Taco LP series circ pump seals

[chillerguy81]

Good morning all,

Have a Taco BB1508 7.4 XXXXX circ pump 1975 vintage. Shaft seals had been leaking for quite awhile, finally got the ok to fix it. Tore pump apart and replaced seals as I have with quite a few of these model pumps, no big deal. After disassembly I noticed that the pump shaft beneath shaft sleeve had many galges and imperfections in it, probably from some previous yahoo trying to beat off the shaft sleeve with a chisel. Try cleaning up shaft and reassemble, what do you know water leaking between the shaft and sleeve. So I'm thinking about pulling the pump back apart and joining the shaft and shaft sleeve with retaining compound like you do with some other manufactures pumps. I'm hoping the retaining compound with fill in the voids in the pump shaft. Any one see a problem with this or have any other ideas? Thanks.

[DaveCR]

The sleeve is held in compression so it can't turn. I think silicone sealant would work just fine and it will be easier to disassemble in the future. "Easier" is a relative term as this series has to be the biggest PIA to work on.

The only LP I have left, a circa 1965 model, uses a copper crush washer to seal the exterior end of the sleeve. Does yours use the same?

[chillerguy81]

"The only LP I have left, a circa 1965 model, uses a copper crush washer to seal the exterior end of the sleeve. Does yours use the same?"

Yep sounds like the same deal. I didn't realize that the copper washer was suppose to seal the shaft sleeve, thats good info, I may have to take a closer look at that. Thanks.

From my experience with retaining compound it's not too bad to break loose. Just hit it with the mapp gas torch while applying pressure to the sleeve with a gear puller, works like a charm.

[chillerguy81]

DaveCR I read your post again and I think you answered my question. I wasn't sure if the sleeve was suppose to turn or not since you can't really see it with this pump. You said that the sleeve is held in compressor so it doesn't turn, that would make sense with the way the seal is constructed. In that case "gluing" the sleeve to the shaft would be bad because the sleeve would turn and tear up the inner part of the seal. I'm thinkin I'll have to try and repair the shaft with JB Weld or something and get the customer prepaired to order up a complete bearing assembly. If you have any service lit on these pumps I'd appreciate it. Taco's website has none, I guess since these pumps have been obsolete for a while.

[DaveCR]

What I meant was, because the sleeve is "squeezed" it won't spin on the shaft, it will spin with the shaft (which it needs to do). So, something as tough as bearing retaining compound isn't necessary to hold the sleeve in place. Retaining compound will certainly work and as you said it isn't all that tough to break down.

I'm in the same boat as you when it comes to any service literature on this series pump.

Good luck with it.

[BKS60]

Recently had the same problem on a hot water pump. After replacing seals it leaked up the shaft due to marring on the shaft. I pulled it back apart and put a small amount of silicone on the shaft and reassembled. Its been running fine for around 3 months now. Hope it continues to hold since the alternative is to replace the motor for a few small sratches.