yamaha 225 four stroke - compression

[kobidog]

looking at buying a 2000 pursuit 3070 powered with twin 2004 Yamaha 225hp four strokes.

i'm new to the whole 4s engines.

I had the marina send a guy (@ $200/engine) to test them:


PORT MOTOR STBD MOTOR
CYL #1= 175PSI CYL#1=175PSI
CYL #3= 175PSI CYL#3=175PSI
CYL #5= 175PSI CYL#5=175PSI
CYL #2= 165PSI CYL#2=150PSI
CYL #4= 165PSI CYL#4=150PSI
CYL #6= 165PSI CYL#6=150PSI

"THEY JUST CHANGED OIL IN MOTOR SO I COULDNT
SEE IF ANY DEBREE SO IF U WANT WE COULD GET A OIL SAMPLE
AND SEE IF THEIR IS ANY WEAR BUT BEST KNOWLEDGE COMPRESSION DIFF.
MIGHT NEED VALVE JOB . I HAVE SEEN THEM WITH 35OR 50 PSI DIFFERENCE AND
STILL GOING . IF YOU HAVE ANY QUESTIONS FEEL FREE TO CALL .THANKS"


I have asked him to do a leak down test but is it worth it?

they have 750hrs on each.

I think I'm going to send someone else there? and words of advice would be appreciated.

Thanks,

Colin

[kobidog]

a leak down was done on the Sb engine and he gave me these #'s:


CYL#1 0%
CYL#2 2%
CYL#3 12%
CYL#4 10%
CYL#5 3%
CYL#6 7%

vs his previous compression #'s of:


STBD MOTOR
CYL#1=175PSI
CYL#3=175PSI
CYL#5=175PSI
CYL#2=150PSI
CYL#4=150PSI
CYL#6=150PSI

does this sound right?

[99yam40]

I wonder if he told you where the leak by was coming out of on any of them( crankcase, intake, or exhaust) as that gives some idea of what the problem would indicate.
I am not an expert on any 4stk, but these #s do not look right to me.
The % and PSI on cylinder #s do not jive in my thoughts and I did not think 0% leak down was possible, but what do I know I have never checked one myself and do not know what is normal.

You need to find and expert
Check PM