Yanmar 3 cylinder - cooling leak

[Deepdraft]

Hi,
I have a Yanmar diesel that leaks water out of a 90 degree fitting at the back and top of the of the engine, same level as the the fill cap, ( directly behind it). I can spin the fitting by hand. I'll post a picture later today. Anyone ever see this?

Thanks,
Neil

[Deepdraft]

This is not my engine, but the fitting is just ahead of the exhaust elbow, copper colored. Thanks.

[Chuteman]

What is your exact engine model #?

[Deepdraft]

it's a 3GM30F.

[Astral Blue]

The picture is not very clear, but the fitting seems to have a bolted flange connection. If that is the case, then no. The fitting cannot be spun off. It needs to be unbolted and the gasket would need to be replaced during reinstallation.

[bobconnie]

It's hard to tell with the wire in the way But it sorta looks like it might be a pipe thread bottom theres sure a wrench flat behind the brass hose fitting, if so maybe it's striped? just a thought, if the wire was moved we could really see the fitting ! this engine is unfamiler to me sorry thats all I can come up with

[Deepdraft]

Here's another shot of a Yanmar

[Noname]

If I'm looking at the right fitting it is the saltwater plumbing leaving the heat exchanger and going into the exhaust elbow. However, I may be missing the fitting you are referring to.

[Deepdraft]

Correct... on my boat that fitting has a hose going up to a siphon break, (U shaped), the return comes back into the exhaust mixing elbow.

[Chuteman]

Was using search engine to see if someone had loaded a Service Manual / page, no luck yet
Here's drawing of your engine that confirms finding
Yanmar 3GM30F drawings - Marine Power Ltd. - Yanmar - Mercruiser - Hydrive

picture
Yanmar 3GM30F - Marine Power Ltd. - Yanmar - Mercruiser - Hydrive

Looks like hose over with clamps

[bobconnie]

What ever ! if it's spining around and leaking, it's Broke ! LOL has to come off and be repaired! no getting around that ! see if it has bolts holding it down if not its treaded ! change it and your good to go ! sorry but thats the only answer I can see ! Not being a wise ass but it needs to be fixed LOL

[Deepdraft]

I don't think it's threaded... it may have a flange nut under, and inside the exchanger...??

[cal40john]

I think my diagram shows an o-ring on the elbow fitting, the bolt is what holds the fitting from coming out.

John

[Chuteman]

Better Photo

Yanmar 27HP 3 CYL WITH SHAFT DRIVE For Sale | Boats for Sale on Boat Deck

Appears that manuals - service & parts are avail - free or pay- search away
example
http://boatdiesel.com/Engines/Yanmar...ads-Page11.cfm

[Deepdraft]

There's a small set screw behind the fitting, I removed it and gently pulled up on the fitting, it didn't seem to want to come out, maybe I should pull a bit harder.