1655 Gas

Recently rebuilt engine in 1655 gas. While in the field the muffler turned red and glowed. When the engine was shut down it
dieseled for a bit and then stopped. The oil level was ok and the coolant temp never rose. Any thoughts.

Running rich? Did you do anything to the carb? I remember I tried to do a timing adjustment on my 302 with out a timing light and had my old Montego back firing and dieseling when I stopped. A real mechanic told me I was way advanced on my timing. He was surprised car even ran.

Also, running it lean will make it run hot too.

(reply to post at 17:52:36 07/13/20)

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I can think of a few possibilities;

The cam timing may be wrong which would effect the both intake and exhaust sides letting the exhaust valve open too soon thereby letting still burning gasses out into the exhaust, or some (or most) of the exhaust valves may be too loose and not closing completely. But the tractor would run -less than perfectly- throughout the RPM range I believe.

Two is simpler - the timing is retarded too much, also allowing the still burning gasses out into the exhaust. If the timing sparks the plug too late the engine will labor some and the gasses will not be finished combusting when the exhaust valves open. Burning gas inside a muffler? It's gonna get hot in there.

The third was mentioned already by alberta dave, running much too rich.

J.Wondergem's suggestion works just the opposite, the gas combusts too quickly along with not enough intake cooling from the fresh mixture coming into the cylinder. That overheats the engine itself, not the exhaust system. A lean condition almost always shows itself inside the intake tract I believe. It has on my engines anyway (not tractor engines). My Harley is a case in point, it's old, been modified for the drag strip, and the carb is flightly. Rejetting and timing are critical. Lean spits back out the carb, rich barks out the exhaust, lean overheats the engine, rich doesn't overheat the engine but the engines not making peak power. Valve/cam timing is usually evident as soon as the engine is started. Loose valve(s) should be heard easily enough. Use a stethoscope or long (plastic handled) screwdriver to listen to the inside of the engine near each valve group...can't hurt. Even slight ticks can be heard.


Any of these conditions will wear on the exhaust valves pretty quick and so should be fixed asap. If your muffler is glowing think of how the exhaust valves must be looking.

YMMV

The muffler was glowing because it was homemade out of some very thin sheet metal. The engine stopped when the oil pump gear lost a tooth .

(reply to post at 17:52:36 07/13/20)

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One more thought on the dieseling...in the past my experience has been that that is caused by the throttle plate not closing completely. Obviously with it cracked open it will still be getting enough mixture to continue running. That is brought on by really hot exhaust valves igniting the gas mixture as it enters the combustion chamber. In essence, there is a glow plug effect going on. The last I heard gasoline doesn't react to compression by exploding the same as diesel. But things change.

Thee early 1800 tractors would do that. One thing we did was unhook the air intake at the carburetor and then we would take a squirt oil can filled with water and feed it to the engine which soften the carbon deposits on top of the pistons and would solve the problem for a while.