Daniel K

Hi everybody,

my engine works fine, I only recognized (maybe once a month) that the sound changes a little bit (above 100mph) - but only when it's really hot outside (this sound appears and goes away for more than 3 years now!).

So I went to my dealer today and asked him to check the compression, result:
12,8 10,4
12,8 14,5
14,9 12,5
(results in bar)
for reference, regular compression is around 6,9-8,5bar.

Can anybody imagine what this means in detail - maybe someone here with an similar problem?

Thank you very much for your help (I'm really lost at the moment :-( )

nycgps

iTrader: (1)

some seals are stuck.

dannobre

iTrader: (3)

I would question that the tester is working correctly.....

Also why are the results in 3 rows? Should be 2 rows of three entries to make sense with an RPM reference for each row??

Daniel K

Hi there,

3 rows due to 3 "areas" from each rotor.... all measured with Starter RPM

"Tester?" That was my first question at my dealer (they measured some other RX8 with this test equip as well - without any trouble - I think if there would be something wrong, the test results must be lower, not higher?)

@nycgps: What seals exactly do you mean, any clue? Is there a chance to clean the engine?

THANKS!!!!!

Brettus

iTrader: (2)

Possibly you have a boat load of carbon in your combustion chambers ?
Do you redline often ?

Daniel K

Yep, I love my redline (minimum two times a day ;-) )
So normally no reason for carbon...?

WHAT IF I JUST CONTINUE RUNNING THE ENGINE? (so far 60000 miles reached)
Will this pressure (compresion = more than 210 PSI within the engine) destroy the engine????

TeamRX8

iTrader: (25)

maybe in your brain since it apparently has severe compression loss






looks like they're using kgf/cm*2 units (note that 10.2 kgf/cm*2 = 145 psig), what was the cranking RPM?



.

nycgps

iTrader: (1)

blah

arghx7

Take your life.

Daniel K

Cranking speed was 290rpm....
so thats still 210 psi (my bloody measurement) against 130 psi (acc. your table)... :-) :-( ???

dannobre

iTrader: (3)

Sticky seals will not raise compression...either the tester was wrong, or there is a horrid buildup of carbon on your rotor faces causing the tubs to be way smaller...this is unlikely because with that much carbon there would be seal issues as well......

Oh...did I say that the tester is likely wrong

Or you have a great motor and have nothing to worry about....

Or you have a blockoff plate on your exhaust

nycgps

iTrader: (1)

people cant get joke these days ...

Razz1

Well... with an alarm going off all the time with flashing lights...........