Very leaky water pump on our newly purchased 1990 Hunter 335. I Googled it but cannot find a replacement raw water pump or even a rebuild kit. Any suggestions would be greatly appreciated. OEM, different mfgs, etc... Otherwise the engine seems to run great (however it looks rough), we motored her for 5hrs up to the DIY marina in St. Pete. The boat is on the hard for at least another two months and I'd like to check this box before relaunch.
Yanmar water pump (20HP)
- Thread starter ingeanous
- Start date
.... so are rebuilt kits available from these dealers; but, you need to also have the shop manual as rebuilding is not simple because of the set-up clearances for the bearings, seals, etc.
Bring your mortgage application when buying either a new pump or rebuild kit.
Bring your mortgage application when buying either a new pump or rebuild kit.
New boat and engine to us but am starting to draw the line in the sand w/repowering ($9Kish) vs sinking money into the old. We've been down this road before w/our old US30 and decrepit overheating Volvo and refitted her with a Beta Marine 16. Unfortunately she got trashed in storage and was a total loss and are staring all over again w/this boat.
Try www.depcopump.com. They are great, much better prices than Yanmar. Best to call their 800 number.
Try Mastry Engine Center LLC a Yanmar company and regional parts distributor. They are located at 2801 Anvil Street North, St. Petersburg, FL 33710. If the engine is running good it can be a keeper. I mean removing grease, dirt and rust and giving it a protective paint coat is not that hard and can save much money on a repower. Regarding the raw water pump, just determine where the leak is, if it is by the bearings it means the seal is shot and the unit is best replaced but if it is by the removable impeller cover then it is just a gasket which can be replaced. Either way is cheaper than repowering.
Ingeanous, I PM'ed you to try arrange sending you the rebuild instructions but got no reply. I suppose you've had a solution to your pump problem already. Good luck. Cheers! 
** finally, managed to upload the work instructions. :dance:
** finally, managed to upload the work instructions. :dance:
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You wont need all the parts. If bearings are ok, no need to change. If no groove on shaft, can reuse. Oil seal MUST regardless of condition. Use marine/waterproof grease. Mobile or Shell. Remember when installing pump, don't tighten the belt too much. Give it some slack. If belt is tight, shaft will leak within months.