Is this a sign of water getting in my cylinder?

mike64

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Apr 10, 2008
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...Or am I just being paranoid?

'72 Evinrude 65HP. The last couple times I've checked my plugs after taking the boat out I've noticed a little bit of whitish looking oil/fuel mix on the 1st cylinder plug. It feels like oil/fuel, but with the problems I've had with milky lower unit oil I'm wondering. The light color of the oil deposit on the plug is the only sign I have that there may be water getting in. I've seen plugs that were getting too rich of a mix, and the oil deposit is dark brown.

A compression test came out great-- ~134 PSI on all cylinders, +/- 1 PSI. I just had the boat docked on a lake this past week, took it out many times and the motor ran fine.
 

tashasdaddy

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Re: Is this a sign of water getting in my cylinder?

pull plug out, after running, have some one turn motor over , watch what comes out of the plug hole. had a 3 cyllinder yesterday, center cylinder, blowing water all over the place
 

mike64

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Re: Is this a sign of water getting in my cylinder?

Thanks TD! I ran the motor to warm it up before the compression test, and I didn't notice any moisture that came out of the cylinder when I did the test (had all plugs out). But I wasn't really looking for water shooting out. I'll do it again with a closer look at what's coming out of there. I'm thinking if there is water getting in that cylinder, it's a very small amount.
 

mike64

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Re: Is this a sign of water getting in my cylinder?

I just noticed this post that's very similar to mine:
http://forums.iboats.com/showthread.php?t=342885

Take out #1 and #2 spark plugs and peek into the cylinders through the hole. If #1 is significantly cleaner than #2, you might have a water intrusion problem...
If the #1 piston looks reasonably dirty, you can go with the condensation theory.

hope it helps
John

My #1 piston definitely looks "reasonably dirty", so I guess that's a good sign...?
 
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