water in oil

Jeffreyi

Petty Officer 2nd Class
Joined
Jan 9, 2007
Messages
107
Re: water in oil

Thanks Bondo.

Are you suggesting both the fuel filter and the water seperator?
 

Jeffreyi

Petty Officer 2nd Class
Joined
Jan 9, 2007
Messages
107
Re: water in oil

I changed both fuel filters. When I get to 2200 rpm's that as far as it will go on the water. The prop is turning, but there's no more power. Usually I can get it to 4000 rpm's.
 

Fishermark

Vice Admiral
Joined
Oct 19, 2003
Messages
5,617
Re: water in oil

Pull the plugs and see how they look. You can also check out the sticky at the top of the page - I believe Don S has a post about what to check when troubleshooting a failure to reach rpms.
 

Jeffreyi

Petty Officer 2nd Class
Joined
Jan 9, 2007
Messages
107
Re: water in oil

Thanks.

I just found that sticky note. It has alot of good info. I'll pull my plugs as you suggested. What specically am I looking for?
 

wallerus

Seaman Apprentice
Joined
Jan 8, 2010
Messages
32
Re: water in oil

Some points to check.

Small block chevys in boats are notorious for the intake rusting thru under the thermostat housing (water in oil).

Check to ensure that the secondaries are opening while you are trying to accelerate above 2200 rpm (if you have a 4 BBL).

Pull the exhaust risers (after draining the manifolds) and check for evidence of leakage at the gasket or rust thru.

If the engine sat with water in the cylinders for any length of time the valves could be rusted and not closing properly.

DO A COMPRESSION TEST. Then do a leak down test.
 

Fishermark

Vice Admiral
Joined
Oct 19, 2003
Messages
5,617
Re: water in oil

I'll pull my plugs as you suggested. What specically am I looking for?

Anything - your plugs will tell you a lot.

Are some oily and fouled? Is there any hint of water droplets on some plugs? Are they all nice and tan? Are some so clean they look like they have been steam cleaned? Post what you find and you can get some good answers - even pictures would be good.
 

Jeffreyi

Petty Officer 2nd Class
Joined
Jan 9, 2007
Messages
107
Re: water in oil

I returned from a vacation yesterday and took my boat out today. It still only reached 3200 rpm's and I heard some missing at lower rpm's.

BUT there's a more serious problem.

As I was docking at idle speed the motor died and would not turn over at all. I checked the oil and sure enough there was some water in the oil. I pulled the plugs and turned it over and water squirted out. Only this time in cylinder #1 it kept squirting out. So, as you guys advised I squirted oil into each cylinder and gave it a quick turn and repeated the process (oil, quick turn).

I'm not sure if this is important info but I throttle high speed pretty quickly. Could oil have entered through the exhaust again?

Please help.

Thanks.
 

Fishermark

Vice Admiral
Joined
Oct 19, 2003
Messages
5,617
Re: water in oil

I'm not sure if this is important info but I throttle high speed pretty quickly. Could oil have entered through the exhaust again?

Not while accelerating. Only on a sudden deceleration is it possible.
 

Jeffreyi

Petty Officer 2nd Class
Joined
Jan 9, 2007
Messages
107
Re: water in oil

Thanks.

Yes, that's what I meant.

What about the water still coming out? Has water accumulated somewhere and is entering the cylinder? This is a engine with a cooling system.
 
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