timing

what is the best way to set the timing on my farmall h after i reassemble. thanks

I set it at TDC, then time it by ear.

I find it is easiest to get the final adjustment correct with two people. After the magneto is refitted and the timing approximately correct I like to have a friend turn the motor over on the crank handle and watch the timing marks. I stand beside the magneto (conveniently situated on the side of the tractor with no timing marks). You can hear the impulse coupling trip. This should happen at top dead centre, i.e. when the "first notch on the fan drive pulley is in line with the pointer". If the timing is not correct we keep moving the magneto until it trips at the correct point. You need to turn the motor over each time to re-check the timing. I have found the best results are obtained this way, because it eliminates any error, which could result from worn timing gears etc. You should be sure to disconnect at least the central high tension wire from the distributor cap so that the tractor cannot start and cause fright or injury. Always remember what IHC printed in their manuals: "The complete observance of [u:c544dc13de]one simple rule[/u:c544dc13de] would prevent many thousand serious injuries each year. That rule is: [u:c544dc13de]"Never attempt to clean, oil, or adjust a machine while it is in motion or in danger of being put in motion."[/u:c544dc13de] Good luck.
SadFarmall

I set at TDC and then get it running.

Advance distributor till it runs rough, take note of that position, turn opposite direction till it runs rough, take note of that position, go back to the middle of those two positions and tighten the set screws up.

I used a lead pencil to mark places on distributor. I do this at idle and again at WOT.

It's not too scientific but it is the way I was taught back in the day.

You may have to tweak it depending on how it runs under a heavy load. Having said that I have rarely had to redo it.

Yes, that will work OK, but I don't like my fingers near the magneto and fan when the engine is running. Of course, it is possible just to follow the instructions in the Owner's Manual.
SadFarmall

Do as Dean and David say, except rotate the distributer both ways until you get the highest rpm. I do it only at idle. It may need to be changed occasionally. Once you are familiar with the sound, you can tell if it is laboring or not.

THE best way is with a timing light and set for full advance at WOT. To factory spec's . Makes a world of difference . Oh and knowing what advance curve also helps.