Yes to a tear down and rebuild of the pinion. The 4 bolts that hold the what-cha-dingy to the pinion gear were gone. found one of them in the bottom of the case. Your right, I do not want to do this again because I did not pay attention to something. Never be any closer or easier to repair. Will evaluate clutch disc also. Seems to have only about 1/16 inch proud above tooth center. Not sure what new is.
thanks
marc

Pembroke, NH

I just rebuilt the start pinion clutch assembly on my D4 7U, working on getting a video up - helpful tip is soak it in vinear for a few days. For me, worked really well and much cheaper than evaporust

I have cleaned parts before using vinegar. It is better when a person can get their hands on something stronger than 5 "grain" vinegar, which was the norm for household use.
Vinegar strength is measured in "grains", just as your favorite hootch is in "proof". If you're feet ache from standing all day wrenching on your iron, soaking your feet in hot water with apple cider vinegar is not only soothing, but good for you. Nice and tingly too.
Cleaning parts without the chemical smells or worrying about hazards using ACV is great too.
I should see about buying a drum of the "good" stuff from somewhere. JM

Good Friday morning all. This topic interests me because I own a D 2 4U5401X 1952 model. Grinds reall bad on start up and I need to fix that. I just don’t know where to begin, Split the tractor? Remove the pony? I know it’s necessary to gain access to the pony clutch. I flushed it with kerosene and didn’t help. I’m new here so please allow me to serve y’all. I will not lead anybody wrong. This machine is new to me. Thanks a million

mike that should really be its own topic but ill be brief.
the pinion clutch mechanism also has a clutch brake.
to apply it you hold the clutch lever in the disengaged position as far as it will go this stops the pinion turning so you can engage it smoothly with out damage. try that first.

if the mech is worn and not kept adjusted and rebuilt with new wear part as needed it doest work and it damages the fly wheel and pinion gears.
get a copy of the serviceman reference for your machine. the owners maintenance instruction and parts book/s are also useful(each attachment has it own book)
yes the pilot engine has to be lifted so you can get the pinion shaft out to repair it. get a boroscope and remove the inspection cover for the clutch/flywheel housing and inspect the ring rear for damage before removing the pinion set up. this will help show how big the job needs to be.

Mix some water softener pellets with the vinegar, soak your parts in it and give it a few days and it really works.
Make sure to neutralize it when you wash it off.

Be careful of vinegar stronger than 5%. I just attended a class on herbicides and of the many discussed, 20% vinegar was the most dangerous for the user. Full hazmat suits and eye protection were required. I have used the 5% many times and was surprised that the stronger stuff was so dangerous.

The 20% and up concentrations are very caustic and particularly damaging to the eyes. Wasn't aware of the hazmat suit requirement but one sure has to avoid skin and contact with the eyes minimum of goggles, rubber gloves, and long sleeved clothing. The 20% will start to burn the skin after a few minutes of contact. (from experience) I never really read about it's toxicity but figured to treat it similar to CLR.

Hey Grant. Sounds like a great suggestion but how do you neutralize it. I’m thinking maybe pour coke cola on it But I’ll bet you just flush it with water. I’m thinking of cleaning pony motor clutches with it. Thank you