Compression test.

jato1229

Seaman
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Jul 29, 2010
Messages
59
Did a compression test today on my 2002 200hp ficht. 4 were at 140 and 2 were 125. Should I be worried.
 

TampaNate77

Petty Officer 2nd Class
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Jun 6, 2012
Messages
117
Re: Compression test.

The compression between each cylinder should not be any more difference then 10-15 psi.
 

jato1229

Seaman
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Jul 29, 2010
Messages
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Re: Compression test.

That's what somebody else said. Does it work, what brand to use?
 

JB

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45,907
Re: Compression test.

Did a compression test today on my 2002 200hp ficht. 4 were at 140 and 2 were 125. Should I be worried.

No, unless you are one of those people who worry about getting struck by lightning.

OMC spec said all cylinders within 15% (NOT 15#) yours are all within 15%.

A decarb job might improve those numbers, but that is an iffy thing to do with a DFI 2 stroke.
 

boobie

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Nov 5, 2009
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20,826
Re: Compression test.

If you spray the de-carb through the intakes on a DFI it can run away on you and the mtr will shut off. Then you'll get a code 57 where it takes a lap top to clear the code so it will start again. Tilt it up with the plugs out and put the de-carb in the cyls and let it soak.
 

boobie

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Re: Compression test.

JB, one of the OMC manuals I have says no more than 15 PSI between cyls.
 

Haffiman

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Dec 17, 2009
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2,454
Re: Compression test.

Try to add some Carbon Guard to the fuel. Give it a good run and re-test. If the lower readings was on the port side, almost normal. If on stb, a bit more to be worried about.
 

JB

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Re: Compression test.

JB, one of the OMC manuals I have says no more than 15 PSI between cyls.

Yup. There are also OMC Manuals that call for a spark plug gap of .040". They changed their mind about a lot of things over the years.

Not a big deal, though. Jato's engine meets either spec.
 

boobie

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Re: Compression test.

You got that right about mind changing. I could tell you that first hand.
 

emdsapmgr

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Dec 9, 2005
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11,551
Re: Compression test.

Are the low compression cylinders the two bottom cyls? Starting around 1994, OMC designed some of their V6 engines to have lower compression in the bottom two cyls. I know the 60 degree Intruder-type engines ran lower compression in their two lower cyls. Was a long-term reliability thing. You may want to call Bombardier customer service and ask someone about your engine: 1-847-689-7090
 

jato1229

Seaman
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Jul 29, 2010
Messages
59
Re: Compression test.

Hey boobie, u were right on. Code 57 . How do I clear it. I have software and comp. I showed the guy this b4 he did it, he said never had a problums.
 

boobie

Supreme Mariner
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Re: Compression test.

Do you have the cable to connect the laptop to the mtr ??
 

Haffiman

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Messages
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Re: Compression test.

#57 is a code typical when people run on muffs and rev the engine in gear!!
It may even indicate a fuel leak into crank case from a broken lift pump membrane as well.
 

jato1229

Seaman
Joined
Jul 29, 2010
Messages
59
Re: Compression test.

yes, i have the cable. we were able to clear the code. anyway when he sprayed that stuff in boy did it smoke, alot of carbin washed away with the water. hope this helps.. hey boobie let me pick your brain, no wake zone the motor runs rough as if its running on 5cylinders and not 6.. if i give it a quick shot of gas then back off sometimes this helps. i did change plugs.
 
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