Slow water leak into oil

[rarc]

I've got a 120HP Mercruiser circa 1973.<br /><br />I bought the whole boat for $200 and have it running really well although she ain't pretty. I know the block froze with water in it last winter (hence the price) and I successfully fixed the external crack with JB Weld. <br /><br />However, when I take the boat out a slight amount of water is getting into the oil. It is only enough to show some swirls in the oil and barely discolor it. There is not a significant increase in oil volume. I'm almost positive it is an internal crack.<br /><br />The boat is not worth putting any money into (ie new engine or rebuild) so I intend to run it as is until it dies and then part it out. My question is what can I do to postpone the inevitable? I intend to change the oil often. Are there any additives, tricks or suggestions for prolonging the life of this old motor?<br /><br />Thanks in advance for your suggestions.

 

[quantumleap]

Re: Slow water leak into oil

Oil + Water= outboard death. Are you sure it's not a bad seal??

 

[rarc]

Re: Slow water leak into oil

No I can't 100% say its not. However, given the other freeze damage I'm guessing its a crack. I'm hesitant to start taking things apart because that means $ in a cheap boat as well as the chain reaction of the old parts needing replaced everytime I get into a repair. Its a gamble- put money in and maybe get a long term boat or lose the money altogether.

 

[JB]

Re: Slow water leak into oil

Moving to I/O

 

[Skipster1]

Re: Slow water leak into oil

Hey rarc, aren't you really asking if those water system sealers work? I"m talking about those poweder "sealants" that are supposed to flow thru the water system and plug up minor leaks.<br />Generally the usual thinkig is "DON"T DO IT" but, maybe, in your situation it might be worth a try. If you don't get a better solution you might try it. I'd add it SLOWLY to the water (add it fast and you're sure to get a big glob that might block the system)... take your time.... add some... run the engine for a bit... then add some more.<br />Bottom line is the stuff does plug up holes.... but, since you can't really control it, it might plug up the wrong orifice.

 

[xltier]

Re: Slow water leak into oil

maybe the leak will rust itself shut.

 

[tommays]

Re: Slow water leak into oil

i like your own idea best change the oil a lot and nurse it long as it will go it is good to see someone who understands that the boat is not worth puttting magor money into<br /><br />tommays

 

[rarc]

Re: Slow water leak into oil

Thanks for the inoput so far:<br /><br />I have considered trying sealants that go in the water but how do you keep a high enough concentration of the supplement with the fresh water constantly being sucked in and blown out. I have thought about ways to create a closed system with basically a barrel that collected the exhaust water and a hose/test gizmo that would suck it back up in. It seems like it wuld take a huge amount of additive to get a concentration that might be effective.<br /><br />I have also wished for it to rust shut. Any ideas on how to encourage that process?<br /><br />One other idea I had was to run a heavier oil. It wouldn't be the best for the motor long term but would it better resist the influx of water as well as maintain a higher viscosity as water mixed into it?<br /><br />Cost is a huge factor. The wife and I agreed not to purchase a boat for two years. This was so cheap we couldn't resist. However, for now its this boat or no boat.<br /><br />Thanks all

 

[Scaaty]

Re: Slow water leak into oil

Best advice is run it and change the oil, and have a decent kicker motor to get back on when it finally dies! That way you have a real deal at $200