Low compression?

[Fonz]

I have a 2002 Sea-Doo utopia 185 with the Merc M2 210 hp. I’ve owned it for three years.
350 hours
I have always had trouble getting it started from a cold start but once it runs it runs very well. 50 mile an hour plus
I am checking out fuel system and ignition system including spark.
Just did a compression test and did not like the readings. I like the consistency but not the compression. How bad is it?

Sea-Doo compression
87 top Starbord
90 Centre starboard
85 bottom starboard
85 top port
87 middle port
90 bottom port

 

[Tim75]

I have a 2002 Sea-Doo utopia 185 with the Merc M2 210 hp. I’ve owned it for three years.
350 hours
I have always had trouble getting it started from a cold start but once it runs it runs very well. 50 mile an hour plus
I am checking out fuel system and ignition system including spark.
Just did a compression test and did not like the readings. I like the consistency but not the compression. How bad is it?

Sea-Doo compression
87 top Starbord
90 Centre starboard
85 bottom starboard
85 top port
87 middle port
90 bottom port

Numbers are on the low side, which begs me to ask-
Did you check compression at full throttle with all plugs out and a fresh, fully charged battery? On the 240 EFI, the numbers should be 135psi. I don't know if there is supposed to be any difference. What RPM are you getting at WOT?

Is your lift pump working properly?

 

[Fonz]

Numbers are on the low side, which begs me to ask-
Did you check compression at full throttle with all plugs out and a fresh, fully charged battery? On the 240 EFI, the numbers should be 135psi. I don't know if there is supposed to be any difference. What RPM are you getting at WOT?

Is your lift pump working properly?

 

[Fonz]

Compression tests were done on a cold engine with all spark plugs removed and just cranking engine over. Battery was at full charge
I’m not sure about the lift pump. Is there a way to check it? Would that affect compression?

 

[Fonz]

Tim75
I just reread your reply and realized you were asking about 2 different issues. Sorry. The lift pump is working. I had a faulty anti siphon valve at the fuel tank which was allowing fuel to drain back into the tank. Hoping that was the start issue.

 

[Tim75]

Tim75
I just reread your reply and realized you were asking about 2 different issues. Sorry. The lift pump is working. I had a faulty anti siphon valve at the fuel tank which was allowing fuel to drain back into the tank. Hoping that was the start issue.

Again-
was the compression test done at WOT? It should be, so you will get the highest numbers.

 

[Fonz]

Again-
was the compression test done at WOT? It should be, so you will get the highest numbers.

 

[Fonz]

I did a second compression test and did have WOT. The numbers went up slightly. Only about 2 to 3 pounds per cylinder. I’m still very low on compression but very consistent. I will try again with a different compression tester.

 

[ripcuda]

Those #'s are low... but at least they are relatively even. I'd second the advice of trying a different compression tester just to be sure. All plugs out, strong battery, throttle to WOT. My engine #'s are 130-135 across the board. Cheers!