It doesn't end

captchuck

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Starting a new post due to a new problem. Can't get the engine to stop running rich and just had the carb rebuilt. Figured lets check/ change change the plugs. So I find water on tips of 3 plugs (port side) and then check oil which is brown and level way above full on dipstick. Motor not overheating and no drop in oil pressur but obviousely getting water in the oil. Oh and checked the oil last a few trips ago so maybe 8-10 running hours ago.
Any thoughts?
Where should i start diagnosing?
 

plowin

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My guess would be exhaust risers. Put a pressure tester on your expansion cap and pressurize to 5-8 lbs, if it holds its not likely that it is an head gasket. How old are the risers? Have they ever been boiled out? Do you have an oil cooler? Have you been diligent with your zinc changes in the exchangers? Even with all the questions I am going with exhaust risers. At least it happeened at the right time of year. Plenty of time to figure it out!!
 

captainlarry84

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KristenFormer Charter Captain
Cam Chain

It sounds like your cam chain is stretched a little and the risers are not high enough. What is happening is that a low speed and idle with the slack cam chain both valve stay open a little to long and the vacuum of the motor is able to suck in some exhaust water into the motor. Stretched cam chains are fairly common and does not pose a problem because once the boat is up on speed the chain is tight. In addition most boats have raiser high enough to defeat this problem, however in your case it my not be so.
 
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captchuck

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It sounds like your cam chain is stretched a little and the risers are not high enough. What is happening is that a low speed and idle with the slack cam chain both valve stay open a little to long and the vacuum of the motor is able to suck in some exhaust water into the motor. Stretched cam chains are fairly common and does not pose a problem because once the boat is up on speed the chain is tight. In addition most boats have raiser high enough to defeat this problem, however in your case it my not be so.

That's a thought I definitely didn't have which could also explain some other things too. You check that by how many degrees your crank moves before your rotor does?
 

captainlarry84

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That I am not sure. With the boat in the water remove all the plugs and spinner her up with the started. See if any water spurts out. With a cam chain problem and low risers you will get the most water at idle. What kind of boat is yours? The problem can be correct with exhaust work. It was very common it the 30’ Tara Pursuit.
 

captchuck

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Well fished yesterday on another boat in an effort to forget about my engine woes. Did a compression test this morning and found my number 3 cylinder to be completely dead. So I have water in my oil and no compression on one cylinder and the rest were all right around 60psi. head gasket? Or could it be something else?
 

captainlarry84

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60 sound low. It could be a head gasket if you are luck. However based on the wet plugs that you had my feelings are the water ingestion do to the exhaust valve staying opened to long at low speed. The water could have pitted your cylinder wall and/or the ring might be stuck also do to the water ingestion. Time to pull the heads.
 
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