This summer I put an impeller in this old style Sherwood pump (OE on my Oday 85) after seeing weak water discharge out exhaust. Pumped great for 4-5 weekends. Now the boat just sat for a month and today I fired it up. Almost no water discharge, but a look at the pump showed a lot of water coming out of the weep hole on flange bottom side. Doubt there is anything to do other than pull it off and replace or rebuild. Had Depco (good folks!) rebuild it in 2011 so I wonder if re-building again really makes the best sense. Thoughts on rebuild or replacement and,if the latter ,with Sherwood or Oberdorfer? (Engine is '85 Universal M-12).
Sherwood Pump "weeping" water
- Thread starter odaydokay
- Start date
I had this problem on my Hunter, which had a water pump that was relatively easy and cheap to rebuild. But you don't want to be worrying about critically important parts on a 30+yr old boat So I did both: I bought a new pump from Depco and also rebuilt my OEM pump to keep as an emergency spare.
Take the pump off and put new seals in. This link is for an Oberdorfer. Get rid of the crappy Sherwood.
Links for you:
Oberdorfer Pump Rebuild 101 - http://c34.org/bbs/index.php/topic,6766.0.html
Why SHERWOOD Raw Water Pumps leave a LOT to be desired: See reply #6 here: http://c34.org/bbs/index.php/topic,8493.0.html
Links for you:
Oberdorfer Pump Rebuild 101 - http://c34.org/bbs/index.php/topic,6766.0.html
Why SHERWOOD Raw Water Pumps leave a LOT to be desired: See reply #6 here: http://c34.org/bbs/index.php/topic,8493.0.html
I see your point. I think I will spring for an Oberdorfer. Is this a straight bolt on replacement on the M-12? I saw some photos/videos that show the Oberdorfer hoses coming off differently than mine which come off my Sherwood at 7 and 11 O'clock, Oberdorfer like 11 and 2 about. Also, how can I be sure to get the correct model pump. Don't need an error in that area. Depco still best source?
What was pump type that failed? Sherwood or Oberdorfer?
What pump did you buy new? S or O?
When I called Depco to ask about a replacement for the Sherwood pump on my M25XP the person on the phone asked me several questions about the Sherwood pump to ensure I had the proper replacement.
The replacement installed easily and has been running fine.
The replacement installed easily and has been running fine.
And you simply cleaned off the flange face, installed the new pump without greasing the shaft or putting Vaseline or similar on the new flange gasket?
Correct. I was ready to lube the impeller but it was already done.
The replacement pump mounted using L shaped brackets to lock it in place which was different from the Sherwood pump but no problem mounting it.
I had an OEM Yanmar raw water pump. A pricey item. I called Depco and they guaranteed that a replacement Johnson pump, at about of third of the cost of the Yanmar pump, would fit and work. It did and does. I like Depco.
Those things are easy to rebuild.. The seals are generally less than $10 and a pair of good sealed ball bearings is $15 or so.. This for a Yanmar, but very similar (if not identical) parts for the Oberdorfer and Sherwood pumps.. I encountered one pump on a Westerbeke that had bronze bushings instead of ball bearings.. a booger to rebuild.. We used some graphite impreg bronze to turn new bushings and added a grease injection point.. Never had to work it again..
Now my story turns really wacky. I pulled the pump to send it to Depco and decided to have a look at the impeller. New in June it should still look ok I figured, but you know, curiosity.... One vane broken, but the real surprise was no circlip holding the impeller on the shaft! Wonder if I bent it putting the impeller in, but heck it ran for probably 50+ hours so doubt that was it. Not usual to see something like that, but without it I can see where the pump would not run right.
Well, the verdict on this was badly worn parts especially the sloppy shaft which apparently helped the new impeller to fail so fast. Total cost to refirb too close to the cost of new to be worth it so I ordered up an Oberdorfer N202M-15, better than the original Sherwood by all accounts. Was told it's a good idea to wet it up inside before attaching the hose for the first run up. Makes sense so it does not run dry even for a second or two. I will try to remember to do that start of each season and for my winterizing as well.
Have now installed the Oberdorfer. Works fine, but I am left with a new in package impeller kit for the Sherwood. Part Number 33100. Free to a good boat if I you pay the postage.