Getting a Magic Chef furnace running

JRep1369

Hi,
 I'm new to the forum, and not in the industry, but my contractor recommended this site. I have an old Magic Chef gas furnace model G6A75D-11 that I'm trying to get running. We bought our place last year and it's in a building we're starting to use now, so I'm trying to get it running. When the gas company hooked it up last week, the pilot was clogged, so they could not light it. I got the pilot cleaned, replaced the thermocouple and it fired up, but with a delayed ignition, and the fan not coming on. I replaced the limit switch which fixed the fan problem, but it continues to have a periodic delayed ignition. Usually when the burners ignite after the flash, the front 1/2 of the right hand burner would have trouble catching, while all the other burners are fine. When the furnace does ignite normally all the burners catch no problem. I pulled the right had burner and vacuumed and blew air through it, but it didn't make a difference. I know it should be replaced, but right now we just don't have the money, especially with the electric heaters going. Below are pix of the pilot, the burners after a delayed ignition, and the burners after a normal ignition.
Any help is greatly appreciated.
Thanks
Joe

SuperTech

First thing I would check would be the gas pressure to the valve before and after ignition and the manifold gas pressure.  I'd also make sure the heat exchanger is safe for that furnace to be operated,  it's no good to you if it is poisoning you with carbon monoxide.  

Big Ed_4

I can see the problem on the last photo .. The flame is not fully lit though the right bridge .. needs to be cleaned and the gas pressure needs to be checked ...

JRep1369

Thank you @SuperTech, I don't know how to reply to your comment, so I figured I'd do it this way. As far as I know, no CO is coming from it, as the detector has not gone off, so my guess is the exchanger is ok. I have not check the pressure, so I guess that would be my next step. 
Thank again I'll keep you posted. 

JRep1369

@Big Ed_4 by bridge, are you referring to the piece that goes between the middle and end burners? If so, that was something that I was wondering about. 
Thanks

mattmia2

Check to make sure the orifices are clean as well. Whatever clogged the pilot burner may have also clogged the orifices. Just because the CO detector isn't alarming doesn't mean the heat exchanger is intact. Especially given its history, someone with a combustion analyzer that also knows what they are doing should take a loo at it to make sure the pressure is correct, that it is burning and drafting properly, and that the heat exchanger is intact.

JRep1369

Thank you @mattmia2, the drafting and such were things I was thinking about. I'm gonna post an update so the others who have helped can see where I'm at. This forum stuff is new to me, so I hope I do it right.