timing help on a SC

I purchased a SC that was not running and the magneto had been stripped off and one replaced by someone who did not understand how the magneto worked. I have had problems getting it to run. In checking out the timing of the magneto, the book says when the dot is visible on the flywheel I should be at #1 top dead center and the magneto coupling slot should be up on the right side 25 degrees. In checking it out, when the dot is visible the slot is located down on the right side not up (hope that makes sense). I do not know if someone pulled out the magneto drive shaft and did not put it back in the right place. Is this a case of pulling out the shaft and rotating it a tooth on the cam shaft gear? Since this shaft controls the magneto timing and the governor, do I run into problems by pulling it out. I hate to pull it and have parts go everywhere!! How big a mess am I in and how do I correct the problem.

thanks for any and all help

Bill

Actually, I think the engine is supposed to fire when the piston is 1/2 inch before TDC?

Do not worry about what angle the slot is at. If the magneto trips at the right time that is all that counts. Some guys get all bent out of shape when #1 wire is at a different position on the mag cap than the manuals show it. Get the dot in the hole on the compression stroke TDC #1 piston. Install the mag so the rotor is pointing at the #1 wire. Turn the engine over twice to TDC #1 again, and fine tune the mag so the impulse trips right as the dot is in the hole. Should run.

Trouble is the magneto fires with the slots up on the right side. As it is now it is firing about half way down the stroke for top deep center, I cannot rotate the magneto enough to bolt it up and fire and top deep center, unless I modify one or the other unless I am missing something.

(quoted from post at 02:57:16 04/12/16) Trouble is the magneto fires with the slots up on the right side. As it is now it is firing about half way down the stroke for top deep center, I cannot rotate the magneto enough to bolt it up and fire and top deep center, unless I modify one or the other unless I am missing something.

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First let me say I am no expert I have gotten lots of help from all the good folks here. What I do have is an SC that I already took apart so if you need pics of something just ask. Mind you I'm not telling you this is what you HAVE to do.

As far as how much trouble to remove the cover and check that the gears are aligned A lot. Well let me say first there's 2 dots on the camshaft gear and one dot on the governor gear that should line up. To get the cover off you have to get the crankshaft pulley off BUT because the handcrank start shaft and support is in the way of getting a puller on the crankshaft pulley there's a lot more work. In order to remove the pulley you have to pull the rad hoses gen or alt belts wires along with the entire front wheel portion of the tractor Remove the 6 main bolts, block up the front end and the front of the engine then slide the rear of the tractor back. The pulley is held on by a soft tapered steel pin look in the hole on both sides and drive it from the side with the smaller diameter. Easy to get out with a rivet gun and a 1/4 pin punch (Rivet punch). Beating on it with a hammer and punch is not a good idea you can damage the forward crankshaft bearing and your not likely to get it out don't ask me how I know. Now once the pin is out you will need a puller to remove the pulley some are easy some are not mine came off easy. Once that is off pull the bolts holding the cover there's nothing that is going to pop out were your governor is. There is only a small spring I think its 3/8 diameter that's fit inside a hole in the camshaft. This holds the camshaft back in place it is not likely to come out when you pull the cover.

Now let me address what will happen if you were to pull the governor out. There is nothing in there that's going to pop out if you remove it the gear spline is slightly skewed in one direction so it would likely rotate a little as your removing it. However there's no way to see that the marks on the cam and the governor are aligned.

I hope this helps somehow?
Best of luck Byron

If you pull the gov. housing mark the shaft and housing so you can put it back to the original position if needed, make sure you are on tdc compression and not exhaust and check to see if the governor finger has a flat spot worn on it, that makes a lazy governor and needs to either be replaced or built up so it is curved where it runs against the bearing, another way to cure your problem is to replace the mag with a distributor which can usually be bought for $100 or less with readily available and reasonably priced coils and other parts being a big advantage

As a followup, pulling the magneto drive shaft was not a problem and I was able to rotate the gear meshing by two teeth, all lined up as it should. Great news doing that resulted in the tractor running. thanks to all for the help.

Bill

Did you look at the governor finger?