Compression numbers on a 2002 Optimax 225

[vabass]

Considering buying this boat and had the engine tested at a dealer and this is what it showed.
(Contrary to what many have said before, I believe the test was done on a cold engine)

#1 - 95
#2 - 98
#3 - 98
#4 - 102
#5 - 90
#6 - 100

Book calls for compression to be between 90-115, with a 15% variance.

Would you be comfortable with these numbers, especially that #5 cylinder?

[grout-scout]

You will get a “it needs to be warm” response.

[vabass]

True, I expect that, but in talking with a couple of mercury mechanics, they both said the engine didn't need to be warmed up for the test. ??????

[hstechfl]

If you really want to be sure have them do a leak down test. That should remove any doubt.

[Savage]

True, I expect that, but in talking with a couple of mercury mechanics, they both said the engine didn't need to be warmed up for the test. ??????

The guys you talked to are wrong.......

Follow this procedure EXACTLY as stated.......

Click on this>>>>> Performing Compression Tests

Then tell us the numbers.

[vabass]

Thanks.


Savage, I tried to send you a PM, but you have too many and the system won't allow you to accept any until some are cleared.

[EuropeanAM]

Might re-check the book, it does NOT permit a 15% variance.

90-110 psi, max variance is 15 PSI.