Koker Fire Died - Pusher Motor Dead?

Yesterday my Koker 160 furnace went out. I never had this happen before. I was hoping it was a thermostat issue, but even if the fire wasn't calling for heat, the stove should have maintained the fire on idle, right?

It seems like fresh coal wasn't being pushed in but I just want to confirm that is the issue before I move forward with figuring out why. When the stove is calling for heat (red and green lights on) should the pusher rod be moving all the time, or only once in a while? I watched it for some time and I didn't see any movement. I'm wondering if I just didn't watch long enough or if it's just dead.

Also, what role does that white wheel next to the rod play? Should that spin or something?

I'm not familiar with the Koker,but on my LL,the coal feeder only runs periodically.Is there a separate plug in for the feeder motor?If there is,plug it directly into an outlet.

Take a good up close look at the plastic white cam. It's hard to tell from the pic, but it looks like it may be deformed with one edge riding up on the metal plate - or the coal dust/dirt is making it appear so in the pic.

titleist1 wrote:Take a good up close look at the plastic white cam. It's hard to tell from the pic, but it looks like it may be deformed with one edge riding up on the metal plate - or the coal dust/dirt is making it appear so in the pic.

What does that cam do exactly? Looks pretty round and normal to me if I look at it up close.

the nylon wheel is the pusher, it is eccentric I believe. the pusher rod will only move when the block is being pushed or pulled. it kinda hesitates now and then. but only moves when the stoker motor/nylon cam is moving.

check your motor and make sure it's running properly. it's geared pretty low and doesn't turn very fast. the pusher will only move 1/4-1/2" if that depending on your feed screw settings.

do you have a manometer to check your draft?

Check your gaskets and draft make sure your fire wasnt burning too far back, or up towards the hopper. have you smelled sulpher or have any moisture in the hopper? If the fire burned back on the grate too far, it can melt the cam and it won't push.

I would clean it out real good, check the grate holes and seals and check your draft. pull the stoker motor and cam out and check it and make sure it's in good shape and the motor is turning properly.

Did you get your stove back up and running?

I had this issue last year. The cause was a blockage of some sort which I believe was a rock in my coal that prevented the push bar from moving back-n-fourth which in return caused the pin to sheer off that keeps the white cam in place on the motor shaft. So the sheer pin did what its designed to do.

Take a look at your pusher motor while the stove is calling for heat. If you see the small white fan running but the white cam is not moving then its a good possibility that the sheer pin needs to be replaced. Try to move the pusher bar back and forth to make sure its free from any obstructions.

Sorry for taking so long to follow up on this issue. With the weather pretty warm and a backup oil furnace (cheaper this year), this wasn't as much of a priority as it would be other years.

I believe the cause was as xpress23 mentioned. There is no pin holding the cam in place, so that must have broken loose. The pusher device seemed to be dealing with resistance, so I cleaned that out, so there's no coal or dust blocking it from moving back and forth freely. I'm just glad it didn't burn out the feed motor.

As a quick solution, I kind of just jammed the cam back on the motor shaft and even without the pin, it seems pretty firm. I'm sure it will work it's way off eventually again without the pin. Anyone know where I can get a suitable replacement for that or should I just get it from Keystoker?

Thanks for the update it will be a good reference for someone to check out on their stoker in the future!

Since it isn't a dire emergency, I would recommend getting it from Keystoker since anything else you put in may not have the same break point and damage the cam or motor itself.

Glad to hear you got back up and running. Give Keystoker a call and they will ship you a new sheer pin.

I just talked to someone at Keystoker. They said I could go to a hardware store and get a 1/8" steel spring pin, 1 1/4" long, there's no need to buy it directly from them.