chocolate milk in the crankcase

art_yatsko

Cadet
Joined
Jul 26, 2004
Messages
18
is there an easy way to tell if the milky brown stuff in my crankcase is oil mixed with sea water or oil mixed with anti-freeze? (Without tasteing it!)<br /><br />Checked all the usual suspects and need to narrow down the source. (It's FWC.) I've had a boat guy and the engine rebuilder chasing the problem w/o success. Thanks.
 

Bt Doctur

Supreme Mariner
Joined
Aug 29, 2004
Messages
19,344
Re: chocolate milk in the crankcase

FWC what?<br />If it sat for 2 or 3 years could be just condensation
 

art_yatsko

Cadet
Joined
Jul 26, 2004
Messages
18
Re: chocolate milk in the crankcase

1996 454 mercruiser, I/O. Re built this spring. got lots of noise about 40 minutes into test run. oil pressure went up as RPMs came down. Hauled, pulled, and broke down engine. bearings shot, crank 2 thouandths out, etc. Block tests to 40 pounds, heads were tested or magged?? (Not sure which, but passed) Exhaust manifolds new, risers newish, oil cooler tested to 45 pounds, etc. If it's salt water it must be the risers, Yes? Or would that have put water in the cylinders and cause a hydro lock. (bang, break, stop.) If it's anti freeze it's a bad block.... maybe? or?
 

Haut Medoc

Supreme Mariner
Joined
Jun 29, 2004
Messages
10,645
Re: chocolate milk in the crankcase

Bad risere would let water into the cylinders & into the oil but if it was just rebuilt it would take awhile for it to seep past the pistons.....The wrong cam could do it because of valve overlap.....Anti freeze would mean a cracked/porous casting or a leaky head gasket but then again it would take awhile to seep past the pistons, and you would have overheated...I would think if it was anti freeze, it would look like anti freeze in the oil. Was there water in the cylinders when you pulled it apart? Once you identify if it's water or anti freeze you will narrow down the possibilities. Go on taste it :D Just kidding!....JK
 
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