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wotan2525
07-22-2012, 03:30 PM
I'm really at my wits end here. Boat is overheating and not pumping any (or not much) water. Here's what I've done:

Removed water pump and impeller, sealed everything well with RTV to make sure that their were no air leaks. Visually inspected the impeller -- no knicks, no broken fins.

Flushed both hoses that connect to the water pump. One of them had quite a bit of old impeller parts in it. Was sure that this was the issue but has not made a difference.

Removed thermostat and flushed thermostat housing.

Boat runs fine on a hose.... I'm assuming because this creates positive pressure on the supply side. Here's the tricky part -- when I run the supply into a bucket that is hose fed, it will create TONS of suction. But ONLY if the system has been primed with the hose before that. If I disconnect the supply and allow air to get into the system, the water pump will not develop any kind of suction.

With the garden hose connected there doesn't appear to be any leaks in any of the hoses. Hard to inspect the one that runs under the engine, but it seems fine?

I've had to be towed in 3-times this season because of this!

CornRickey
07-22-2012, 08:55 PM
Sounds like your sucting air from somewhere. Once the pump is primed (by the hose) the pump draft is able to overcome the air leak. But its self priming ability isn't.

ngavchris
07-23-2012, 09:38 AM
I had the same problem a couple of years ago. Talked to skidim...... I had already tried a new impeller. Replaced the entire raw water pump and haven't had an issue since. The old one looked fine, but skidim said that they wear out and loose the capability to create suction.

cadunkle
07-23-2012, 10:52 AM
Typically the thrust/sealing surfaces on the front plate nad in the back of the impeller cavity will wear, so the impeller won't seal well. Once there's water in there it closes up the gap. On old style pumps with metal impellers they had grease zerks and you're give it a couple pumps before starting so the pump would prime.

wotan2525
07-23-2012, 12:51 PM
Typically the thrust/sealing surfaces on the front plate nad in the back of the impeller cavity will wear, so the impeller won't seal well. Once there's water in there it closes up the gap. On old style pumps with metal impellers they had grease zerks and you're give it a couple pumps before starting so the pump would prime.

There's got to be a rebuild option available. A new sherwood raw-water pump is $500. Tough pill to swallow!

92SupraComp
07-23-2012, 01:45 PM
skidim has all the parts needed to rebuild the pumps. they well priced except for the sealed bearings. $25 a pop!!! you can pick them up for way cheaper. but everything else is well priced

wotan2525
07-23-2012, 02:05 PM
skidim has all the parts needed to rebuild the pumps. they well priced except for the sealed bearings. $25 a pop!!! you can pick them up for way cheaper. but everything else is well priced

Sounds like you've done this? Any info on how I can figure out what I need? There is no extra play or slop in the bearings that I can feel. The overall condition of the pump is pretty good. I'll try to pull it back out and take some photos maybe....

wotan2525
07-23-2012, 02:25 PM
Found information about rebuilding. http://www.pumpagents.com/pdf/SherwoodPumps/G55-2.pdf

My pump does not (nor has it since I've owned it) had the "spacer plate." This is part #7 on the exploded view. Can anyone confirm that their pump has this?

sybrmike
07-23-2012, 02:36 PM
Yes, mine has the thrust plate (#7). I didn't know I had one either, but it came apart while disassembling the pump for general clean up and impeller replacement. I only had the impeller and o-ring from skidim on hand, so had to cut my own gasket ( #8 ) to finish putting it all back together.

92SupraComp
07-23-2012, 05:02 PM
Found information about rebuilding. http://www.pumpagents.com/pdf/SherwoodPumps/G55-2.pdf

My pump does not (nor has it since I've owned it) had the "spacer plate." This is part #7 on the exploded view. Can anyone confirm that their pump has this?

this is probably why it wont work. YOU NEED THAT PLATE. period. no questions. Its absolutely necessary to have that. Yes all the pumps need that plate. It seals against the impeller. Its a wonder that it creates any suction once its primed. I dont know how on earth you pump it working with that piece missing. It should fix all of your problems once you get one and put it in.

wotan2525
07-23-2012, 05:17 PM
this is probably why it wont work. YOU NEED THAT PLATE. period. no questions. Its absolutely necessary to have that. Yes all the pumps need that plate. It seals against the impeller. Its a wonder that it creates any suction once its primed. I dont know how on earth you pump it working with that piece missing. It should fix all of your problems once you get one and put it in.

I figured out part of it. The boat self-primes when it is moving forward. All 3 times when I've overheated this year was while I had started the boat while sitting still (filling up bags or jump-starting a jet-ski.) If you are moving, water is pushed into the intake grate and up into the water-pump enough to prime.

Here's the weird part. I've owned this boat for almost 10 years now. It's never had that plate and it's never had a problem. Weird, huh??

wotan2525
07-23-2012, 07:22 PM
I figured out part of it. The boat self-primes when it is moving forward. All 3 times when I've overheated this year was while I had started the boat while sitting still (filling up bags or jump-starting a jet-ski.) If you are moving, water is pushed into the intake grate and up into the water-pump enough to prime.

Here's the weird part. I've owned this boat for almost 10 years now. It's never had that plate and it's never had a problem. Weird, huh??

I lied. That plate is there. It was stuck to the housing and I just hadn't realized that it could be removed. It's got a groove on the inside edge of it that I presume is from the hub on the impeller. The rest of the wear-plate is smooth and groove free.

The water-pump cam is perfect.

The bore of the water pump housing does not show any grooves or pitting.

Bearings are all tight and spin smoothly. No roughness or end-play.

So.... I'm back to being stumped. The whole assembly is in my ultrasonic cleaner right now to knock off any corrosion or left over gasket material. In the meantime, I'm going to go measure the impeller compared to the new one that I've received on the off chance that my first one is too narrow? Just sort of grasping at straws at this point.

wotan2525
07-23-2012, 07:40 PM
In the meantime, I'm going to go measure the impeller compared to the new one that I've received on the off chance that my first one is too narrow? Just sort of grasping at straws at this point.

Impellers are identical.

Ptownkid
07-24-2012, 08:29 AM
Do you have a sea strainer? I had the exact same issue with mine and there was a really hard to see crack in one of the fittings.

SquamInboards
07-24-2012, 09:46 AM
+1 on the strainer - that can have tiny little air leaks, causing your problem. Is there a good o-ring on the strainer itself where it threads on?

wotan2525
07-24-2012, 09:53 AM
I don't have a sea strainer. I'm becoming more and more convinced that the problem is not with the water pump. I'm going to try and pressurize the intake side of the hoses and see if I can find a leak.

92SupraComp
07-24-2012, 09:59 AM
+1 on the strainer - that can have tiny little air leaks, causing your problem. Is there a good o-ring on the strainer itself where it threads on?

ours leaks but never prevents our pump from priming. well. what about piece number 21 on Pump Diagram (http://www.sherwoodpumps.com/FileAttachments/Marine-Distribution/en-us//Literature/MPG_3047_09959_TECH.pdf) that piece can wear out and prevent the pump from working. also it puts grooves into old impellers. but your seal and seat are prob shot like ours. Parts 13&14

wotan2525
07-24-2012, 11:22 AM
ours leaks but never prevents our pump from priming. well. what about piece number 21 on Pump Diagram (http://www.sherwoodpumps.com/FileAttachments/Marine-Distribution/en-us//Literature/MPG_3047_09959_TECH.pdf) that piece can wear out and prevent the pump from working. also it puts grooves into old impellers. but your seal and seat are prob shot like ours. Parts 13&14

The seal and seat may be worn. It looks like I might be able to get those off without having to press out the shaft? Can't really tell without starting to disassemble.

The cam (part #21) looks good on mine. There isn't any pitting or grooves in it. You can see where it has marked the impeller, but it's not like it has damaged it. Only left an impression (which to me indicates that it's fitting tightly against it.)

suprasam
07-24-2012, 12:12 PM
Have you thought about it being your "circ pump"? Not that I am suggesting that you just go and buy one, but just another straw to throw out there for you to check it over.

wotan2525
07-24-2012, 12:55 PM
Have you thought about it being your "circ pump"? Not that I am suggesting that you just go and buy one, but just another straw to throw out there for you to check it over.

Have thought about and dismissed. Water is not even getting to the circulation pump. When I disconnect the output hose on the raw-water pump, it's bone dry.

SquamInboards
07-24-2012, 04:26 PM
I do think you're looking at a new RWP. What pump do you have? I might have one around (used obviously), but it could be worth trying.

wotan2525
07-24-2012, 05:59 PM
It's the Sherwood 55-2. Let me know if you see anything.... I can take photos of the pump to show you that it doesn't appear like it has abnormal wear.

OUI
07-24-2012, 08:11 PM
How about a clogged water intake, intake hose or trans oil cooler. Try taking the intake hose off the trans oil cooler (at the water pump side) and sticking that in a bucket of water to see if it draws.

wotan2525
07-24-2012, 08:14 PM
Here's the shaft side of the housing. I pulled off the washers, seals and snap rings and will be replacing them.

http://i635.photobucket.com/albums/uu79/rbosworth/20120724_182913.jpg

Here is the wear plate. Does show a bit of wear but there's no way that this is enough to cause much of an air leak.

http://i635.photobucket.com/albums/uu79/rbosworth/20120724_182859.jpg

Here's the impeller side of the housing. The bore has some marking but none of those can be felt with a fingernail.
http://i635.photobucket.com/albums/uu79/rbosworth/20120724_182840.jpg

And the cam:
http://i635.photobucket.com/albums/uu79/rbosworth/20120724_182736.jpg

wotan2525
07-24-2012, 08:15 PM
And finally.... a video showing that the bearings spin pretty well still!


http://www.youtube.com/watch?v=LhEXAGZo3lw

OUI
07-24-2012, 08:59 PM
Looks like the shaft side of the housing needs some cleaning

ngavchris
07-24-2012, 09:15 PM
Mine looked just like that when I pulled it off; however, it would not get good suction when hooked up to a bucket of water in the boat. I searched for every reason why it wouldn't work and couldn't find one. Bought new pump, installed, problem resolved. I think I remember only paying around $350 for mine. That was a lot of money for me to spend, but well worth the result of not worrying about ruining my engine. Hope it works out for you.

docdrs
07-24-2012, 09:38 PM
You could buy a piece of cheap clear hose, connect it to the input side of the rwp and the other end into a bucket and start your motor. If it sucks the water out of the bucket you know its that side, if it does not then you know your pump is pooched.

wotan2525
07-24-2012, 10:17 PM
You could buy a piece of cheap clear hose, connect it to the input side of the rwp and the other end into a bucket and start your motor. If it sucks the water out of the bucket you know its that side, if it does not then you know your pump is pooched.

Great idea. I should have done this....

But instead... I've got the entire pump disassembled now. The bearings are actually in great condition and won't need to be replaced. The seal was shot (and I'm hoping it's the reason it wouldn't prime.) New parts in a few days and we'll keep our fingers crossed!

92SupraComp
07-24-2012, 11:02 PM
i t looks like piece #21 is a bit worn there. actually really worn compared to what the pumps in our 2 boats look like. also. i cant fully identify what pumps we have. how did you find out?

wotan2525
07-25-2012, 12:17 AM
i t looks like piece #21 is a bit worn there. actually really worn compared to what the pumps in our 2 boats look like. also. i cant fully identify what pumps we have. how did you find out?

Thanks! Just ordered brand new seals, snap-rings, washers and the cam. I figure as long as I've got the shaft knocked out, I can put it back together with new parts. Friend has a press in his shop that will put it all back together for me.

The G55-2 corresponds to the part # on the SkiDim website for a replacement pump. (A little hint -- you can't see a part number on their site until you add it to your cart. I think they do this on purpose so that you can't comparison shop.)

SquamInboards
07-25-2012, 11:32 AM
Thanks! Just ordered brand new seals, snap-rings, washers and the cam. I figure as long as I've got the shaft knocked out, I can put it back together with new parts. Friend has a press in his shop that will put it all back together for me.

The G55-2 corresponds to the part # on the SkiDim website for a replacement pump. (A little hint -- you can't see a part number on their site until you add it to your cart. I think they do this on purpose so that you can't comparison shop.)

Sounds like you've got a pretty good chance with the new seal.

On the skidim website, you get a PCM part # when you hover over the item # - it shows up on the bottom of your browser as a link to the item with. I tried adding to the cart and still couldn't get the Sherwood G55-2 or anything, what am I missing?

wotan2525
07-25-2012, 12:57 PM
I googled the PCM part number. RA057009. The results came up with a G55-2 which I then verified by photos is the only Sherwood in the G series that looks anywhere like mine. Most of them have the intake and output ports 180degrees from each other. The G55-2 has them both located side by side on the bottom.

Also decided late last night to change my order to the major rebuild kit. It was only $20 more to get the bearings and a new wear plate so I figured it would be money well spent.

DAFF
07-25-2012, 03:58 PM
I think the issue lies between the hull and the pump. Ever had a small crack in a straw ?The fluid will flow but it takes some effort. The same case with your pump. With the forward momentim of the boat it will always prime itself. No help no prime and it gets hot.

I would remove and replace the hoses plus hose clamps and inspect the other emements of the cooling system while there.

wotan2525
07-25-2012, 04:47 PM
I think the issue lies between the hull and the pump. Ever had a small crack in a straw ?The fluid will flow but it takes some effort. The same case with your pump. With the forward momentim of the boat it will always prime itself. No help no prime and it gets hot.

I would remove and replace the hoses plus hose clamps and inspect the other emements of the cooling system while there.

I'm sort of expecting that I'm going to rebuild this pump to the tune of a week off the water and $200ish out of my pocket... and then find a split hose on the intake side when I go to reinstall.

That's just how things work.

But -- I've planned for that. The waterpump was overdue for service anyway. I'm going to justify my money and time off the water with that logic instead of seeing red and throwing wrenches.

I declared 3-years ago that there wasn't a nut/bolt/bearing/bushing/knob/switch/wire/fitting/connector or surface that I hadn't touched in this boat. But... new things keep coming up that surprise me! Who knew that the waterpump was this complex?

Jetlink
07-25-2012, 04:49 PM
If you do see red, don't throw wrenches at anything red...that's my advice. It's always like that though isn't it? You fix something that truly wasn't broken to begin with. When that happens, I just shrug my shoulders and say, well, at least it won't need fixing/replacing anytime soon.

DAFF
07-25-2012, 05:24 PM
Ive been wrenching my whole life and see it all too often. Even at the high end garages. Sometimes the most simple elements are the most complex to understand and troubleshoot. I would expect over 20% of all repairs are done in vain just trying to thow parts at something to fix it. This holds true for some of the professionals too!!

See a simple test like Docdrs sugested would of resolved this problem quickly and 100% accurate. I'm not trying to rub salt in the wound but simpily trying to help the next person out which will be in the same situation.

Please rember this everyone.... Before you replace the part try to be certain it is the true issue. Hunches and feelings are not enough, they will just cost you $ down the road. Trust me there is always a test for diagnostics !!!

docdrs
07-25-2012, 10:04 PM
I always try to use the kiss rule first. The simple and easy things should always be looked at first then go for the more complex. We all like to see how long things will last be we need to keep in mind there are reasons to replace certain things regularly as they are usually the first to fail.

wotan2525
07-25-2012, 11:54 PM
Well just so you guys know, I did investigate all of the hoses before I started rebuilding the pump. Hose from intake grate to tranny cooler, tranny cooler, hose from tranny cooler to water-pump were all "suck tested" and seemed to hold pressure well. I exhausted almost every possibility before I undertook the pump rebuild. If it ends up being something else, I'll be sure to let you know.

In the meantime.... it's been JS550 season!

wotan2525
07-31-2012, 12:43 PM
Got my rebuild kit yesterday and spent about an hour last night rebuilding the pump. Wasn't very difficult but did need to use a pretty heavy-duty bearing press to press in the seal, press the bearings onto the shaft, and then press the shaft/bearings into the housing. Installed the new cam, new impeller and then put it all back together.

To say that it is slightly tighter than before would be an understatement. The old one was very easy to turn over by hand. The new one requires quite a bit of effort and you can actually feel it suck against your hand even when just turning it over by hand. I'm feeling more and more confident that I've fixed the problem!

Stand by until I reinstall it later tonight but (fingers crossed) I'm feeling pretty good about this!

wotan2525
07-31-2012, 11:42 PM
Rebuilt water pump developed enough pressure to collapse my garden hose (while the garden hose was on!!)

Took it out to the river tonight for a wet-test and it performed flawlessly. This mystery is solved.

To give you an idea of the hours on this water pump, the new cam was at least 1/4" thicker than the old one. Huge difference!!

92SupraComp
08-01-2012, 09:41 AM
awesome! glad to hear its working again! now you can enjoy your boat. oh. for replacement impellers. go with Globe Run Dry Impellers. they are made of silicon and the first one we bought over 15 years ago and we just replaced it for the heck of it. it sat in the pump for over 15 years. through the winters of NY and the hot dry summers of Texas with out ever being checked and its still in almost brand new condition after many incident of dry runs.

ngavchris
08-01-2012, 10:31 PM
Glad that worked out for you. There nothing worse than worrying about overheating your engine. Amazing that the pump was that worn. You would never know it from the pictures. I knew that mine was the culprit and that was my last resort. Enjoy the rest of the season.

SquamInboards
08-02-2012, 08:55 AM
How many hours do you have on that?

wotan2525
08-02-2012, 11:15 AM
No clue. Hour meter was at 600 when I bought it but engine had evidence it had been previously rebuilt so once I tore into it I doubted the hour meters accuracy. Hour meter quit working after my rebuild. It's now been about 8 years on that rebuild so I would estimate another 800 odd hours.

Water pump had been around a few times!

SquamInboards
08-02-2012, 11:46 AM
Definitely... besides just curiosity I ask because I'm sure mine's been around a few as well, and is less than perfect. With a heater inline, the engine is always a pain to get primed when it's drained, so I'm thinking that your solution would be a good thing for me to do, and could make priming much easier. Like you, I have no real idea how many hours were on my engine before me, but have about 600 more since I've had it.

suprasam
08-02-2012, 01:23 PM
Wotan, glad you found your issues. If you dont mind me asking, what was the cost of your raw pump rebuild? I am thinking about rebuilding/buying mine, but the cost of my pump from Indmar is 375.00 (OUCH). I don't have a press, which I think you said one was needed at some point. Is the rebuild a job the average joe can do for a lot less? I know around a motor, well at least enough to get myself in trouble, but with decent instructions I can manage my way through. Any help/advice would be appreciated.

wotan2525
08-02-2012, 02:24 PM
Best price I could find was $128 from Amazon. http://www.amazon.com/dp/B0006GIK9Q/ref=pe_175190_21431760_M2T1_SC_3p_dp_1

I'd double-check that yours uses the same kit, but I really don't think that the rebuild was that difficult.

Here's the Sherwood instructions: http://www.pumpagents.com/pdf/SherwoodPumps/G55-2.pdf

Here's my rundown of a quick and dirty how-to (I wish I would have taken photos.... some of this is confusing but once you dig into it, it all makes sense):

http://i.imgur.com/9kugk.png

1) Seperate shaft side and impeller side of water pump.
2) Remove wear plate (#7) and gasket (#8)
3) Remove snap ring (#11/15). Then slide off washer (#12) and seal seat (#13)
4) Use a gear puller to remove the pulley (#23)
5) Remove snap-ring (#16 closest to the pulley) -- This will allow the shaft/bearing assembly to come out.
6) Use a rubber mallet (or brass hammer) to pound shaft and bearings out from the impeller side.
7) Find something the same diamater as the seal (#14) -- This seal is press fit into the body, so insert something the correct diameter and pound this seal out towards the impeller. Be careful that you leave the snap ring (#16) inside of the body still.
8) Take the shaft/bearing assembly and remove the snap rings (#11) from each end.
9) Use the same gear puller and pull off both bearings. The spacer (#20) just slides on to the shaft.

The next couple of steps can be done with an arbor press and the right size sockets, or -- take the whole thing to the machine shop and let them do it. Would probably only be $20ish.

10) Press bearing seal (#14) into pump body.
11) Put the right-most snap-ring (#11) back on the shaft.
12) Press bearing on to the shaft until it hits snap-ring.
13) Install spacer and then press on the second bearing.
14) Install left-most snap-ring (#11) back on the shaft.
15) Press bearing/shaft assembly into the body until the right-most bearing bottoms out on the right-most snap-ring (#16). This is confusing looking at the diagram because it looks like those #16 snap-rings snap onto the shaft. They actually snap into the outside bore of the pump body.
16) Install left most snap ring (#16) -- Now the bearings are kept into the housing by the outside set of #16 snap-rings.
17) Reinstall the seal seat (#13), washer and snap-ring (#11/15).
18) Remove and replace cam (#21)

You can now install the wear plate, impeller and the paper and o-ring gasket. Put two halves of the pump back together. Shazam! New pump!

suprasam
08-03-2012, 11:22 AM
Wotan, thanks for that killer layout. I don't have a press or a gear puller plus it looks like this will be a little above my abilities. Maybe it's easier than it looks, but without the right tools I am sure I will be messing something up. So I guess I will be putting money aside and paying the 375 for a new one. Thanks for the help!

wotan2525
08-03-2012, 01:33 PM
No problem. I'd make sure you try and sell your old pump.... I think you can recoup at least a benjamin or so on eBay.

NorCalPR
08-03-2012, 01:49 PM
FWIW, I did the rebuild on my Johnson Crank Driven impeller pump using a vise, puller, hammer, and a couple drift pins/bars

Start to finish, it only took be about 45 mins. A press is overkill for these IMHO

chris young
01-27-2013, 12:10 AM
Hi Guys, I'm resurecting this thread.

My pictures to follow, I've been photo documenting my pump ordeal. Mine is (I'm pretty sure) a G20. Anyhow, I'm stalled at the pulley removal stage. I've drilled 4 holes in the pulley, put a cast iron flange on the back for support and bolted a puller to it and cranked it to the point of requiring a new pulley. I even milled a circle out around the shaft in case there was a retaining ring that I was missing. No budge yet. I think my next course of action is to cut the pulley off. There are several options for a 6" pulley with a 5/8" bore,(this looks exactly like the one on my pump, but I'm in Canada so the shipping is a no go.
http://www.tractorsupply.com/phoenix-steel-drive-pulley-5-8-in-bore-6-in-od-1185196

I've torn the pump down this far, so I'm not going back now, but it is frustrating. Someone else mentioned Skidim's price for the bearings being out of whack, I guess so. They should be about 5 bucks a pop, when I get a proper number for it I'll post it here for the next poor bastard who takes this job on. The NTN # is SC0228LU but their own web site doesn't recognize it, but it will be an easy bearing to find.

Wish me luck

Jetlink
01-27-2013, 12:27 AM
Chris, where in Canada are you? What major city is near you?

chris young
01-27-2013, 11:15 AM
I'm in Guelph, close to Toronto.

I've been trying to upload my pictures but haven't had much luck, I'll check the FAQ and figure out what I'm doing wrong. I want to post photos and progress so others can benefit from my pain. Good news is I've got 3 months to get it done so no hurry. BTW the bearings are available all over the place, seems to be a common bearing for trimmers and lawn mowers http://www.hyperparts.com/wc.dll?ctwp~getxref~1001~1003~1~probrand~1~Bearing ~SC0228LU. 7 bucks each.

Someone on planet nautique also posted the mechanical seal as a thrust bearing for starters, but I'd have to dig that up again. I'd buy the Sherwood major repair kit for the pump but it seems rather overpriced for what you get.

wotan2525
01-27-2013, 04:38 PM
The sherwood kit does seem to be overpriced but it's because of the brass pieces.

Upload your images to imgur.com or photobucket and then just paste their links in. The attachment system on this board is worthless.

chris young
01-29-2013, 02:37 PM
Well, I finally got the whole thing disassembled. I gave up on trying to pull the pulley, and cut it off. I had fully expected to find a pin or something holding it once I got it off, but, nothing. 30 years of being pressed on just held it in place. The rest I was able to get apart using my puller in various configurations without too much grief. I've decided not to replace the bearings, they're pristine, and to get the OEM from a bearing supplier would be 38 buck each, part of why the price on Skidim is so high. The really do cost that much.

I've ordered the minor repair kit from Sherwood, and I'm going to sandblast the castings and hone the bores before I put it all back together. Still haven't solved the replacement pulley yet.

Photos to be posted some day:rolleyes:

suprasam
01-30-2013, 11:19 AM
Chris, I haven't read the whole thread.....but I have a 351 PCM (86) and I have I believe the complete repair kit for the pump. I don't have it in front of me but I believe everything is there. I bought them because I was going to have my pump rebuilt, and I ended up finding a new one for a great price. If you want the repair kit and it will fit you can have it, just pay shipping. I will pull it out tonight and let you know exactly what I have.

chris young
01-30-2013, 09:22 PM
Wow that's cool Shane, the offer is much appreciated. I just ordered one through my local dealer and I don't feel right about cancelling the order, so I'm going to have to pass.

chris young
03-04-2013, 02:18 PM
So this may be one of the most boring posts on the site. but after searching the web for info on this pump, I discovered there isn't much, so I figured I'd post all the info I could provide for the next poor bastard who wants to take this on.

Ok, so the pump rebuild is almost complete, First of all, mine had no ID tag on it, so the exact model was not known. From all the pictures it is either a G20 or a G21. If yours looks like mine, regardless of this http://www.sherwoodpumps.com/FileAttachments/Marine-Distribution/en-us//Literature/MPG_G20.pdf there is no set screw, no keyway and no retaining ring holding the pulley on. This one http://www.sherwoodpumps.com/FileAttachments/Marine-Distribution/en-us//Literature/MPG_G21.pdf looks closer to my pump, just a pressed on pulley, but the picture shows a pulley with 3 large holes in it which mine did not have.

You can see how robust a puller I put on this thing and it wouldn't budge. Even backed with a cast iron flange and 4 holes drilled through the pulley into the flange, the pulley would not budge. I heated it and still no go, so since you have to remove the pulley to rebuild the pump, I ended up cutting it off. It didn't matter anyways, I had bent the pulley enough that it wasn't any good any ways.

Parts. The price for replacement bearings from Skidim is reasonable. I bought mine from an industrial supply house (NTN SC0228LU) and they were 38 bucks a piece. That is the exact bearing I pulled out. Sherwood calls it P/N 12211. If you search the NTN number, you will get a bunch of hits selling a replacement that is not the same bearing. At around 6 bucks a piece, it's tempting, but this is the water pump for my boat so I went with the NTN.

If you want the exact pulley that was on this one, it's cheap at TSC http://www.tractorsupply.com/en/store/phoenix-steel-drive-pulley-5-8-in-bore-6-in-od?cm_vc=-10005 The only difference I can see from the picture at least is that the replacement one is keyed. I couldn't find it in Canada, and shipping would have made it way too pricey so I bought a really high quality pully from the same supplier as I got the bearings from.

The pieces have been sanded cleaned polished and Painted are are ready for assy.


Pics so far
http://supragenious.imgur.com/all/

TitanTn
03-05-2013, 05:14 PM
Thanks for the writeup. I clicked the link for pictures, but it says that your pics are not publicly available. Maybe you need to change the security on them, or just paste the URLs here on the forum.

chris young
03-08-2013, 05:08 PM
Thanks, I've changed the settings. I tried your suggestion about just pasting, but the photo was HUGE and there's a bunch so I'll have to figure out how to resize them.

No pics of the restored pieces yet, I'll post them when I do the rest of the job.