The orange HS40 tecumseh with the 1" PTO shaft needs to be turned down to 3/4". In order to do this, the crankshaft needs to be removed. And while we're at it, we'll remove the tecumseh governor. All the internal parts that is, per the suggestions by others above.
Since the block is already stripped of parts, including removing the flywheel, this is pretty straightforward stuff.
1. drain the oil! I guess if you're just removing the governor, you could skip this step (and just have the motor angled so the oil is towards the flywheel side case.) But since we're removing the crank too, the oil needs to come out.
2. If you have a 1" PTO, it's not a bad idea to clean up the entire length of the PTO. The side cover will come off easier. I used some 100 grit sandpaper to get the rust and crap off my 1" pto shaft.
3. with the engine angled towards the flywheel at about 45 degrees, remove the eight 3/8" size bolts that hold the PTO side cover. The angle will keep what oil is in the block towards the flywheel side, instead of dripping on you!
4. I use a rubber mallet and hit the sides of the block cover near the oil input holes, to break the seal and split the case. Usually that knocks the cover loose enough so you can wiggle the cover off, and slide it off. Like i said, if you have a 1" PTO, the side case cover will come off harder, than say a 5/8" or 3/4" PTO engine.
5. With the side cover off, you can see the plastic governor gears on the side cover. Mentioned above, the plastic gears can get hot and melt, especially if you're like me and sub'ed the governor spring with a straight wire. There are two small C clips holding the plastic governor assembly to the side case. Remove the clips and remove all the governor parts.
Below is a picture of the removed governor parts.
6. The metal shaft (which held the plastic governor gears) can stay in the side case. My guess is some people will cut it clean to the side of the case. But i don't really see the need for that. Likewise, the "L" bracket on the right wall of the block (which connects to the exterior governor arm) can also stay. These things are just "hanging in the wind" now, and don't touch anything. I guess if you want to go to a more simplified throttle system, you could remove the "L" bracket, and plug the block hole. But i don't really see a need for that personally. I'm sure others may have a reason for removing these two items though (feel free to chime in.)
The purpose the L bracket was to ride on the governor gears (which are now removed). So again, you can remove it, but they you'll have to modify your throttle system and plug the block hole. Not that this is a terrible thing to do, but i'm not sure there's really a big upside to it.
In the above picture you can see the connecting rod is unbolted, the cam and lifters removed, and the crankshaft removed. That's because we are now ready to put the crankshaft in a lathe, and turn the PTO side down from 1" to 3/4", and re-cut the key way.
Since the block is already stripped of parts, including removing the flywheel, this is pretty straightforward stuff.
1. drain the oil! I guess if you're just removing the governor, you could skip this step (and just have the motor angled so the oil is towards the flywheel side case.) But since we're removing the crank too, the oil needs to come out.
2. If you have a 1" PTO, it's not a bad idea to clean up the entire length of the PTO. The side cover will come off easier. I used some 100 grit sandpaper to get the rust and crap off my 1" pto shaft.
3. with the engine angled towards the flywheel at about 45 degrees, remove the eight 3/8" size bolts that hold the PTO side cover. The angle will keep what oil is in the block towards the flywheel side, instead of dripping on you!
4. I use a rubber mallet and hit the sides of the block cover near the oil input holes, to break the seal and split the case. Usually that knocks the cover loose enough so you can wiggle the cover off, and slide it off. Like i said, if you have a 1" PTO, the side case cover will come off harder, than say a 5/8" or 3/4" PTO engine.
5. With the side cover off, you can see the plastic governor gears on the side cover. Mentioned above, the plastic gears can get hot and melt, especially if you're like me and sub'ed the governor spring with a straight wire. There are two small C clips holding the plastic governor assembly to the side case. Remove the clips and remove all the governor parts.
Below is a picture of the removed governor parts.
6. The metal shaft (which held the plastic governor gears) can stay in the side case. My guess is some people will cut it clean to the side of the case. But i don't really see the need for that. Likewise, the "L" bracket on the right wall of the block (which connects to the exterior governor arm) can also stay. These things are just "hanging in the wind" now, and don't touch anything. I guess if you want to go to a more simplified throttle system, you could remove the "L" bracket, and plug the block hole. But i don't really see a need for that personally. I'm sure others may have a reason for removing these two items though (feel free to chime in.)
The purpose the L bracket was to ride on the governor gears (which are now removed). So again, you can remove it, but they you'll have to modify your throttle system and plug the block hole. Not that this is a terrible thing to do, but i'm not sure there's really a big upside to it.
In the above picture you can see the connecting rod is unbolted, the cam and lifters removed, and the crankshaft removed. That's because we are now ready to put the crankshaft in a lathe, and turn the PTO side down from 1" to 3/4", and re-cut the key way.
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