Pumps fcked

[Big Mick]

Ive been having issues with my brew pumps. Ive got 3 MKII pumps on a 3 vessel HERMS setup. Two of the 25kW guys on the HLT and LMT. And Ive got the 65kw on the BK for whirlpool / chilling / transfer. I never had an issue when they were set up horizontal, but I re-designed the setup and running them vertical made sense. Shortly after that one on the LMT and BK started running real loud and sseizing between uses. No issues at all with the HLT one. In runs quiet as every time. The 65kW one on the HLT is loud as fck. Never used to be. The LMT one is loud too. I took the whole thing apart, inspected, cleaned the bearings and regreased even though they were full of it. Can't diagnose any issues at all. The small pump on the LMT needs the housing to be removed to get it going like its catching or something. Sometimes I gotta run the pump while I re-install the housing just so I know its not gonna catch again.The bigger one actually needs to be physically unseized - gotta remove housing and rotor and turn the body itself if that makes sense. Its hard to turn it but once you break the seal its fine until the next day. Any ideas?

 

[wide eyed and legless]

Ive been having issues with my brew pumps. Ive got 3 MKII pumps on a 3 vessel HERMS setup. Two of the 25kW guys on the HLT and LMT. And Ive got the 65kw on the BK for whirlpool / chilling / transfer. I never had an issue when they were set up horizontal, but I re-designed the setup and running them vertical made sense. Shortly after that one on the LMT and BK started running real loud and sseizing between uses. No issues at all with the HLT one. In runs quiet as every time. The 65kW one on the HLT is loud as fck. Never used to be. The LMT one is loud too. I took the whole thing apart, inspected, cleaned the bearings and regreased even though they were full of it. Can't diagnose any issues at all. The small pump on the LMT needs the housing to be removed to get it going like its catching or something. Sometimes I gotta run the pump while I re-install the housing just so I know its not gonna catch again.The bigger one actually needs to be physically unseized - gotta remove housing and rotor and turn the body itself if that makes sense. Its hard to turn it but once you break the seal its fine until the next day. Any ideas?

Is there an O ring, or gasket between the body and the impeller casing? If its a gasket a trick is to use another gasket or thicker gasket material to keep the casing a bit further away from the impeller.

 

[S.E]

I never had an issue when they were set up horizontal, but I re-designed the setup and running them vertical made sense. Shortly after that one on the LMT and BK started running real loud and sseizing between uses.

It could be the orientation. Can you post a picture? I’m not 100% sure but I think the outlet is supposed to be above the inlet when the pump is vertical. When the pump is horizontal it doesn’t matter but vertical you may need to turn the head till the outlet is uppermost. I know it will work with the outlet lower but I’m sure I have read that it is supposed to be up.

 

[MashBasher]

You report your problem began when you changed orientation. Sounds very likely to be the cause.

If the pump is not fully primed (ie has a pocket of air caught in the housing) it will make an unholy noise as it cavitates. It’s possible the pump is still okay.

This guide is from March pumps, but applies equally to yours: A Short Pump orientation/mounting tutorial

You can test by fitting a tee and a second ball valve to the outlet that will allow you to bleed off any air that my be captured in there.

 

[S.E]

(ie has a pocket of air caught in the housing)

yep thanks, thats what I was trying to say. And possibly causing no lubrication and causing the seizure?

 

[MashBasher]

yep thanks, thats what I was trying to say. And possibly causing no lubrication and causing the seizure?

Glad that was useful. Yes, the pump will be running dry as Walter explains in his tutorial that is linked to above.