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Beans Maple
03-20-2010, 02:21 PM
Today my sihi pump started "squeeling" some while it was running. The vacuum level was down and a bit jumpy too. Can't tell exactly where the noise is coming from but the motor side bearing seemed warmer than usual and when I shut it down both side were dripping water. What is wrong with it and can it be fixed? Can I try tightening the nuts on the bearings? Do they have rebuild kits for these?

Whitfield
03-21-2010, 08:12 AM
Can you tell where the noise is coming from? Does the pump turn freely or does it drag if you try to turn the shaft by hand?

I use partial recirculation and frequently - more than once per season have one of my 3408's sieze up due to calcium build up in the pump. If you are using hard water you might pull off the flanges and take a look inside for calcium build up. I have cleaned mine many times by filling it with "CLR" or some similar product for cleaning lime from kettles, etc. I have thought of using phosphoric acid, but have avoided this for fear there might be brass parts inside which would be attacked.

My oldest pump had grease fittings - if yours has these grease might be an answer. I replaced these bearings with sealed units and the newer pumps came equipped with sealed bearing units. Bearings and packing are easy to replace. Sihi told me that it is not worth breaking down the pumps themselves, but I was at Lapierre Waterloo's facility in Quebec a couple of years back and they were breaking the pumps down and rebuilding them on a regular basis. Tightening the nuts on the packing follower may slow the water flow, but it will not likely address the squeeling - in fact it may make it worse as you will be tightening the seal between the packing and the shaft.