My first rebuilt water pump

moddy

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This thread has caught the attention of moddy! I found an unusual size spot of coolant under my "91 ST1100 today. Cheapest price for a water pump is the before mentioned 240.00 ish.
If I can rebuild my pump for $50 bucks, I am going to do it. I am unemployed, so I have more time than money, I can weld too.
Glad I found this thread. Over the last few years I was led to believe there just wasn't a less expensive way. Thank you for putting this together.
 

moddy

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You found a new one available for a '91'?

as they are slightly different than all other years.
A new one what? Water pump? Having recently done a lot of searching, I think I know better that a 1992-1995 water pump will work rather than knowing I found a '91 specific water pump for sure.

Knowing the ST1100 that has been repaired was a '98 model, I might need to collect some more information before I order donor water pumps.
 

John OoSTerhuis

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Additional note: a 96-02 water pump can be fitted to 91-95s, but you have to remove the oil cooler and replace the Water Pipe and Oil Filter Bolt parts with the later year models'. It's been done. The ST had the 40amp alternator upgrade done on it. IIRC, his reasoning was the extra oil cooling was not needed when the old oil-cooled 28amper was replaced by the air-cooled 40amper (like all the 96-02 40amp equipped models without an oil cooler). FWIW

John
 

moddy

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In fairness, I need to explore exactly where the leak is coming from first, though I would like to do the automotive water pump transfer just to do it. I replaced fuel, coolant hoses and timing belt 18 months ago, so I have automatically assumed my water pump with 75k is ready for refurb. Thanks for the information. I will be able to pull it apart for inspection after this coming weekend.
 

moddy

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This is probably my ten thousandth lesson in not assuming something too soon. I came home, in the dark, a perfect time to be inspecting a leak but found a slightly larger puddle. I followed a streak on the inside of the cowling up to the radiator hose near the filler cap.
I'll get to do a water pump rebuild one day, it's just not going to be that soon after all.
20160913_203324-1.jpg
 
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It definitely was ready for a rebuild, Doug !! :)

BTW, The water pump seal "weep" hole was completely blocked with debris, too. I had to ream it out with a long drill bit.

EDIT :

And FYI : According to Kellogg Automotive ( water pump rebuilder ) it is normal for a water pump seal to "weep" somewhat. Not drip antifreeze, but weep antifreeze. That's the purpose of the weep hole. It prevents fluid build-up so the water pump bearing is not contaminated with fluid.

I remember that someone mentioned that this is also stated in the ST1300 service manual. So if you are ever checking or replacing your timing belt and notice some residue at the outlet of the weep hole don't be too concerned.
Have been reading the water pump refurb posts with great interest as I may be about to refurb mine. The weep hole or tell-tale hole (this side of the pond) , I thought was to give you early indication of a failing seal, hence the term "tell tale" . But I can see your reasoning for the weep hole drilling to be an avenue of escape, preventing bearing contamination and ultimately early failure...thanks for the insight......every day is definitely a "school day" when it concerns these ST's . Kind regards Dave........think my post has went to the wrong page?[/QUOTE]
 
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Dave, your post is readable, but you deleted the closing square bracket in the [/QUOTE] so your reply is in the part you wanted to quote instead of being a separate entry below the quote. Put the ] back in and it should look correct, I suspect this is what you meant by "my post has went to the wrong page?"
 
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Dave, your post is readable, but you deleted the closing square bracket in the
so your reply is in the part you wanted to quote instead of being a separate entry below the quote. Put the ] back in and it should look correct, I suspect this is what you meant by "my post has went to the wrong page?"
[/QUOTE]
Thanks for your help regarding my post :) you are exactly correct, kind regards Dave
 
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If you rebuild your pump, it's not that difficult of a job to accomplish, BUT ....... be very careful when pressing out the old bearing & shaft. It's easy to crack the water pump housing if you aren't careful. Try heating the area with a propane torch first to help break the corrosion free and support the housing the best you can in the press.

Don't ask me how I know about this.
 
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Jim Van
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The missing tangs were because I brain farted and forgot to change my coolant for a long time (8-10 years maybe, not really sure, I didn't write it down the previous time). The rest of the pump was more or less OK when I changed it out at timing belt change time (not leaking anyway, and the bearing turned by hand but seemed a little stiff). Then it sat for two years on the garage floor, and before I sent it to Jim I noticed the bearing no longer turned.
Time goes by fast - too fast the older you get, BTW.

I just had my septic tank pumped. I thought it had been 3 years since it was last pumped. The septic guy checked his records and told me it's been 6 years already.
 

Trapperdog

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Time goes by fast - too fast the older you get, BTW.

I just had my septic tank pumped. I thought it had been 3 years since it was last pumped. The septic guy checked his records and told me it's been 6 years already.
At least we know you’re not full of $#!t now. :D
 
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I just had my septic tank pumped. I thought it had been 3 years since it was last pumped. The septic guy checked his records and told me it's been 6 years already.
I have mine pumped on years that are divisible by 3 so I can easily remember when it needs it. Probably doesn't need to be pumped that often, but given the cost of replacement vs. pumping too often I choose pumping too often.
 
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If you rebuild your pump, it's not that difficult of a job to accomplish, BUT ....... be very careful when pressing out the old bearing & shaft. It's easy to crack the water pump housing if you aren't careful. Try heating the area with a propane torch first to help break the corrosion free and support the housing the best you can in the press.

Don't ask me how I know about this.
Thanks for the advice...waiting for replies regarding the refurb parts, but still to remove both cylinder heads and assess the damage Kind regards Dave
 
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Time goes by fast - too fast the older you get, BTW.

I thought it had been 3 years since it was last pumped. The septic guy checked his records and told me it's been 6 years already.
Sounds to me like Doug's old water pump brought a virus with it. Forgetting seems to be contagious.:rofl1:
 
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Thanks for the advice...waiting for replies regarding the refurb parts, but still to remove both cylinder heads and assess the damage Kind regards Dave
Got the wp refurb kit, followed the instructions......but......even heating with a torch, and supporting as close to the pulley as possible, the bearing/shaft pushed down a small amount until the impeller blades touched the casing, then the casting cracked along a contour line, was being REALLY careful too! Have another wp on the way but will still have to do the refurb (this time will cook it at 180 deg C and put additional heat on the impeller with a torch at the press). The wp arriving is missing an outlet for the oil cooler but the casting is the same so reckon it can be CAREFULLY drilled out and tapped to accept a hose connection ( bit of lathe work required) . Just need a working water pump to begin the rebuild :)243391
 
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