Frozen March Pump - not the head

[Kayos]

Running a single tier 2 pump direct fired, recirculated setup. Both March pumps are not turning anymore after a fairly major boilover (don't ask!). I took off the heads and cleaned them, but they still are stuck. Even with the head off, the shaft won't spin under power. I tried to disassemble the pumps, but it looks like the only part I can take apart is the head. I'm sure I gunked up the entire unit and need to clean it all out.

Thanks for your help!

 

[microbusbrewery]

You might want to reach out to Walter at March (https://www.homebrewtalk.com/members/walteratmarchpump). If anyone would know how to clean them, it would be him.

 

[gandelf]

Look through the cooling slots and check if wort has gotten into the motor windings and armature? If so, take it apart and rinse it out; then let it dry very well.

 

[WalterAtMarchPump]

I replied to your PM but in case any others have this same issue:
First thing i would do is remove the pump head and try and turn the motor over by hand. (remove the 4 phillips head screws and not the flat heads holding the motor bracket on.)
If it turns but its rough or hard to get it to turn, then i would then go and try and find some contact cleaner in a spray can from an electrical supply store like radio shack.....spray it all down....put some 3-in-1 oil down the oil holes on the ends of the motor (look for the arrows on the motor label) and then let it sit for a day or two to let the contact cleaner fully evaporate before trying to turn it on.

If you cant get it going from the above then you have nothing to loose at this point since the motors may be toast......i would get a bucket of hot soapy water and dunk the motor in there while turning it over by hand....let it soak for a few minutes, swirl it around.....rinse with clean water....then spray it down good with WD-40 and oil the bearings with the 3-in-1 oil.....then throw it into an old sock and place it into a bucket of rice and let it dry out for a good week or so....you may want to change out the rice mid week just in-case...

 

[BadWolfBrewing]

The march pumps are just induction machines, so you should be able to get the rotor out of the stator without damaging it. The bearings are probably press-fit, but a little gentle tapping should get the rotor out one side.

If you get it working, you'll definitely need to re-oil everything.

I'd be surprised if the motor was toast. Induction machines are about as simple as a motor can be (unless you are trying to solve the governing differential equations, in which case they are the most complicated). The windings should be pretty well varnished, so there probably wasn't electrical damage. Were they running during the boil? When you tried to run them again, was there a burnt smell?

 

[WalterAtMarchPump]

What BadWolfBRewing said is correct as they are simple motors. These motors potentially have two different kinds of bearing in them....for the most part they have sleeve bearings and that's why they have the oil holes on the sides....some also come with sealed ball bearings so those should hopefully not get anything inside unless they were seriously submerged.
Its not very hard the get these motors apart....on the back side these are 4 clips you can pop off with a flat head screwdriver and the cap comes off....watch the small plastic spacer washers as the sometimes fall off...you need them
To get the rotor out of the motor you need to take the motor bracket off and the drive magnet....again there are some plastic spacer washers on the front side of the rotor as well...if you clean everything off/out....just be careful around the sleeve bearings as there is an oil soaked packing material in there that you can wash out easily if you are too aggressive....then spray it all down with some rust inhibitor like WD-40....oil the bearings...let it all dry..reassemble and test it out.

 

[Kayos]

There is a power hum when I plug it in. There is no electrical 'burn" smell. I've taken off the head, and popped off the vent in the back, but I can't get the case off to clean the actual motor. I'm going to get contact cleaner today and 3 in 1 oil.

When I rotate the shaft by hand, it seems difficult to turn, but not really "gunky". It does feel like they would be too much for the motor to turn though.......

After I do all of this if they're still acting up I'll post a youtube vid.

 

[WalterAtMarchPump]

Sounds to me like the motor got a good "HIT" and knocked the alignment of the rotor off.....now its too close to the filed windings and the magnetic field is pulling it too close to one side and locking it up.
I wont rule out the gunk internally as a possibility though from what you've been telling us so far.
Does the motor turn easy when no power is applied? or is it tight all the time?

 

[BadWolfBrewing]

Wait... field windings? This is a wound field synchronous machine?

 

[WalterAtMarchPump]

no i just refer to the coil windings as such....habit..
These are simple shaded pole motors

 

[Kayos]

Sounds to me like the motor got a good "HIT" and knocked the alignment of the rotor off.....now its too close to the filed windings and the magnetic field is pulling it too close to one side and locking it up.

Does the motor turn easy when no power is applied? or is it tight all the time?

Can I fix this - the alignment of the rotor?

It feels tight when turned by hand without the power on, but I have no experience with doing this prior to it not working.

 

[WalterAtMarchPump]

Hard to say without looking at it....if you want to send it back here to the factory we can take a look at it for you. Give Wayne Frantzen in service a call and he'll give you an RGA# for tracking purposes