Ski, help! Yanmar water pump dripping coolant

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cardude01

Guru
Joined
Nov 26, 2012
Messages
5,290
Location
USA
Vessel Name
Bijou
Vessel Make
2008 Island Packet PY/SP
We've been running the genny pretty hard this trip. Wife has been feeling hot at night so I've been running it at night, and even during the day sometimes if it's super hot and sticky.

Got back from Grabbers this evening after a few of their special cocktails. I fired up the gen to get the place cool for showering and cooking dinner, and my wife said sethomg smelled funny. My smeller is not as good after breaking my nose a couple of years ago, but I opened up the gen enclosure and saw some coolant drips from the water pump, and I finally smelled the coolant smell of woe.

So my questions are, how hard is it to replace that pump and more importantly, will I be able to find one? (At Marsh Harbour maybe?)

This is a Yanmar 3TNV76. Pump seems easily accessible.
 
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I am not Ski obviously and certainly not an expert with your genset but if you have a drip of coolant it may just be a question of gasket, a loose clamp or something like that...

L
 
Lou,

True. I didn't investigate too closely tonight because I had been drinking, but my hunch is a leaking seal at the WP shaft. I got this gen a little hot before the trip due to a clogged heat exchanger and thinking that made the WP give up the ghost. Will look closer in the AM.
 
Here is a link to the Yanmar factory service manual in case you don't have one. Chapter 8 covers the cooling system. It looks pretty straightforward if you can get the correct pump. It's a common industrial engine so it might be fairly easy to source.

Lotsa luck:thumb:
 
Looking through the repair manual (thanks) I now wonder if I may have caused this dripping leak at the shaft. A few days ago the belt started slipping so I tightened it up super snug, but maybe too snug as I read about the correct tension. Sigh.

The drip, which appears to be coming from the WP pulley shift, is just a very slow drip......drip when the gem is running. Is there some kind of sealant or "stop leak" additive that might get the through the trip?
 
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What gen model is it? The 3TN is used in lots of machines like bobcats, etc. But there might be differences in the water pump. Best to order one direct from the gen maker to avoid that problem. More pricey, but probably worth it. I have not changed the WP on one of those, but it should be pretty basic. A bunch of bolts to loosen, clean some gaskets, new pump and new gaskets. Refill coolant.

There are companies that can get one shipped in from the states. Marina operators and yards in Marsh are probably familiar with them as they deal with this all the time. They can get one on a passenger airplane and get it to you pretty quick.

In the meantime, try loosening the belt to normal tension and see if that helps.
 
What gen model is it? The 3TN is used in lots of machines like bobcats, etc. But there might be differences in the water pump. Best to order one direct from the gen maker to avoid that problem. More pricey, but probably worth it. I have not changed the WP on one of those, but it should be pretty basic. A bunch of bolts to loosen, clean some gaskets, new pump and new gaskets. Refill coolant.

There are companies that can get one shipped in from the states. Marina operators and yards in Marsh are probably familiar with them as they deal with this all the time. They can get one on a passenger airplane and get it to you pretty quick.

In the meantime, try loosening the belt to normal tension and see if that helps.
It's a Maspower 8KW generator-- came with the boat. When I went to check it again this AM the stupid RAW water pump was also dripping at the shaft so I'm just mad at it now. Went to Nippers all day today so will try to regroup and think of something tamale.
 
Greetings,
Mr. dude. Nippers? Ah. I sorta remember Nippers...


200w.webp
 
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We just had a swarm of charter boats come in and anchor all around us. This always terrifies me.

But that's what I get for coming to this spot I suppose.
 
My smeller is not as good after breaking my nose a couple of years ago, but I opened up the gen enclosure and saw some coolant drips from the water pump, and I finally smelled the coolant smell of woe.

This is a Yanmar 3TNV76. Pump seems easily accessible.


Our genset uses a 3TNE-something. 74 I think. Anyway, in ours, coolant and raw water pump don't come together in the same sentence; a leak from our water pump would be sea water.

??

-Chris
 
The engine water pump is dripping coolant, and the recently replaced raw water pump is dripping sea water.

Headed to Mangoes in Marsh Harbour to try to sort it out.
 
Had a spare raw water pump on hand and got it installed, but no luck finding the coolant water pump. The leak at that pump is just an ever so slight and occasional drip. What about putting some "stop leak" or some such stuff in with the coolant ? Think that would maybe seal the pump leak? Seems unlikely but thought I'd ask.
 
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Last year I was wondering if stop leak can be used in a boat or if there is any risk to clog the heat exchanger. I emailed the company selling Bar's Leak to ask and never got any answer so still wondering.

L
 
Yeah that's what I worry about , clogging up the exchanger tubes.

Got ahold of Mastry Engine in St Pete, a distributor for these Maspower generators. They are looking for a pump and say they can ship to the Bahamas.

K9medic, when are you coming to GTC to get your boat?
 
have you tried marsh harbour boatyard? they are a yanmar dealer. they got us a fw pump a while back. took about a week.

if you buy from states direct, send vendor a copy of your cruising permit to avoid bahamian customs duty.

john
 
Got the pump! Ordered one from Mastry in St Pete and had it sent to K9medic, and he flew it over to GTC. That’s some next-level serendipity!
 
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