Problems with Speed Control on Kirby Heritage II?

[heritageIIhd]

I recently completely rebuilt my 1986-87 vintage Heritage II.

This included:

New field, new armature, new bearings, brushes, switch, impeller, speed switch, etc.

Basically everything new except the housing itself.

However, when I turned it on, I noticed low suction. The speed control was working, as I later found out, because with the hose on, high speed was achieved, while low speed worked with the brush head.

After a few minutes of run time, the motor started sparking and I shut it down. I checked all of the wiring and everything is OK. However, it sparks and makes a strong burnt electrical smell now so I have mothballed it while I figure out what to do.

Shorted field? Shorted armature? Both were new, perhaps one was bad?

I hate to throw in the towel on this but I also hate to throw money at something that "doesn't suck" -- in an area where suction is a virtue, LOL.

 

[kirby519]

Sounds like it could be the motor carbons. Check those and see if they need to be reseated. Or they may need to be replaced if they didn't seat correctly when installed.

 

[eurekastar]

Try running it in nozzle mode with the belt off for 30 minutes and see if that doesn't help.  As already stated, the brushes may not be well seated.  Kirby motor brushes already are well shaped and shouldn't take much to seat them properly.  Did you use a seating stone?  That will do it quickly. 

 

[heritageIIhd]

Thanks for the tips. I did not use a seating stone. It looked as though the brushes were melting when it was running last! I do have a spare set of brushes. The armature where the brushes seat also appears to have some heat damage which was what led me to believe something was shorted.

 

[kirby519]

The discoloration is caused by the heat generated from the carbons not being seated. When properly seated you will see just a few blue sparks at the edge of the carbons. But not a fireworks show of yellow and orange sparks. Use a seating stone and that will clean up the communicator and get the carbons seated properly.

 

[eurekastar]

DO NOT run it on high until the brushes are seated properly.  Also, check to make sure you wired the speed switch correctly. 

 

[heritageIIhd]

Something is definitely amiss.

I checked the speed switch wiring, I must have reversed two of the wires. OK, no big deal, I switched them. I think it was yellow and white, or red and white.

I swapped in a set of new brushes. Same problem. Brush material went flying everywhere, arcing orange sparks, smoke. I shut it off. This was on low speed.

I must have fried something or it should have worked, right?

That sucks!

 

[eurekastar]

It sounds like you fried the armature when you accidentally switched wire.  I'd pull it and look at the brass segments on the commutator.  If they are melted, then it definitely is toast.  If you don't detect any melting, the next step is to test the motor field AND each segment on the commutator with an OHM meter.  I can walk you through that if you need help.  Don't run it anymore until you've done those checks or you'll also melt the insulation on the wires and something will catch on fire too.  If that happens, the smell is hard to get rid of.  With all that, it sounds like you're going to need a new motor field and armature. 

 

[heritageIIhd]

Do you have a way I can email you? I'd like to do the tests and see if I can salvage any of this -- I don't want to spend another @ 170 on field and armature if I can save one.

 

[kirbyclassiciii]

You can reach him at [email protected] if you wish to contact him.

~Ben