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Completed the compression test on my '85 merc 260

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Completed the compression test on my '85 merc 260

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Old 10-24-2004 | 07:23 PM
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Default Completed the compression test on my '85 merc 260

1- 132
3- 135
5- 130
7- 133
2- 155 noticed fuel in cyllinder
4- 150 also noticed fuel in this cylinder
6- 140
8- 145

How does it stack up? what does it mean when there is a noticeable amount of fuel in the 2 cylinders? Thanks guys. at least now I assume I have arrived at decision time. Thanks for any advice.

Jim
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Old 10-24-2004 | 09:06 PM
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Default Re: Completed the compression test on my '85 merc 260

Compression test should be run on a motor that is "warm" not cold.
Disable the kill switch (or if it does not have one, remove the coil wire from the distributor cap and ground it). Open the throttle plates.

Then check each cylinder.


When you say you saw fuel in the cylinders, please elaborate.
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Old 10-24-2004 | 09:30 PM
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Default Re: Completed the compression test on my '85 merc 260

yeah it was done cold. When I removed the #2 and 4 spark plugs I noticed fuel on them.
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Old 10-24-2004 | 09:34 PM
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Default Re: Completed the compression test on my '85 merc 260

Originally Posted by JGB
yeah it was done cold. When I removed the #2 and 4 spark plugs I noticed fuel on them.
fuel ..or water ?
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Old 10-24-2004 | 09:42 PM
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Default Re: Completed the compression test on my '85 merc 260

definitly fuel
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Old 10-25-2004 | 04:18 AM
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Default Re: Completed the compression test on my '85 merc 260

JGB you having probs or just got some extra cash ???
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Old 10-25-2004 | 08:13 AM
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Default Re: Completed the compression test on my '85 merc 260

It's certainly not an xtra cash issue. The Problem is max rpm only 4500, This motor has a little hotter aftermarket cam. engine iis running rough, carb has been rebuilt twice in two days. I'm at my wits end.

jim

Last edited by JGB; 10-25-2004 at 08:29 AM.
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Old 10-25-2004 | 08:18 AM
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Default Re: Completed the compression test on my '85 merc 260

Formulaz thanks, throttle was WOT during test. Carb as I mentioned in previous post has been rebuilt twice in two days ccause that's what I thought was causing the motor to run rough.
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Old 10-25-2004 | 08:20 AM
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Default Re: Completed the compression test on my '85 merc 260

And I am getting blow by from the Valve cover breathers and not just a little.
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Old 10-25-2004 | 08:25 AM
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Default Re: Completed the compression test on my '85 merc 260

was told engine had 40 hours on a rebuild. certainly can't belive that.

Jim
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