Merc. 3.0 water in oil ! ,what are some problem areas??

[dtigner]

I having no luck with another boat I purchaced not to mention I'm NEW to BOATING so laugh if ya need too because I don't have a clue ,Its got a 1984 3.0 merc I/O 140 (181 CID) in it and I changed the oil and it looked like a light gray milky color. I know the boat sat for a season uncovered + the engine cover half rotted away!(IN OHIO!) from the guy I bought it from (freakin idiot) so anyway I have no idea were to start on this engine to find out if I got a crack or just water from rain....? or what! <br />I can tell you that it runs well,no misses or back firing. I changed the oil three times and tried getting rid of the water/milky crap out. Still its light grayish in color BUT its building compresion and the oil is thicking up and slightly changing to a oil color so I don't know if there is just left over water/oil still mixing with the new oil still or what.Compression was 130,130,130,125 with darn near water running in it for oil the first time so I know I have good comp.I've only been testing the engine off of a hose hook up for 10 min and shuting it down afraid of damaging it even more. <br />Is there a way to really flush this engine of the residue(rinse out the GRAYISH MILKLY OIL)it just seams to stick in there, and put clean oil in with some type of cleaner for internal use??<br /><br />OR if I'm getting water in my engine from my hose hook up when test running what areas should i be looking at for leaks??<br />I looked all over this thing no visable cracks or leaking externaly,plus a good compression check! could this be a case of serious rain water from not being covered?? ANY THOUGHTS WELCOME!!!

 

[Trent]

Re: Merc. 3.0 water in oil ! ,what are some problem areas??

Could be rain water? Change the oil a few times and go run it. If water is back,then its time to remove the riser and manafold for a pressure check. My bet is they have never been changed. While you have them off look down the exhaust pipe at the shutter and see if its still their and in good shape.

 

[imported_Mike_M2]

Re: Merc. 3.0 water in oil ! ,what are some problem areas??

I agree, change it a few more times and let her rip. Once water gets in like that, it's tough to get it back to clear oil. Right now, just make sure the oil is good enough to run it without damage until you know for sure it was only rain. After that, do a very good flush.

 

[Bizmark]

Re: Merc. 3.0 water in oil ! ,what are some problem areas??

Make sure you're also changing the filter each time you change the oil.

 

[dtigner]

Re: Merc. 3.0 water in oil ! ,what are some problem areas??

Hey Thanks for the replies,<br />Trent- I would of never thought of even looking at those things.<br /><br />Mike- Its almost a bad joke ! (like trying to get Vaseline off of you car wiper blades)!<br />Don't ASK... <br /><br />Bizmark-I guess buying $50.00 worth of oil & filters is cheaper than a new Engine....<br /><br /> Thanks

 

[gtaeza]

Re: Merc. 3.0 water in oil ! ,what are some problem areas??

I don't think rain was the cause of that milky oil. Removed the cylinder head and have test pressure if there is crack, if its okey remove the<br />manifold and if its too rusty chaged it, remove the riser and check for crack and blockage.Make sure that if you install the new gasket there is<br />a sequence to tighten the bolts and proper torque. Good luck.

 

[Trent]

Re: Merc. 3.0 water in oil ! ,what are some problem areas??

Actually George.. I dont think rain was the cause either. But Im not their. I dont want anyone to pull major parts off an engine til they can do the cheaper stuff first. Normally the riser is the problem with water in the engine oil. But the manafold and riser need to be pressure checked first. (cylinder heads cannot be pressure checked, at least not that I know of) I Zyglo or magaflux them to check for cracks. Just to add.. This is sorta a poormans way to check and I cannot recommend it for the danger... But remove the manafold and pour gas into it and see if it leaks where it should not. Also the riser. Gas leaks into cracks where water will not. I cannot recommend this due to danger.....but it works most of the time. Cheep and easy.

 

[gtaeza]

Re: Merc. 3.0 water in oil ! ,what are some problem areas??

How old is the boat. If the boat is 15 yrs. old 95% there is crack on the manifold. Only two weeks ago I got the same problem I removed the cylinder for test everything is okey so I put it back with new head gasket and test run in the lake for two hours still another milky oil. I installed a new manifold test run for 4 hrs. yesterday in the lake the oil seems a like a black color but no more water mix.