EFM stoker won't heat up

Time to get dirty! Let the fire go out, empty the barrel, remove the large chunks ( m y guess) lift the pawls and turn the auger backward to empty it. manually crank fresh coal till burn pot is full. the usual clues are CO alarm and hot auger tube. I was using wet coal causing sludge caking. Now I control dust with a hood and shopvac. Sounds like a vintage unit, might be auger is too worn to supply enough fuel. Hope any of these help, Gary.

I would check behind the grates to make sure it is not built up plugging partialy the air to the fire.

I'm suspicious of the coal he's been burning. Even if you ran in different coal there could be a lot of muck clogging up the works if it was really dirty bank coal.
EFM's are designed to burn rice or buck. I generally stick with rice as it's easier on the auger and seals up the feed tube tighter than buck.

Problem solved, been awhile but we finally removed the fire pot assy and found the ring on the bottom of the pot where the grates sit against had a 1/4 inch crack thus allowing the blower air to enter the auger pipe and blow fumes up thru the hopper and not giving enough air to get a good flame and bring the unit up to temp, really not sure why or how it got cracked, however I convinced the home owner to use good coal and not the dirty inconsistent sized discount coal he had been buying. Had someone weld and grind smooth the crack in the cast iron pot, bought new grates and re-assembled the unit, fired it up and now all is fine, temp goes up nicely and no fumes from the hopper, this one had me puzzled as everything looked fine until we removed the fire pot and dis-assembled it and then could see the crack. And yes I know cast iron is difficult to weld but we had a guy who is a pro at cast iron welding do it, he works as a welder for a boiler maker company and welds cast iron on a daily basis at his regular job. Thanks for all the advice, hope no one else has a problem like this.

Thanks for the Return and Reply. Sure others can learn from your experience.

*****Never mind I see it was solved******Interesting. I'm having this same issue with my new DS SB200 except for the blow back into hopper sounds exactly the same..Ever remedy this and if so what was the deal? 4 ton in one month and water doesn't get above 140 when thermostats are calling for heat..