IHC Super M Farmall help, Please.

Hello, My brother inherited a Super M farmall from a friend's widow and we would desperately like to have it running right for our local show to honor him. PROBLEM: Starts and revs up fine. Runs fine while under load (like pulling a hill). When you reach level ground or start downhill, it misses. He says he can't bush-hog the widow's ground because under that load it just misses too bad. I rebuilt the carb for him and found some fine rust by the main metering valve, cleaned it and opened all six orifices. He says it's slightly better, but not right. Could someone PLEASE offer some experienced insight?? I'm thinking about the governor next. Any way to test the spring besides replacing and trying it? I haven't seen in there yet. These tractors are not my area of expertise. Any advise?? Thank you very much in advance, Luke.

Sounds like a mag problem.Does it get worse when the engine warms up?The insulation on the coil in the mag breaks down over time and may short out when it gets hot.Rob

Rob is totally correct. Carb and ignition symptoms are identical. Whether or not it has mag or electric ignition, try new plugs! On the other hand, I had a John Deere D that would run fine all the time EXCEPT when I made a left-hand turn. Then the engine would want to die. Get going straight and the problem went away. Almost went NUTS on that one but I finally took ALL the fuel lines off and discovered a capsule-like mass of bugs that was floating about in the fuel line. On a left hand turn it would plug the supply! Same thing in my JD L. Found a piece in the gas tank that would find its way to the gas tank outlet and stop the engine. Don't overlook physical troubles. Craig

check the float for saturation. also double ckeck the float hight.

Hello! Thank you for your responses!! FYI- This tractor is coil ignition (not mag). It was switched from 6 volt to 12 volt many years ago by my friend, the former owner. It's always nice to hear input from others in situations like this. Please keep them coming! I'm going to be at my brother's this Saturday to work on the tractor. Thanks again!! Luke

You might want to check for an intake manifold leak.

The best way I've found is to remove the carb and, while holding the palm of your hand over the carb flange on the manifold, crank the engine or get someone to do it for you.

You don't have to crank fast. Listen for the telltale hiss of a leak or feel if the suction against your hand fades fast.

You can also squirt oil on the outside of the gaskets when the engine is running to see if there is a change or if the exhaust gets smoky (smokier).

Take care - Elden




Elden's Junky Web Page

check the polairty on the coil or swith the wires if it was switched frome 6 to 12 volts if it has an alternator it was probly changed from positive to negative ground and the coil mite not have been changed just a guess. don baker

[CharlieBiler]

My two cents,
First, Make sure the distributor side of the coil is the same as the ground on the tractor. I.E. negative ground tractor equals negative side of the distributor.
Second, check the points and condenser. The condenser should be 0.015-0.020mfd. If not, replace. The points are set at 0.020" after filing. Wipe them with a CLEAN COTTON cloth after gapping. The plugs should be light grey and all the same. If not, replace them.
Next, after that warm the tractor up and run it at a medium idle. At the carb throttle, snap it open. It should immediately come alive with no spits or sputters. If you already set the float and cleaned the carb, open the high speed one quarter turn and repeat until it snaps to life. This is the minimum setting for performance. Three quarters of a turn more will give you ten percent more power with twenty five percent more fuel consumption.
After this, I go for the exotic stuff. Corn Binders in the M flavor are not going to run if they have jumped time. Keep fingers off the governor.I said so.They ain't rice burners. Their intake gasket is normally okay if the bolts are still tight. A bad intake will show up as hard starting and one plug will be leaner than the rest, or glazed. If the engine runs at full load with the carb bowl drain cracked open one turn, the tank and filter are okay. If not, clean the filter and tank. It should run out as if it were taking a leak, with no slowdown. Let me know the final result.
Happy motoring.

[Ken Majeski]

Well.... I have seen a couple H's M's ect that run Terible with No Load but will pull Fine. What I have found is that the Valves and Seats have been ground Many times and the valve springs have not got any stronger over the years And with the seats ground Way down in the head the springs will be too weak especially on the exhaust valves. It would be a simple matter to pull the valve cover and see how easy the valves push down. Weak exhaust valve springs will make a TG Gas Engine run Bad and a tractor is No Exception..

[CharlieBiler]

Originally Posted by Ken Majeski

Well.... I have seen a couple H's M's ect that run Terible with No Load but will pull Fine. What I have found is that the Valves and Seats have been ground Many times and the valve springs have not got any stronger over the years And with the seats ground Way down in the head the springs will be too weak especially on the exhaust valves. It would be a simple matter to pull the valve cover and see how easy the valves push down. Weak exhaust valve springs will make a TG Gas Engine run Bad and a tractor is No Exception..

A very keen observation and one I would never think of. To me, the opposite would be intuitive. Guess that is why intuition watches while experience gets it done.
I have the habit of tossing valve springs when I do a valve job. I never really check many of them, unless they are really oddballs. I am the guy that supplies all the Moline valve springs. I add an extra wrap on the coils to reduce fatigue. I also insist that the spring pressure be at the top of the spec and not at the middle. A five percent increase in horsepower can be gained by new valve springs. I also toss valves that do not have at least half of the margin remaining, after refacing.
As for your web page; major bummer for me. Why don't you live next door so I can help you with those toys. I can only see one downside. If the wife unit wants you gone, she yells," whoever kills him, gets his junk".