annoying oil leak

PW1967

Cadet
Joined
Apr 14, 2015
Messages
26
I have a 260 mercruiser that sits in a 1985 sea ray cuddy. Ive been trying to narrow down a engine oil leak that leaves a mess in the bilge after a day out in the water I added some dye to oil because I just could not find it on a black engine. It appears to be dripping from behind of the oil pan, Ive never had a boat engine out before but I believe that would be the bell housing, its kind of hard to see down there but with a mirror and flashlight it looks to be coming from a plate bolted to housing. Does this sound like a rear main seal gone bad or are their any other options to look at.
 

Rick Stephens

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Aug 13, 2013
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6,118
That's what it sounds like. Nice part is, pulling a boat motor is usually a lot easier than a car or truck motor.
 

alldodge

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Agree probably rear main, those engines had the two piece seal. Could just put an oil absorber cloth under the motor
 

wahlejim

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Jul 23, 2015
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884
I ran into a similar issue on my 1983 228, thought it was the rear seal because of the location, ended up being a cracked oil pressure gauge that I found while undoing hoses to pull the engine. It was located right by the distributor cap and oil was leaking down the rear of the engine.
 

Rick Stephens

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6,118
I ran into a similar issue on my 1983 228, thought it was the rear seal because of the location, ended up being a cracked oil pressure gauge that I found while undoing hoses to pull the engine. It was located right by the distributor cap and oil was leaking down the rear of the engine.



Good post.
 

PW1967

Cadet
Joined
Apr 14, 2015
Messages
26
thanks for the quick reply guys, It sounds like I may have another winter project to add to the list. I will have to do some double ckecking on that oil pressure fitting. A 40 mile trip and I lost about a quart. So I will be changing a lot of diapers.
 

NHGuy

Captain
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May 21, 2009
Messages
3,631
Look down the back of the motor on the port side from the top. If it's wet around there it could be the oil pressure sender. I also got a leak once from mine with a new valve cover gasket that i seated wrong back there.
 

JoLin

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Aug 18, 2007
Messages
5,146
One more thing to check if you have a remotely mounted oil filter. There's a block-off/bypass plate under the engine (port-side near the rear) where the stock oil filter was mounted. Mine needed to be resealed.
 

Bondo

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Apr 17, 2002
Messages
70,465
I will have to do some double ckecking on that oil pressure fitting. A 40 mile trip and I lost about a quart. So I will be changing a lot of diapers.

Ayuh,..... Welcome Aboard,.... A digital camera will put yer eyes, where yer head won't fit,....

Great for findin' leaks,....
Find oil, look higher, no more oil, ya just went past the leak,...
Oil, like 'bout everything else, flows Downhill,....
 
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