the lazy farmer: How to remove the gearbox on a New Holland 358 Mixer-Grinder

My New Holland 358 Mixer-Grinder failed.

This is an embarrassing post. It is entirely my fault.

I didn't change the oil!!!

I bought this mixer-grinder ten years ago. I had been making feed for a couple people and the deal was that I was to borrow a New Holland 357 in exchange for making the people feed. When I took my groundskeeping life detour my neighbor reclaimed the mixer-grinder and bought his own no-till drill and the other neighbor hired someone else to chop his silage.

This could have been a clue... I was out of the club...

But, I digress...

Mixer-Grinders are impossible to find. I found this one on Craigslist and it was like three hours away. It had a hay feeder and the fellow swore it was ready to run. In fact, he agreed to deliver it for the moderately high price he was asking.

I had forgotten about this detail, but one of the selling points was that he had filled the main gearbox with corn header grease and it would never need to be serviced again. (corn header grease is solid at room temp but quickly melts when used in a gear box)

Now here is where I went wrong.

It is really hard to crawl under the New Holland 358 mixer-grinder. But, I have a forklift. I needed to get the gearbox warm and drain the grease. In fact, I really thought I did. I can remember working on it when it was 100 degrees and draining crap out of the gear box and refilling it with 90 weight. I don't know.

BUT....

What I never knew is that the seal between the gearbox and the mixing auger was out. This allows fines to work into the gearbox and mix with the grease. The grease will never completely drain through the small drain hole and so it forms a goup.

I did succeed in getting 90 wt into the gearbox because when it failed there was a puddle of 90 wt underneath.

What I did to make it fail.

The hydraulic conveyer I use to meter material into my mixer grinder quit. The belt broke. So I used the unloading auger on the Mixer-Grinder to fill the mill. I just idled the tractor down and let it run slow. I NEVER do this.. I always make a batch and then dump it into bags or the loader hopper and then shut of mixer. If you run the mixer too much at too high a speed all the fines settle to the bottom. You also wear hard to change bearings.

Yesterday I dropped the gearbox out.

It was surprisingly easy. (With a forklift)

First I blocked up the mixing auger. Then I removed the unloading auger drive chain from the main shaft and pounded the main drive to gearbox coupler back on the splined drive shaft. I used lots of penetrating oil and steel wedges to get the shaft moving.

Next I blocked up the gearbox and removed the four nuts holding it on. I rotated the gear box clockwise (I think) 1/4 turn and got out of the way.

When I pulled the cover off the gearbox it was solid burnt grease and fines. I cleaned it with a pocket knife and a big screw driver.

The gears are pretty bad. All the bearings and seals are bad. Probably need at least one new shaft. Plus, I have to figure out how to build a new seal. CoPilot says they can find me a more modern seal if I give them the shaft size. I think I will just cut one out of a truck mudflap...

I will drop some photos and then I have to go to work. My Nephew says I have to help deliver a load of hay today. I think he is trying to kill me so he can live in my trailer house and have my Studebaker car...

Bottom line is this: If you buy a 30 year old mixer grinder for cryin out loud, CHECK THE GEARBOX! Better yet, just remove it and clean it out. It wasn't that hard to do...

I uploaded my pictures in reverse order...