I found this older discussion and it seems very similar or same to my problem: http://www.yesterdaystractors.com/cgi-bin/viewit.cgi?bd=ac&th=83007
I have a 47 and a 49 C. The first one smoked badly so I pulled the head and had it redone. New valves, guides, rockers polished, etc. Now it runs smoothly at idle or when not under a load, but add power and it sputters and backfires. I decided to sell it as I could not fix it. So, I did the head on the good C just to make sure it was OK (since the other one had broken rocker shaft etc). Now that tractor does the exact same thing. No power, coughs and backfires when pulling, no power.
No matter what is wrong, what bothers me is what I did that caused the exact problem on both tractors? And how did these other people have the same problem when they changed the head? What could we have done? What on earth is the problem?
(I tried gas, plugs, wires,...nothing helps)
I have a 47 and a 49 C. The first one smoked badly so I pulled the head and had it redone. New valves, guides, rockers polished, etc. Now it runs smoothly at idle or when not under a load, but add power and it sputters and backfires. I decided to sell it as I could not fix it. So, I did the head on the good C just to make sure it was OK (since the other one had broken rocker shaft etc). Now that tractor does the exact same thing. No power, coughs and backfires when pulling, no power.
No matter what is wrong, what bothers me is what I did that caused the exact problem on both tractors? And how did these other people have the same problem when they changed the head? What could we have done? What on earth is the problem?
(I tried gas, plugs, wires,...nothing helps)