Yanmar fresh water pump failure

[Boatface]

The fresh water pump (NB NOT the raw water pump) on my one-and-a-half-year-old Yanmar 3YM30 engine has failed after only 350 hours. The bearings are shot and grease and cooling water has leaked out. I had understood that this pump was considered to be highly reliable, and have never seen this happen before .. certainly not on a nearly new engine.
1. Has anyone seen a similar problem?
2. What might cause premature failure of the pump bearings?
3. How easy would it be to replace?
Thanks

 

[pvb]

Sounds like it should be a warranty claim...

 

[Boatface]

Thanks .. what .. a bad pump or a bad installation?

 

[RichardS]

I agree with PVB. A warranty claim should yield beneficial results.

Sometimes fresh water circulation pumps do just fail. I've seen pumps in cars fail in under 20,000 miles. The only things which can decrease the life of the pump are running it without water, running it without antifreeze/inhibitor and running it with the belt too tight. In the absence of any of these, it must be a manufacturing fault.

Richard

 

[Boatface]

Thank you. I think it must have been a too tight belt. Would that be the responsibility of the installer or the manufacturer?

 

[pvb]

Thank you. I think it must have been a too tight belt. Would that be the responsibility of the installer or the manufacturer?

Doesn't matter, any claim you make will be against the retailer who sold you the engine.

 

[coopec]

Yanmar 3YM30 Raw Water Pump Failure - Cruisers & Sailing Forums
www.cruisersforum.com › ... › Engines and Propulsion Systems
Feb 11, 2009 - 15 posts - ‎7 authors
Since that time I have gone through 3 raw water pumps. The pumps are built of low quality metals and the first thing that happens is the pump ...
Yanmar fresh water pump 15 posts 14 Aug 2017
Yanmar Water Pump Leak 15 posts 15 Nov 2016
Yanmar 3ym30 Fresh Water Pump: Seal Leaking 3 posts 9 Apr 2011
Fresh Water Pump Overheating on Yanmar 3HM35 15 posts 15 Nov 2015

Yanmar 3ym20 pre mature water pump failure - SailNet Community
https://www.sailnet.com/.../58513-yanmar-3ym20-pre-mature-water-pump-failure.ht...
Sep 30, 2009 - I have a 2 1/2 year old 3ym20 with about 400 hrs on it. After returning from a six week cruise I found the raw water pump leaking. I thought it ...

 

[pvb]

Yanmar 3YM30 Raw Water Pump Failure - Cruisers & Sailing Forums
www.cruisersforum.com › ... › Engines and Propulsion Systems
Feb 11, 2009 - 15 posts - ‎7 authors
Since that time I have gone through 3 raw water pumps. The pumps are built of low quality metals and the first thing that happens is the pump ...
Yanmar fresh water pump 15 posts 14 Aug 2017
Yanmar Water Pump Leak 15 posts 15 Nov 2016
Yanmar 3ym30 Fresh Water Pump: Seal Leaking 3 posts 9 Apr 2011
Fresh Water Pump Overheating on Yanmar 3HM35 15 posts 15 Nov 2015

Yanmar 3ym20 pre mature water pump failure - SailNet Community
https://www.sailnet.com/.../58513-yanmar-3ym20-pre-mature-water-pump-failure.ht...
Sep 30, 2009 - I have a 2 1/2 year old 3ym20 with about 400 hrs on it. After returning from a six week cruise I found the raw water pump leaking. I thought it ...

Did you read the OP? It's the fresh water pump which has failed.

 

[coopec]

Did you read the OP? It's the fresh water pump which has failed.

But virtually all the links are to Fresh Water?? (Have a look at the links)

 

[RichardS]

But virtually all the links are to Fresh Water?? (Have a look at the links)

On my PC the links don't actually seem to be links.

Richard

 

[pvb]

On my PC the links don't actually seem to be links.

Same on my computer.

 

[coopec]

On my PC the links don't actually seem to be links.

Richard

Yes you are right. Most forums you can click on the hyperlink (anchor text?) and go to the article referred to. With this forum it seems you have to google the main heading eg "Yanmar 3YM30 Raw Water Pump Failure - Cruisers & Sailing Forums" and you can proceed from there.
Don't ask me why.......

 

[earlybird]

If a tight belt has done for the water pump bearings so quickly, it probably hasn't have done much for the alternator bearings either.

 

[jiris]

If a tight belt has done for the water pump bearings so quickly, it probably hasn't have done much for the alternator bearings either.

Don't know which Yanmar it is, but my 3JH2 need a fairly tight belt because of the small angle of wrapping over the alternator pulley. If not REALLY tight, it is slipping under load. A rather unfortunate design, I'd say. Neither bearing has failed yet, but I don't have a good feeling about it.

 

[Tomahawk]

I have had one fail.
ten year old engine

You will need a 12 mm ratchet ring to get at one of the bolts.

But if the MCA has it's way, you won’t be allowed to repair it yourself.

Unless trained and/or qualified to do so, safety critical maintenance should not be carried out by the owner / managing agent or skipper.