neo Posted April 23, 2011 Report Share Posted April 23, 2011 Hi Gents, I've got hassle with our 125 again .... Replace the impeller shaft (along with new bearing and seals) a few short months back but now she's weeping again. The shaft looks highly polished in the seal positions (early stages of scoring) so I have a couple of questions...... The bearing seem tight but any thoughts on what I might be missing that's made this go so soon? I read in a past thread that someone had sleeved a shaft (with brass?) and had success with that .... but I can't find that thread now?? Any ideas on how I could improve this water pump seal area? ... Better seals maybe? Best of balance. Neo Quote Link to comment Share on other sites More sharing options...
copemech Posted April 23, 2011 Report Share Posted April 23, 2011 Hi Gents, I've got hassle with our 125 again .... Replace the impeller shaft (along with new bearing and seals) a few short months back but now she's weeping again. The shaft looks highly polished in the seal positions (early stages of scoring) so I have a couple of questions...... The bearing seem tight but any thoughts on what I might be missing that's made this go so soon? I read in a past thread that someone had sleeved a shaft (with brass?) and had success with that .... but I can't find that thread now?? Any ideas on how I could improve this water pump seal area? ... Better seals maybe? Best of balance. Neo Eh, would think a biy of polishing on the shaft where the seals ride would be normal, long as there are no grooves that wont polish out. How much dirt found its way into the center section weep hole area? Don't know that you could find "better" seals. The fluids lube the seals, oil on one and coolant on the other. Coolant is supposed to have some seal lube additive in it, but I think I would assemble with a bit of silecon grease there in hopes to prevent it running dry. Sure you know which way the seals are oriented, but just in case, the open ends face the fluids. so the flats should face each other. Quote Link to comment Share on other sites More sharing options...
neo Posted April 24, 2011 Author Report Share Posted April 24, 2011 Hi Cope. Your'e always on the ball my friend It was late last nigh when I pulled the shaft out... took one look then dropped it all to one side in despair But the shaft polished up nicely this morning and has no scores even when I looked close up with a jewellers eye glass (x30). The seals still have the pink grease inside but there were black particles around the shaft hole, on the closed sides (facing towards each other), of both seals. I've also noticed that the black plastic impeller seems to have wear on the high points of the blades. As if it's been rubbing against the pump cover a bit. And maybe it's these plastic particles that's passed through the outer seal and damaged it slightly. As the leak was very slow. Don't know why the impeller would have been rubbing though. I checked all the shims and washers but they were all in the right places. Anyway I'm going to put it all back together with new seals. But I was wondering if Vitron seals would be a bit more robust? Best of balance. Neo Quote Link to comment Share on other sites More sharing options...
copemech Posted April 24, 2011 Report Share Posted April 24, 2011 Seals can be an odd thing. New seals,old seals, this seal that seal. Seems many times there is no rhyme or reason. I replace seals on old and new cars all the time, cannot see a thing. I was just in the manuals of the cars the other day and came accross the verse that stated that slight seepage and residue on water pump seals is normal!!!! In the shop environment, leaks are classified in three ways, seepage, weepage and leakage. Obviously in the last form, things are dripping. Somewhere in the middle, there is potential cause for concern, but in the first stage case, maybe not. Dust and dirt may pass. If it ain't broke, ---well? It ain't just me. These are acceptable warranty guidelines for the makers. Yet, in answer to your question, I see no advantage in the Viton in this application. As far as the impeller rub, you can ck rotational clearance to cover while apart, but doubt you find anything. Keeposted! MC Quote Link to comment Share on other sites More sharing options...
neo Posted April 24, 2011 Author Report Share Posted April 24, 2011 Well I never released that water pump failure was contagious .... Took my 250 for a quick spin yesterday...would you believe it drip, drip drip!!! This time the shaft is truly knackered (scored). Found a large rubbery bit in the chamber this time too... must have come from inside the hoses I think? I'm now down 4 seals, 1 shaft and two motorbikes down!! I can't buy any seals to get one bike working this long weekend, because of the Easter break. Would still be good to find that information on sleeving a shaft (with brass?) ....anyone?? Best of balance. Neo Quote Link to comment Share on other sites More sharing options...
copemech Posted April 25, 2011 Report Share Posted April 25, 2011 I seem to recall the shaft is about 8mm dia. One may polish out light grooving,but you probably want to keep things within a couple-three thousandths inch of original diameter for proper seal tension. Need hard metal for the seal surface, not brass. Making a precision sleve here is beyond my machine shop capacity, and takes precision work. I have an idea one might start with a piece of decent hard 3/16 id stainless pipe sold at hobby stores and hardware. The 5/16 od is near identicle to 8mm on the shaft. Quote Link to comment Share on other sites More sharing options...
mcman56 Posted April 25, 2011 Report Share Posted April 25, 2011 I have heard of wear sleeves but never tried them. They are very thin tubes that press on the shaft in the seal area. http://www.bearingservice.com/products/seals/wear-sleeves Quote Link to comment Share on other sites More sharing options...
neo Posted April 25, 2011 Author Report Share Posted April 25, 2011 Thanks for the information Mcman, I will ask down at the bearing shop but they look like they are hard to get hold of over here. I'm a bit concerned about what's causing this. Both bikes are on their original hoses (which look good on the outside) but the bottom rad and top Cylinder Head fitting have been on and off a few times in the past. The coolant on both bikes came out dead clean but would a water flush-out (in both flow directions) be a good idea? .... just tap water pressure. Best of balance. Neo Quote Link to comment Share on other sites More sharing options...
tony27 Posted April 26, 2011 Report Share Posted April 26, 2011 SKF make speedy sleeves but not below 12mm,you'd have to do it yourself http://www.skf.com/skf/productcatalogue/jsp/viewers/productTableViewer.jsp?〈=en&tableName=4_5&presentationType=3&startnum=1 Quote Link to comment Share on other sites More sharing options...
mcman56 Posted April 26, 2011 Report Share Posted April 26, 2011 When I replaced the seals on my 02 Sherco, the shaft had deep grooves worn into it so I replaced that too. It looked to me like soft steel that was not even polished. I saved the shaft with the idea of making one out of hardened stainless steel shaft material. It would be a lot easier than making a sleeve and the required precision diameter would come form the shaft material. It never failed again so I did not follow through. Quote Link to comment Share on other sites More sharing options...
spark Posted April 27, 2011 Report Share Posted April 27, 2011 When I had my 2001 Sherco I turned up 2 new shafts (1 as a spare) out of 2316 and had them nitrided. 2316 material has the advantage that it does not corrode because of the high chrome content, and when nitrided it has a very hard skin. I would not use brass, it is too soft and the seal will cut a groove in it even faster I would imagine. Quote Link to comment Share on other sites More sharing options...
neo Posted April 27, 2011 Author Report Share Posted April 27, 2011 Thanks for that Spark. I popped into an Oil Seals place today to see if I could buy the water pump seal. Got talked into buying seals that have only one lip on one side (open/spring side) because I they didn't have the double lip ones in stock....a bit like the one on their website. I wasn't keen at first but they talked me into it and told me that the other lip is just for dust and shouldn't be needed in this case....now I'm not so sure and don't want to score yet another shaft for the cost of a seal.....What's your thought on this? Best of balance. Neo Quote Link to comment Share on other sites More sharing options...
copemech Posted April 27, 2011 Report Share Posted April 27, 2011 Thanks for that Spark. I popped into an Oil Seals place today to see if I could buy the water pump seal. Got talked into buying seals that have only one lip on one side (open/spring side) because I they didn't have the double lip ones in stock....a bit like the one on their website. I wasn't keen at first but they talked me into it and told me that the other lip is just for dust and shouldn't be needed in this case....now I'm not so sure and don't want to score yet another shaft for the cost of a seal.....What's your thought on this? Best of balance. Neo You don't have dust, do you????????????? Not!!!!!! Quote Link to comment Share on other sites More sharing options...
shercogeezer Posted April 27, 2011 Report Share Posted April 27, 2011 My mate didnt fancy paying for a new shaft so I turned down his knackered waterpump shaft and made a stainless sleeve with a slight interference fit on it, heated sleeve, chilled shaft and pressed together then set up in lathe again and finished O.D of sleeve (turned and emery'd it). Reassembled with new lubricated seals and that's gotta be 18 months ago now and bike is riden regularly with no problems to report. Quote Link to comment Share on other sites More sharing options...
neo Posted April 27, 2011 Author Report Share Posted April 27, 2011 My mate didnt fancy paying for a new shaft so I turned down his knackered waterpump shaft and made a stainless sleeve with a slight interference fit on it, heated sleeve, chilled shaft and pressed together then set up in lathe again and finished O.D of sleeve (turned and emery'd it). Reassembled with new lubricated seals and that's gotta be 18 months ago now and bike is riden regularly with no problems to report. Perfect shercogeezer.... thats just what I wanted to hear Best of balance. Neo Quote Link to comment Share on other sites More sharing options...
Recommended Posts
Join the conversation
You can post now and register later. If you have an account, sign in now to post with your account.