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post #23 of Old 08-07-2011
Learning the HARD way...
eherlihy's Avatar
Join Date: Jan 2007
Location: Boston / Ft Myers Area
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Angry Friggin Pump...

I've put about 30 hours on the engine since the pump rebuild. Realize that this is a new-to-me boat, and I just started a job, so my sailing time has limited. Also, it's a sailboat...

I noticed that the crankshaft oil-seal on the M25 was leaking, and spraying a fine mist of oil around the engine compartment. After every 3 hours, or so, I found what I initially thought was V-belt dust. When I wiped it up, however it smudged - thus cluing me in that it was a liquid....

Anyway, I pulled the oil seal - once I figured out that the seal is made of a metal ring embedded in the rubber (which took me about an hour to figure out), and inserted the new one (hint- even though it looks like it is only rubber, you cannot deform it by squeezing it with your fingers - thus it must have something rigid inside of it!). Then, I started the engine to check my work. No leaking oil! No spray! No specks on the engine mounting platform! Looks good!!!

... Wait a minuite, where did that drip come from?... There's another! Another, and another! It COULDN't be the raw water pump, I just rebuilt it!...

Clear as day, water was dripping out of the lower weep hole, and splattering on the engine block, the new engine mount (I no longer wonder why the PO replaced it), the oil pan - right where there is that rusty spot... Rate of about 1 drop / 2 seconds.

I guess that the pump housing is shot, and the water is making it's way around the seals... Or, and this thought is just occurring to me, there may be a restriction down stream (H/X or exhaust elbow) that is causing back pressure, forcing water to escape through the seal.

Would any of you like to share your experience with the Universal M series of engines, or hazard a guess?

I will look into it, but I suspect that a new pump is in my future .

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USCG Licensed OUPV Captain, ASA 101/103/104/105/106/114/118 Instructor - Also certified in Marine Electrical Systems

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