c123 governor

My farmall 100 had a lot of slack in the housing bushing for the thottle rod lever. So I pulled the housing and with out thinking I pulled the drive gear out of the engine. Now I need some one to tell me how I need to go about putting it back in time.

If you did not mark it before you pulled it out then it would be next to impossibal to set it up right with out removing the front timing cover.There is a single punch mark on the camshaft which aligns with a single punch mark on the crankshaft, these would be uneffected. The double punch mark on the camshaft should align with the double punch mark on your governer gear. You may try sticking a flexibal mirror through the governer housing hole and rotating the engine until you know where these marks are and then reinstalling the governer drive gear. If that does not work than you will need to remove the front timing cover. I have pulled several of these engines apart for rebuild and found these marks not aligned and the governer did seem to function fine. But to do it properly punch marks should line up with each other.

There's a way to do it without pulling the front cover. It involves some variables, like whether you have a battery ignition or a magneto and whether the motor or the ignition have been moved.

Keep in mind that the marks Jonathan described on the cam and governor gears are to be in register with the motor at TDC on the compression stroke, so when the motor is in that position, the mark on the cam gear, even if you can't see it, will be at the point where it should mesh with the governor gear.

IF neither the motor or the ignition has been disturbed, you should be able to put the gear directly back in, with the slot and the lug between the gear and the ignition drive lined up. It would be preferable for the alignment marks between the two gears to line up, but if everything else is in place, there's no harm in that gear being exactly 180* out. It would be advisable to re-time the ignition afterward in case you are off by a tooth, especially with a mag, but it should be close enough to run. One further caution, though, with a mag. Use your electric starer, NOT the hand crank, to start it afterwards and until you have loosened up the mag for the final adjustment -- if you should be off on the advance side, that crank can kick you.

Just to verify that it worked, with the gear in place and the ignition off, you can then turn the engine by hand (much easier with all four plugs removed) until you have #1 at TDC on compression. At that point, if nothing was moved while it was part, the marks on the governor gear should either be meshing with the cam gear or 180* across. If the mark should be on the opposite side, then pull the gear back out and try the mirror as Jonathan suggested to see if you can see the mark on the cam gear, which should be just at the point where it meshes with the governor gear, and can then line up the gears according to the marks. It couldn't hurt to make a mark on the body of your mag or distributor even with the tower for your #1 plug wire, then pop your distributor cap to verify that the rotor is pointing toward #1. If it is, the most you will have to do is the routine timing adjustment, just in case you are off by a tooth on the gears.

If it is not pointing to #1 when the motor is at TDC, then one of two things happened. If it is pointing to #4, there's a good chance you had #1 at TDC on exhaust instead of compression. With the governor gear in place turn the motor by hand to verify that you are indeed on compression on #1. If the rotor is still not pointing to #1, pull the governor gear back out and turn the ignition until the rotor is pointing to the mark you made for the #1 wire. (You may have to remove the mag to do this, but a battery distributor should turn easily in place.) Then replace the gear with the marked tooth meshed as closely to the cam gear as it can be.

Again, at this point, all you should need is to make the regular minor adjustment to your timing by either turning the mag on it's mount or the distributor.

Let us know how you make out.

RDJ: Not near as complicated as you think. Turn engine to TDC on compression number one plug, then slide the gear back in with rotor pointing at 2PM standing behind it. You may have to remove distributor, however that is not complicated. Main thing here is rotor at 2PM when Number 1 is at TDC compression. Not hard to find compression, stick finger in no. 1 plug hole and turn hand crank.

Those guys are making it more complicated than it is. Do as Hugh says and get it at TDC and clean the gear well you should find the marks to put it together right. You will know if it is right by rocking it back and forth with the fan with the dist cap off the points should be just opening and closing as you rock it.

Thanks for the help. Now I just need to try to get it together. Next time I need to ask questions before I start.(My wife tells me I need to learn to pay attention. I hate it when she's right.)

Go for it. That's actually a nice little project.

I get a little long-winded sometimes (well a lot of the time actually), and teddy is pretty succinct, but we've all got the same idea. Put the gear in anyway that it will fit up against the ignition drive and pull the motor around to TDC on #1 compression and see how things line up and go from there.

Best of luck, and keep us posted.

(If supper's over, there's still time to sneak out tonight and give it a try!)