View Full Version : 2GM Raw Water Pump

04-19-2010, 11:44 PM
Poor old water pump is on it's last legs - dripping like crazy, who knows how old.

I've found a Johnson pump that looks suspiciously similar, for about 1/2 the price of the Yanmar branded unit. The pipe connections are at slightly different angles, but otherwise it looks pretty much identical from the data sheet. I'll do a few measurements and see how it goes.

Alternatively I can do a rebuild, which is pretty simple and costs around $100 for parts, but from what I'm told the shaft will most likely need replacing or resurfacing (where the seal grooves it). I can get a friend to turn one for me on his lathe, but it's starting too look a bit too much hassle for the $100 I'd save.

Anyone had luck doing what I'm trying to do - ie avoid the absurd Yanmar prices?

Cheers, lockie

04-20-2010, 03:25 AM
rebuilt my 3GM pump a couple of months ago for the same reason. After 1500hrs of operation, a couple of seals and bearings, polished the shaft with some 1400 wet-paper and WD40, good as new!
Total cost, less than 20 USD!
Note that the original part number for the Yanmar original pump has changed, and looks more like the 'original' Jabsco/Johnson pumps with loose fittings!
New number is 728270-42002


05-04-2010, 06:00 AM
Well all fixed now. Got a reco kit shipped from Marinepro, replaced bearings seals etc and polished the shaft. All happy. Interesting to note the OEM and model of the bearings and seal - next time I'll buy them from a bearing shop for a tiny fraction of the Yanmar price!