K301 Backfires and more

[Rivets]

I still think you should look at that straight pipe. If you are not providing back pressure on the exhaust valve, it may be floating, which will allow raw fuel to enter the exhaust port. This will be indicated by flames out the pipe. Most people don't realize that both valves are open at the same time between the exhaust and intake strokes. Even with the fuel and timing set correctly, you will still experience backfiring. Those of us who were modifying our car exhaust systems in the 60's with straight pipes will remember that we get alot of barking and police stops until we started changing the valve timing also. Lucky I lived in a small town and knew the officers, but I did get my share of verbal warnings on a 383 with 4 barrel Holly and Hurst 4 speed. Slowing down sounded like jack braking.

 

[Polaraco]

I've also ran into the same problems when someone has replaced the Kohler ignition coil with a cheap automotive style coil?

I can't see how that would make a difference. You have any idea why?

I see the combustion continuing outside the cylinder. But good running car engines with no manifolds will do the same thing. Rivits might be right. I didn't think about these little engines needing some back pressure.

That's a MPG trick the auto manufacturers do to increase economy. The more back pressure, the longer the gases burn in the cylinder. Open pipes is a trade off for more power.

 

[cashman]

I really don't know why that some of those coils wouldn't allow the engine to run right. Especially at idle speed. I've always figured it was the way the coil was wound inside or mismatched voltage or another problem somewhere else? I don't know. When you tried everything else,you could change out the coil with the one from Kohler and it would straighten out.

 

[Wheel Horse Guy]

Bertsmoble1 and Polaraco, one carb is new and runs great on my other tractor. Only one adjusting screw, but I will try it again.

Cashman, I will set the timing with the light.

Thanks all, I will have to wait for a warm day to do this work.

Rivets, I will take the muffler off my other tractor and try it. I live in a small town too, never any verbal warnings,
only tickets for loud pipes, among other things, on my 383, 4 barrel, Hurst 4 speed 1968 Road Runner. That was
in 1973 and I was 17. Now I am 60 and I still have the Road Runner in my garage, sitting since 1979. All original
and waiting to be restored. Since then I only drove it once, in 1994, to the house we are in now and I was 17 again.
Figured I better wait until I was older to restore it or I would start getting tickets again. Still not sure its time.
What Mopar did/do you have?
Robert

 

[Rivets]

Did have. First a 1970 Blue Challenger then graduated to a 1969 Yellow SuperBee. Bought them out of the bone yard, rebuild and painted, raced at the local drag track grudge night, sold for a 100% profit. SuperBee paid for the fist year and a half of college. Today drive an SUV 6 cylinder, not as much getup and go, but gas milage is better.

 

[Polaraco]

Bertsmoble1 and Polaraco, one carb is new and runs great on my other tractor. Only one adjusting screw, but I will try it again.

Cashman, I will set the timing with the light.

Thanks all, I will have to wait for a warm day to do this work.

Rivets, I will take the muffler off my other tractor and try it. I live in a small town too, never any verbal warnings,
only tickets for loud pipes, among other things, on my 383, 4 barrel, Hurst 4 speed 1968 Road Runner. That was
in 1973 and I was 17. Now I am 60 and I still have the Road Runner in my garage, sitting since 1979. All original
and waiting to be restored. Since then I only drove it once, in 1994, to the house we are in now and I was 17 again.
Figured I better wait until I was older to restore it or I would start getting tickets again. Still not sure its time.
What Mopar did/do you have?
Robert

Did have. First a 1970 Blue Challenger then graduated to a 1969 Yellow SuperBee. Bought them out of the bone yard, rebuild and painted, raced at the local drag track grudge night, sold for a 100% profit. SuperBee paid for the fist year and a half of college. Today drive an SUV 6 cylinder, not as much getup and go, but gas milage is better.

Ahhhhh Mopar guys. Men of my own heart.

Rivits don't be ashamed of that. It's what things are today. I am restoring a 62 New Yorker just for those need for speed emergencies. LOL

Wheel horse. I was thinking. Does that have threaded pipe on it? I was thinking you could try a reducing coupler on the end and see if that makes the difference. Might quiet it down a bit too. Cheap way of finding out. Just a thought

 

[Wheel Horse Guy]

Polaraco, yes it has threads and I have it reduced from 1" down to 3/4" because that is what the muffler.
Thanks, all. HAPPY NEW YEAR!