New Holland TC21 needs a little repair

[Ken M]

For your entertainment.....

After looking for a small used front end loader that I could afford, I found a 1998 New Holland TC21 the end of 2013. It had about 1200 hours on it, 9 x 3 gear transmission, had not been well maintained and had never seen a barn or garage so it is a bit weathered but it was within my price range. (that's another story). I don't have indoor storage either so I used a tarp until just recently when I put up a hoop shelter that I could drive under. Much better but as the photo shows it's not exactly how I envisioned it being used.

About mid October I had it out while cleaning out some old hedge stumps. It was in 4wd and as I drove it out of a rough uneven spot I heard a loud crunching sound and the machine came to an abrupt stop. Not good. I managed to get it free and very slowly back to the garage. Definitely a problem in the front differential. I blocked the tractor up and started the tear down. It's never a good thing when you drain the oil and get chunks of metal coming out. I had to remove the entire axle. The cross shaft in the differential that holds the side gears had broken and elongated it's mounting holes in the housing. Amazingly enough all the gears were still ok. Actual parts needed were about $225 but all of the seals and o-rings had to be replaced and they are all non-standard sizes so I had to also purchase from the dealer. Two seals for the king pins were $43 each!! Total repair $452 plus $25 for a manual.

So after all this work I take the tractor out for a test drive. In 2wd all is good and running smooth. I engage the 4wd and have crunching in the rear transmission!! I was afraid of this....the 2 gears in the rear that engage the front drive are also missing some teeth. Whoa is me. Discouraged, I talked to a mechanic at the dealer to see what kind of a job this was going to be. Ball park estimate is 6 hours for tear down, 6 hours to put together plus whatever time needed in the tranny plus parts of course. Oh, and this is at $80 per hour. Not picking on the dealer mind you. So it comes down to this...If I fix it myself I can still probably sell machine for about what I have in it. And I guess I'm a DIY kind of guy anyway. So...purchased the manual.

Tractor is stripped down. Eight more bolts and tranny will come free of clutch housing so I can pull shafts out. I see 2 drive gears without teeth. About $95 for both. Two other gears with shift grinding damage ...may not replace. Probably some seals. What a job! Stay tuned........Ken

 

[jimmysisson]

Very entertaining, as you guessed, but what a drag, esp going into cold weather. Any ideas how the damage was done? Sounds more like abuse than neglect. Good thing the parts weren't more $, they seem cheap from wht I've seen.
Good luck with it and keep us posted.
Jim

 

[ruffdog]

It almost looks like the transmission case is cleaner than what is in front of it. Had it been worked on lately?

 

[TMB1320]

On the 4 wheel drive tractors, it always amazed how you could keep gears in them with different sized tires front to back. Truck transfer cases certainly don't like it especially on dry pavement. Not sure how tractors get around this. Do you know or maybe a TBN member with info might chime in?

Good luck with that. Looks like in for a penny in for a pound.

 

[Ken M]

Well, as I mentioned, there is more to the story. I looked on and off for about 3 years for something like this machine with a loader. Used is very hard to find at a reasonable price. This machine popped up in a dealer's lot and I took a look. It had been worked on. The story was that it had been traded in because of bad gears to FWD. Dealer repaired last winter when they were slow so yes the tranny was nice and clean. This was claimed to be a 9 x 3 but when I tested drove it did not go into low range. I walked away. I talked to a few other dealers and they all told me the same story...some of these tractors only had a 6 x 2 tranny in them and there was no way to tell except by a tear down. And some of the older guys had more to say. Most time you will never use the lowest range as it is too slow.

I eventually went back and drove it around. Ran good. Shifted good. There were some things that needed fixed. I harped about the low range and they didn't want to tear it down again so I made an offer as is and we made a deal. What they (and I) didn't know was that some mechanic hack had worked on the front axle much earlier. When I had the front differential apart I noticed some deep grind marks inside the LH axle casting. It looked like the bolts holding the ring gear had backed out and/or the the ring gear had broken. I suspect that there was damage to the housing and the cross shaft that broke as well. They put it back together that way. I imagine that they also broke the drive gears in the rear also but continued to use tractor in 2wd until they got tired of it and traded it in that way.

The best part is that the dealer took it apart and fixed the rear tranny and when they got done it was only a 6 x 3 not a 9 x 3. I've wondered now for a year how they did that...or was it really a 6 x 3 to start? Well now with this tear down I know.....There was an extra snap ring on the pinion shaft that wasn't supposed to be there. It restricted the sliding gear from it's full range and effectively turned a 9 speed into a 6 speed.

Transmission is off of tractor now. I have list of parts to order Tuesday ( from a different dealer) . Beside the 2 broken gears I will also replace 2 or 3 gears that have damage from shift grinding and a couple of gaskets and o-rings. Probably around $300 and $50 for the manual. It will take a few days to get parts...............Ken

 

[paine]

Wow, that looks like a serious job!

Not sure I would want to tackle that one myself.

Let us know how it turns out, are you planning on selling after the repair?

Good luck with the rebuild

 

[TractorTech]

On the 4 wheel drive tractors, it always amazed how you could keep gears in them with different sized tires front to back. Truck transfer cases certainly don't like it especially on dry pavement. Not sure how tractors get around this. Do you know or maybe a TBN member with info might chime in?

Good luck with that. Looks like in for a penny in for a pound.

To answer your tractor 4wd question. Ag tractors are designed with a front lead of 3-5 % so that the front is always pulling a little faster than the rear.
Overall, they are designed and should be weighted so that there is an approximate 15% slip factor of the tires, 2wd or 4wd, so as to find traction in soft soils. Too much weight/not enough slippage will cause the powertrain to bind causing damage. Likewise, it is not advised, as in a 4wd truck, to drive a tractor in 4wd on pavement or hard surfaces. The main difference in tractor transmissions and truck transfer cases is that the tractor drop boxes and transmissions are built much heavier to put up with normal stresses that a tractor encounters and is expected to endure.

 

[Ken M]

Fixed (at last)

Well this job took a while. Hard to get a block of time to concentrate on it. I had the tranny apart long enough that I was starting to worry that I would forget how I took it apart. I ended up replacing the two broken gears and two other range gears that were worn pretty bad. There was a third gear that I might have replaced but it was no longer available. I was able to hone the leading edges to remove some burrs and it will do just fine. So with parts, RTV, some spray cleaner, 5 gal of tractor fluid it looks like around $ 325. A bit less than the shop would have charged. It's all back together now including FEL and wheel weights. And everything works! Amazing!

I thought about a new machine as I worked on this. But now that I had the front AND back both apart I know what condition it's in (good) and with all the new seals it doesn't leak anymore! For my modest use I think it will be just fine....although those new hydro drives sure are tempting.

Now to get some winter fuel.

 

[tcreeley]

Well done!

 

[TMB1320]

Feels good when a plan comes together, eh! Work it gentle for longevity. Cheerios!

To T-tech: thanks for the reply. Didn't get email notice you replied, and forgot to check back until received
Ken's post. So the drive train front to back is designed to rotate at different ratio. I assume that makes
it important to keep the factory spec'ed wheel circumferences in order to minimize bind in the gear box.
Note to Ken; check your tire sizes, and maybe compare unloaded front to back rotation when 4wd engaged.