life in it. Just remember to do your maintanace stuff and dont rev to low for to long. (weeks). I noticed my idle smoothed out a bit when i got the confidence to rev my car to 5 during normal shifting. Idealy I would think 4.5 is good enougf. But I used to always shift at 3 wich is not good. Remember that.

WKeene

Had the compression done at Mr Mazda in San Jose. Not sure if it was 1/2 hr or 1hr of labor (45-90 bucks).

Thanks Von. I've had clogged cats and was having problems getting up to 5K earlier. Have unclogged them...now shifting at higher rpm (5K). Wow, didn't know how important that really was.

Hypntyz7, thanks for inputs!