high heat kills my march pump...ideas on a fix?

[CidahMastah]

Wanted to post about my experience as well. I contacted Mike at chugger and he asked me to send the pump back to him and they would repair/replace based one my comments. Very fast response, just as he was quick to get in touch with me and answer questions when I bought the pump the first time around. I send it earlier this week and will post back when I hear back or receive the repaired/replaced pump from chugger.

Thanks for the help Mike.

 

[runningweird]

ok so, post update.

I got the 815 impeller, new oring and a new thrust washer in the post today.
You can see the smaller impeller on the right, which Mike was kind enough to send me from Chugger Pumps, and the larger 815 impeller on the left. The thrust washer that was on the pump was kind of loose - but the new one is snug and fits nicely. I should note that the new pump impeller pushes a lot more water than the smaller impeller - a lot more. I think I will have to dial back on the valves so that I don't get channeling in my grain bed when I do my next mash
anyway- some pictures

here is the assembled pump head

So I boiled water( take that home ec teacher) and started recirculating. same old story. A loud squawk soon after re-circulation starts.


I have kept Mike updated - He said he sent me out a new pump back today - I guess we will see if that fixes the issue

 

[runningweird]

I got the pump back plate in the mail today - no dice. The boiling water killed the thing in the same short time period. So, Mike said ship the thing back to us and will fix it or replace it.

Gotta say I am liking chugger pumps company more and more.

 

[scubakevdm]

There's some deformation on the case sealing surface at the four o'clock position. Did the neighbor dog bite the pump too?

I'm guessing you've checked for especially shiny patches or other indications of uneven wear?

 

[runningweird]

There's some deformation on the case sealing surface at the four o'clock position. Did the neighbor dog bite the pump too?

I'm guessing you've checked for especially shiny patches or other indications of uneven wear?

I noticed the scratches there as well - I assumed the last owner dropped it.

but no, the only dog in my garage has been another neighbors geriatric beagle.

 

[scubakevdm]

Got any plastiguage?

Sure seems like a heat expansion thing to me, maybe combined with an alignment issue. What's the torque like on the backplate bolts? Is there a gasket? I sure would like to plop a blob of plastiguage on the end of that shaft and get an idea of what the Gap is cold. I'm not familiar with the units.

 

[runningweird]

nope what is it? how might that help?

 

[scubakevdm]

http://www.plastigaugeusa.com/how.html

Kind of an atypical application due to the small size of the shaft, but it would give you an idea of what your shaft end is doing.

Now that I look at the pump again, I see that the shaft seems to be stationary. If the tolerance between the magnet part of the impeller and the I.D. of the bowl part of the backplate are tight, and that shaft was out a hair then the metal expanded, I wonder if they would rub.

 

[scubakevdm]

That kinda begs the question, "Do the marks on the sealing surface that led you to believe the previous owner dropped it seem to be in places where they could only be if the backplate was removed when the unit was dropped?"
If so the shaft could be slightly misaligned and the misalignment aggravated by the expansion could be enough to stop the impeller.

 

[CidahMastah]

Got my new pump in the mail on Friday - sick customer service for sure. Will post back when i get a chance to try it out!

 

[Irrenarzt]

I think most all 809/815 pumps will suffer when boiling temperatures are used. The magnets cannot handle boiling temperatures and lose coupling, therefore you lose pumping capability.

Every one of them I've seen suffers from magnetic decoupling when boiling temperature liquids are pumped.

 

[scubakevdm]

Wow! That sucks. I did not know that. I was on the verge of getting one too. Maybe I'll try a peristalic pump.

 

[RoadKing]

I run my 809 during boil without any problems.

 

[runningweird]

I run my 809 during boil without any problems.

I think lots of people have pumps that work well for them - something about this one - a march body and a chugger head just doesn't mesh apparently.

Hopefully Mike at Chugger will be able to sort it out - I need to brew more beer.

 

[CidahMastah]

I think there are a lot fo variables too. Pick up tube location, electric heat vs propane, obviously the restriction in your feed line to the pump etc. I can run my march during full boil no sweat on my rig.

 

[WalterAtMarchPump]

I think most all 809/815 pumps will suffer when boiling temperatures are used. The magnets cannot handle boiling temperatures and lose coupling, therefore you lose pumping capability.

Every one of them I've seen suffers from magnetic decoupling when boiling temperature liquids are pumped.

The magnets actually can handle temps up to 250*F before loosing magnetism when turning at these higher speeds. The issues for most at boiling temps is that you are sucking the bubbles that are being made right off the bottom of the pot and in to the pump and causing it to cavitate. If you take a pot of water and boil it, you will see bubbles forming on the bottom way before they reach the top.
We actually have a customer that uses these very same pumps but with a special motor that turns at 1000rpm and they transfer hot oil at 303*F without issue.

 

[MalFet]

The magnets actually can handle temps up to 250*F before loosing magnetism when turning at these higher speeds. The issues for most at boiling temps is that you are sucking the bubbles that are being made right off the bottom of the pot and in to the pump and causing it to cavitate. If you take a pot of water and boil it, you will see bubbles forming on the bottom way before they reach the top.
We actually have a customer that uses these very same pumps but with a special motor that turns at 1000rpm and they transfer hot oil at 303*F without issue.

That was my hunch about what is going on. Any tips on a solution?

 

[WalterAtMarchPump]

only thing you can realy do is cut the heat when you reach full boil and turn the pump on as soon as the bubbles stop. Other then that i'd say for those that dont have any problems to post up a pic of the inside configuration of the pot you are boiling in ans see if theres anything common between them that you can incorporate into yours.
It may be as easy as shifting the pot on the burner so the pickup is as far away from the heat source as possible so you are not pulling the bubbles into the pumps...

 

[Irrenarzt]

Do you have a curve showing magnetic loss vs temp for your magnets? I bet cavitation is part of the problem but it also seems like the magnets are going somewhat slack as you can hear a tone deviation that sounds to me like decoupling at higher temperatures. Either way, it's a phenomenon I don't like. Luckily it's not a huge problem for me as I only recirc boil for 15 minutes to sanitize my plate chiller. Once I'm in whirlpool, the heat is off and it's not a problem.

 

[CidahMastah]

That was my hunch about what is going on. Any tips on a solution?

In my experience I did much better with the pump when I:
1. put my dip tube on a 90 and right up against the kettle side wall.

I have an electric kettle, so the majority of bubbles from the boil get generated at the element location (which is why I moved my dip tube to the sidewall location to begin with).

I too only recirc. during the boil for 10 minutes to sanitize the pump, etc.

 

[WalterAtMarchPump]

Do you have a curve showing magnetic loss vs temp for your magnets? I bet cavitation is part of the problem but it also seems like the magnets are going somewhat slack as you can hear a tone deviation that sounds to me like decoupling at higher temperatures. Either way, it's a phenomenon I don't like. Luckily it's not a huge problem for me as I only recirc boil for 15 minutes to sanitize my plate chiller. Once I'm in whirlpool, the heat is off and it's not a problem.

I don't have a curve to post up, but i copied this our magnet supplier once gave us a while back:

****************
Up to about 840F, changes in magnetization are largely reversible, while changes between 840F and 1800 F are re-magnetizable. For all Ferrite magnets, the degradation of magnetic properties is essentially linear with temperature. At 350 F, about 75% of room temperature magnetization is retained, and at 550 F, about 50% is retained.
****************

There's allot of factors that come into play with pumps and magnets when dealing with heat situations:
how thick is the fluid?
how much restriction is on the inlet side of the pump?
what size line is on the inlet/out of pump?
head height it has to pump up to?
RPM of motor?

 

[runningweird]

All I really want to do is recirculate boiling wort through my plate chiller to sanitize it, and as far as the bubbles in the line go I doubt that is the issue - I use an electric element a good distance from where the pickup tube is located.

Walter at march reached out this morning to help me diagnose the issue as well, he offered to send some replacement parts but I had just put the pump in the mail to chugger. Nice to see that these companies do really care about their products and their customers.

Will update as more info becomes available.

 

[runningweird]

Just got an email from Mike, along with a video of the pump working while pumping boiling water - Based on customer service alone, again for something bought secondhand, I will not hesitate to try one of their new pumps when I expand my brew setup.

http://www.youtube.com/watch?v=YaPYpycwEck&feature=youtu.be

Fantastic, Can't wait to get it back and brew something, or perhaps I will use it to sous vide some spare ribs....so many possibilities.

 

[scubakevdm]

Sweet. Did he say which parts he changed?

 

[runningweird]

Got the pump back in the mail today, it is currently pumping away while the kettle reaches boil temps. I just sent an email to Mike asking what parts he replaced, it looks like there is a new head on the unit. I will post back when I hear from him and after the pump pushes boiling water for a while.

 

[CidahMastah]

Got the pump back in the mail today, it is currently pumping away while the kettle reaches boil temps. I just sent an email to Mike asking what parts he replaced, it looks like there is a new head on the unit. I will post back when I hear from him and after the pump pushes boiling water for a while.

Cool - I have yet to try the pump I was sent, but will let people know if it remedies the problems. Would like to know the replaced parts as well for future reference.

 

[runningweird]

nothing back from Mike at Chugger yet, but the pump just pumped boiled water at a great rate for almost an hour. I think chugger fixed the problem - it looks like the head had to be replaced but I am not quite sure.

So the problem is FIXED!

 

[chuggerpumps]

I did not have time to troubleshoot this particular pump but I Know Ian said he had a Mach Pump and then bought an original model Chugger Head second hand from someone. So I was uncertain of what happened with this pump. Glad I could help

nothing back from Mike at Chugger yet, but the pump just pumped boiled water at a great rate for almost an hour. I think chugger fixed the problem - it looks like the head had to be replaced but I am not quite sure.

So the problem is FIXED!