2YM15 slow water leak from water pump area

[asahi]

I'm getting a slow drip of water, about 1 per second at idle coming from the vicinity of the water pump. It looks like it may be coming from the mounting area, as opposed to the intake or output.

I'm currently underway on the ICW in NC and am hoping that it will hold for another 200 miles or so. Any tips on identifying the exact location of the leak and repairing it? Could it be the impeller that needs to be replaced?

[SV Bacchus]

Are there two of you so one can watch what happens at cruising speed (RPM) under load? You heading N or S and will you be motoring the entire, or most of, the 200 miles? If the leak increases at speed/load you will/should probably be repairing before continuing.

I know I didn't answer the "where from" question but my random thoughts concerning the immediate need.

[s/v Moondancer]

While my engine is a different model...when I had a leak from the mounting area it was a failed o-ring within the mount. I would not play with it unless I was on a dock near a source of the correct parts.

I crossed half of the South Pacific with the leak because the nearest parts were 2,000 miles away!

[a64pilot]

Usually water pump seals fail slowly, a lot like the sink will slowly over time leak more and more until one day you replace the washer.
As we used to say, fly it and watch it.
If your going to do a lot of travelling, it's one of those things that I keep a spare.

Usually fail slowly, but no guarantee of course

[Jhowell5558]

Had the exact issue on my 2YM15 - rear seal on the water pump">raw water pump failed.

3 solutions:
1. Replace seal yourself - requires some tools, press, and a little expertise but
can be done. I tried this but found I really goofed it up worse - on to option 2

2. Throw money at the issue - order replacement RW Pump from Yanmar - seems
like they wanted $400 - TOO MUCH! - on to option 3

3. Found Home
OUTSTANDING company - sent my pump to them ($10 freight)
They totally rebuilt - looks like new - including freight back $125

Solution has been a win for me

[douglong]

Deaton yacht service in Oriental, NC would be the place that I'd go to take fare of the issue.

[four winds]

Does indeed sound like the typical pump shaft seal leak.

There are "weep" holes on the pump body to allow the leaking water to escape and also provide detection of the problem. On some engines, but not yours, the leaking water can enter the engine crankcase undetected without these holes.

If you look, maybe with a small mirror, you can see these holes and often some salt water corrosion on the pump body. On your pump mount bracket the leak should be dripping near the middle of the bracket. May be hard to see the holes with that channel shaped bracket.

You can continue using the engine but should repair this as soon as it is convenient. Monitor the issue with though, and do it sooner rather than later.

If 200 miles gets you "home" that shouldn't be a problem. And this is a repair you can do yourself if you are so inclined. It's not that hard and will help build confidence in your ability to take of things yourself.

Finally, my usual admonition to aquire a service manual for your engine. If you are mechanically inclined and can use a manual you may be surprised how much you can do yourself on common boat maintenance and repairs.

[seabreez]

Originally Posted by asahi

I'm getting a slow drip of water, about 1 per second at idle coming from the vicinity of the water pump. It looks like it may be coming from the mounting area, as opposed to the intake or output.

I'm currently underway on the ICW in NC and am hoping that it will hold for another 200 miles or so. Any tips on identifying the exact location of the leak and repairing it? Could it be the impeller that needs to be replaced?

All water pumps are the same. Behind the pulley on the shaft is a bearing, then an air space. At the bottom of that air space there is a hole approximately 1/4 inch and is there especially so that your engine coolant does not contaminate and deteriorate the bearing. Following that air space is a seal and that is the one causing your leak. To see this you need a mirror like the dentists use (available at some hardware stores or automotive parts places). a bright light and look under the cast iron immediately behind the pulley. When the engine is cold it leaks more. Depending of the leak... in a closed cooling system you need to keep a close eye on it and keep adding more coolant. The only fix is to change the water pump.

[SeaSon]

200 miles? That's barely leaving the neighborhood. Not sure if you're talking about the raw water pump or your coolant circulating pump, but either way, should not be an issue. Check it periodically while traveling, and order a replacement or repair kit for delivery at your destination.

Be smart, order two.