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tucsonjwt · 12-06-2014, 11:42 PM

They look like the champion plugs I just replaced - same thing, all carboned up.
Mine was running very rough with some black smoke on start up. I changed the plugs and all is well. I think the carbon is from running too rich. I used Champions because they were free with a rebate. I will go with AC 44RT when I run out of Champions. Rich running would be consistent with a stuck choke. Unless you just replaced plug wires also, I would install a new set of Belden plug wires from NAPA also.

In my case, I only run my 454 in town on short trips, so that contributes to carbon build up. I usually replace my plugs every year, and that is only 2-3,000 miles or so. I am going to try some BG 44K and see if that helps.

12-06-2014, 11:42 PM	#12
tucsonjwt Registered User Join Date: Jul 2007 Location: Tucson, AZ Posts: 3,198	Re: Misfiring after installing new carburetor. They look like the champion plugs I just replaced - same thing, all carboned up. Mine was running very rough with some black smoke on start up. I changed the plugs and all is well. I think the carbon is from running too rich. I used Champions because they were free with a rebate. I will go with AC 44RT when I run out of Champions. Rich running would be consistent with a stuck choke. Unless you just replaced plug wires also, I would install a new set of Belden plug wires from NAPA also. In my case, I only run my 454 in town on short trips, so that contributes to carbon build up. I usually replace my plugs every year, and that is only 2-3,000 miles or so. I am going to try some BG 44K and see if that helps.