Starter Removal

Can anyone explain how the Bendix gear engages with the flywheel? Tried to start the 9N and heard that terrible "clunk". I recognized the sound from hearing it many years ago, and dreaded the chore of having to work the Bendix gear from around the flywheel. This time, however, the rear plate of the starter motor will not separate from the tractor, and it feels like a spring action is keeping it attached.

Please help!

The bendix moves forward to the flywheel to engage. Low voltage will cause it to engage, but not turn the flywheel.

Charge the battery, clean the cables/grounds and try again.

Or put it in gear and turn a rear wheel.

But if you need to pull the starter..........

The starter has 3 major exterior components; front plate, barrel & rear plate. The 2 bolts that hold the starter on to the bell housing go through all three components & hold it all together. To remove the starter, unscrew the bolts out of the block & put a nut on one of them. Otherwise, the starter comes apart. Not fatal, but not fun either. (tip # 36 at the link below) Then, loosen the two bolts holding the oil filter canister to the block, (it does not need to be removed) remove the dipstick, and keep the starter close to the block while pushing the front of it down and lifting the back up. Sometimes you have to remove the drain petcock as well. The bendix is behind the flywheel; your job is to get it over the flywheel.

Caution: while the starter is off, resist the temptation to screw with the bendix. If you extend the bendix, and it is not the OEM bendix w/ the big spring, you will have a hard time getting the starter installed.

To install the starter, keep it close to the block while pulling the front of it up and pushing the bendix back into the hole. The bendix has to go behind the flywheel; your job is to get it over the flywheel.

Lastly, while the starter is off, polish the block & all starter mating surfaces w/ sandpaper to insure a good electrical ground. First, clean the mating area between the barrel and rear plate. Then, clean the mating surfaces where the aluminum rear plate meets the bell housing. The starter's ground circuit is not only through the two long bolts but from the barrel to the rear plate & then to the bell housing as well.
75 Tips

Thanks, Bruce, for the tip about the forward movement of the Bendix. Now I can visualize what is happening inside there.

The battery is new and reads 16 volts. The last time I tried to start it the starter tried to turn, but couldn't, and some smoke came out. I'm guessing the Bendix is not releasing. I tried pulling the tractor backward a couple of feet with transmission in 3rd gear (from an old post by Zane Sherman) (God, I miss him), but it didn't work. I will try your suggestion and jack up a wheel and turn while in a forward gear. If that doesn't do it I may pull it along the driveway. Thanks, again.

A fully charged 12v battery should read 12.65 volts. When you take it off the charger, it will read higher, like 13v or so with a 'surface' charge that should dissipate as soon as you hit the starter or w/in 24 hours. At 16 volts, you have a defective meter or a seriously over charged battery.

You can also put the tractor in gear, engage the pto, and turn the pto shaft w/ a pipe wrench.

Are you able to remove the case of the starter from the bell housing?
75 Tips

This would be a good time to get a crank handle. I have one that came from my '48 Dodge truck that I drove for years,using the crank handle more than one time. If you can get it to start,the starter drive should retract. This site has the crank handle,or used to.

Thanks again.

Let me fill in some gaps. I did a 12-volt/electronic ignition change about a week ago, hence the new Interstate battery. I checked the battery voltage before installing it, and it read 16 volts. After the conversion the tractor has been started five or six times, and has total running time of about an hour, with battery still at 16 volts. Everything seemed fine.

Then came the "clunk" sound with the starter motor freezing up. I tried removing the motor, but the rear plate on the housing will not come free. I tried driving a chisel between the rear plate and engine block but the plate would move only about 1/16 inch, and would go back when the chisel was removed. I tried removing the front plate and the cylinder casing, but there is not room to remove it with armature remaining there, connected to the Bendix. I reassembled the motor casing, tried starting, but the motor will not turn, though it tries. This morning I removed the spark plugs to eliminate compression, jacked up one rear wheel and turned it forward in 3rd gear. The engine would not turn, although the opposite rear wheel turned in reverse and nearly moved the tractor off the jack stands. I had planned to pull the tractor with another vehicle, but I am afraid I might cause further damage.

I think I may have to split the tractor to expose the flywheel and Bendix, and perhaps disassemble the motor from that side. The FO-4 manual shows an exploded diagram with a pin through the shaft, and a retaining ring, one of which may allow the Bendix to come apart. Seems like a lot of trouble for what should be a simple fix.

I still welcome advice.

" I had planned to pull the tractor with another vehicle, "

Do it.

Put the tractor in 4th gear.

Slowly release the clutch.

And find out why a 12v battery is reading 16v before you blow it up.
75 Tips

If I were you, the first thing I would do is test the battery with a different VOM. Something sounds haywire with yours.