Harmon P61 Feed Auger Noise

[Battenkiller]

Hi, folks, BK here. Been a while since I've posted as I no longer burn wood and haven't had any problems with the P61 until yesterday.

Started getting a loud squealing sound every time the auger fed pellets. Cleaned the burn pot all around the auger (wasn't much of anything there). No change. Cleaned the fines box (maybe a half teaspoon in there). Took the back off to access the auger motor. Ran it in "test" mode while I looked at it. The main auger bearing seemed to freeze in place for a second, at which time the squealing sound was heard.

I sprayed the bearing with lithium grease, then gave it a squirt of WD40 to help draw the grease into the bearing. Worked like a charm.

Not only is the squealing sound gone, but so is a low rumbling sound that happens just before you hear the pellets drop. That sound has bugged me since we inherited this stove 3 years ago.

So, now I'm wondering, should I replace the bearing or wait and see if the squealing noise starts again? The fact that the rumbling noise is gone now makes me think that the motor may have been under extra load the whole time we've been here. I thought it was just the way the stove sounded, especially after a local service place told me it was probably just internal resonance. Now that appears not to be the case.

 

[Bioburner]

I would get on the bearing issue ASAP. It could spin again at any time .and mess up the holder or worse by the time it makes more noise and the rotor starts rubbing ruining the motor and you can guess ruining some bigger $$$.

 

[Battenkiller]

So, the sound is coming from the bearing housing spinning on the shaft instead of the bearing turning, is that right? Is the bearing a press fit on the shaft?

In other words, will I need to remove the auger from the stove to change the bearing? I have it all put together again so I can't look at it right now.

 

[BrotherBart]

Whoa! Welcome back BK.

 

[Battenkiller]

Whoa! Welcome back BK.

Hey, BB, how's it going? Hope you are well, but please, stop sending all this dang snow up the coast, OK? We got plenty already.

 

[BrotherBart]

Doing any scientific testing of pellets?

 

[Battenkiller]

Doing any scientific testing of pellets?

Yup. Found they don't burn worth a hoot when the MC is above 25%.

 

[Dale K]

Hi, folks, BK here. Been a while since I've posted as I no longer burn wood and haven't had any problems with the P61 until yesterday.

Started getting a loud squealing sound every time the auger fed pellets. Cleaned the burn pot all around the auger (wasn't much of anything there). No change. Cleaned the fines box (maybe a half teaspoon in there). Took the back off to access the auger motor. Ran it in "test" mode while I looked at it. The main auger bearing seemed to freeze in place for a second, at which time the squealing sound was heard.

I sprayed the bearing with lithium grease, then gave it a squirt of WD40 to help draw the grease into the bearing. Worked like a charm.

Not only is the squealing sound gone, but so is a low rumbling sound that happens just before you hear the pellets drop. That sound has bugged me since we inherited this stove 3 years ago.

So, now I'm wondering, should I replace the bearing or wait and see if the squealing noise starts again? The fact that the rumbling noise is gone now makes me think that the motor may have been under extra load the whole time we've been here. I thought it was just the way the stove sounded, especially after a local service place told me it was probably just internal resonance. Now that appears not to be the case.

I had the same thing happen to my Harman P68 last year (my 6th year with the stove). Drove me nuts. I thought it was the auger bearing. I finally emptied my pellet hopper cleaned out all the dust and blew out the auger chamber with compressed air. The squeal was gone. I had to do this once again this year. When I told my dealer about my findings he suggested that I run the stove out of pellets occasionally and blow out the auger chamber.

 

[Battenkiller]

I had the same thing happen to my Harman P68 last year (my 6th year with the stove). Drove me nuts. I thought it was the auger bearing. I finally emptied my pellet hopper cleaned out all the dust and blew out the auger chamber with compressed air. The squeal was gone. I had to do this once again this year. When I told my dealer about my findings he suggested that I run the stove out of pellets occasionally and blow out the auger chamber.

Interesting. I'll do that next time I let the stove run out of pellets.

I'm pretty sure it's the bearing in my case because I could watch it stop turning for a second and that's exactly when it would squeal. Anyway, it started again just a few hours after I sprayed it with lube, so I'm getting a new bearing tomorrow and putting it in. I was just hoping it'd hold out until this cold snap passed.

 

[Dale K]

Interesting. I'll do that next time I let the stove run out of pellets.

I'm pretty sure it's the bearing in my case because I could watch it stop turning for a second and that's exactly when it would squeal. Anyway, it started again just a few hours after I sprayed it with lube, so I'm getting a new bearing tomorrow and putting it in. I was just hoping it'd hold out until this cold snap passed.

I had the same thing. I lubed the bearing, took off the plate that holds it on the auger and turned the auger by hand. I could feel the resistance. It wasn't until I blew out the auger that the squeal ended.

 

[Battenkiller]

I had the same thing. I lubed the bearing, took off the plate that holds it on the auger and turned the auger by hand. I could feel the resistance. It wasn't until I blew out the auger that the squeal ended.

Well, I guess I'll give that a try now. Certainly the easiest thing to try, and I can't get a bearing until tomorrow at the earliest. I doubt it's ever been done by the guy I bought this place from, and I know I never did it. At least it'll be done. Thanks for the info.

 

[Battenkiller]

OK, I tried everything suggested and a few other ideas I had. Nothing worked. Too much snow in the drive to get out to the stove store. Lady BK had a snow day today, so she decided to take a look see and she fixed it! Inside the fines box there is a reciprocating plate with a slot in it. It has another plate that goes through the slot, and there was rust at the contact points of these two plates (see arrows in photo). She sprayed it with WD 40 and the squealing sound stopped instantly. So I mixed up some grease with powdered graphite in it and had her paint the surfaces with an artist paintbrush. Looks like some damp pellet dust must have laid in there for a while, causing the rust to build up. Had a big problem with that this year after buying two tons and letting them store them at Home Depot. They left a partial pallet out in the heavy rain we got after the holidays without adequate cover, and many of the bags got wet. I did my best to be on the lookout for damp or swollen pellets/excessive fines, but apparently a few bags got past me. Damn Depot wouldn't even take them back because I had "opened them". Now, how the heck am I supposed to know they're bad if I don't open them?

Anyway, hope it lasts, but it's a quick and easy fix if it returns. Kudos to the lovely Lady BK for being smart enough to figure it out.

 

[Dale K]

Here's hoping that you found the cause and that your problem has been resolved. Cheers!

 

[Battenkiller]

Here's hoping that you found the cause and that your problem has been resolved. Cheers!

Thanks, Dale. Come spring I'm gonna go over this thing with a fine tooth comb. Seems like they always gotta fail during the worst part of winter.

 

[elevenMracing]

My P68 started squealing like a stuck pig everytime the auger turned yesterday, enough that I shut it off and switched over to my LP heater for the night because I was getting a headache from the noise. I debated pulling the auger assy apart for a good cleaning, decided to try the graphite trick first and I'm glad I did because it stopped the nosie dead in it's tracks. I emptied out the hopper completely, mixed about 2-3 cups of pellets with 6.5 grams of graphite in a small container until evenely distributed (pellets turn grey), dumped mixture into hopper, topped off with a few handfuls of 'untreated" pellets as to not shortchange the startup cycle, turned stove on, problems solved! Refill hopper and get back to work on the racecar!