More about rebuilding the gearbox on New Holland 358 mixer-grinder

For some strange reason I did not publish my post about rebuilding the gearbox on my New Holland 358. It was pretty straight forward rebuild as I did have a New Holland Service manual.

There were two difficult parts. Assembling and setting the preload on the input shaft bearings was a pain. Hint- don't bend the cotter pin over the end of the shaft... Removing the drive block was a bugger.

To set up the input shaft bearings you have to install the bearing race on the input end of the shaft first. Make sure you put the cup in the correct way because you are going to next install the race, then a spacer, then the second race, then the second cup. You line this all up perfectly and set the preload like you do a wheel bearing, but don't install the cotter pin. Because then it all slides into the gearbox and you have to remove the nut and install the bevel gear, recheck the preload but don't bend the cotter pin over the end of the shaft because when you adjust the backlash on the big pinion gear, the cotter pin will hit the gear or the funny little oil splasher thing that I have no idea if I installed correctly. The gear clearance is set by sliding that bearing/spacer assembly in the gear case and then locked in with a set screw. Seems a bit on the hokey side but what do I know? It was so far out of adjustment when I took it apart I suspect it is a problem area.

The input shaft pinion clearance is set by knocking the bearing assembly into the case until you have correct backlash between small and big pinion. Then you tighten the set screw on top. This may or may not work...

The drive block was rust welded to the output shaft. I heated it red hot and let it cool about five times. I applied ATF and acetone, finally I used some 100 year old Kroil  that I got from MuddyValley and let that soak over night. Next morning it had penetrated the splines. I put it in the press and the shaft popped out.

If you look closely you can see a faint red glow. It took a few heat cycles and every type of penetrating oil on the farm to break it loose. Also, a big press. Kroil actually soaked all the way down the splines.

I thought the seal kit meant it came with a seal. It is just a $150 shield. I used it instead of returning it as the enter hole was actually smaller on the new part. Plus it was shiny.

You can see the shield in place. It protect the seal on the output shaft.

It held up for 1800lbs of oat/alfalfa pellets of which most are sold so I consider this repair a success