[Steevo]

Today I spent some time on the HT-20 project.
I cleaned and blasted the axle I will use to replace the original axle that was damaged beyond repair.

Then, after removing all bushings, I measured the axle pivot, PTO and spindle bores.

The center pivot was worn through one of the original bushings, and the axle hole slightly egg-shaped, so I decided to ream it out and use bushing with a larger OD:

Thankfully, I have a set of adjustable reamers that I picked up in a package when I bought a lathe several years ago.

I took the bores out to just under 15/16", which is the OD of the bushings I will use. When I get them, I will finish reaming the axle bores to a tight interference fit.

Next weekend, I should be able to get the frame steam cleaned and start working on it.

 

[kbtoy]

Steve, for your awareness the HT23S models had a 7/8" pivot shaft for the front axle and didn't use any bushings.
If you are willing to drill out the front axle bolster in the frame you could upgrade from the 3/4 to 7/8" pivot shaft at the same time.

HT23S also had needle bearings for the spindles instead of bushings.

You might ask how do I know this? I bought an HT23 front axle off ebay to repair one like yours and when it showed up it had these differences, so I did some parts book research and found the changes on the HT23S with power steering. In the end it made some nice upgrades to my 1886, but replacing the needle bearings for the spindles was expensive. I don't know if an earlier axle could be machined to accept these needle bearings?

Food for thought

 

[Steevo]

Steve, for your awareness the HT23S models had a 7/8" pivot shaft for the front axle and didn't use any bushings.
If you are willing to drill out the front axle bolster in the frame you could upgrade from the 3/4 to 7/8" pivot shaft at the same time.

HT23S also had needle bearings for the spindles instead of bushings.

You might ask how do I know this? I bought an HT23 front axle off ebay to repair one like yours and when it showed up it had these differences, so I did some parts book research and found the changes on the HT23S with power steering. In the end it made some nice upgrades to my 1886, but replacing the needle bearings for the spindles was expensive. I don't know if an earlier axle could be machined to accept these needle bearings?

Food for thought

That is interesting information, kbtoy.

Do you have the dimensional info for the needle bearings and axle bores to accept them? I'd be game for modifying mine if I knew what was involved.
The pivot is an easy one, and I may go ahead and use 7/8" shaft with bushings in the axle to fit it.

 

[bolens_kid]

Steve, for your awareness the HT23S models had a 7/8" pivot shaft for the front axle and didn't use any bushings.
If you are willing to drill out the front axle bolster in the frame you could upgrade from the 3/4 to 7/8" pivot shaft at the same time.

HT23S also had needle bearings for the spindles instead of bushings.

You might ask how do I know this? I bought an HT23 front axle off ebay to repair one like yours and when it showed up it had these differences, so I did some parts book research and found the changes on the HT23S with power steering. In the end it made some nice upgrades to my 1886, but replacing the needle bearings for the spindles was expensive. I don't know if an earlier axle could be machined to accept these needle bearings?

Food for thought

That is interesting because I have a HT23S. Never thought about that before. Was this on all large frames with factory power steering or just the 2389S model? I am going to dig into that a little more.

 

[Steevo]

After studying the parts books, it appears that they changed over to needle bearings on the 2389 after serial number 199999 and then on all 2389S models as well. Now I need to find out what the specs are on those bearings.

 

[Cakes]

It looks as though the flange bearings and the needing bearings for the spindles have the same specifications. The OD of both (without the flange) is 1-1/4" and the ID is 1". I think these could be interchanged without issue. The axle pivot would need to be machined.

 

[jajaid6]

love pictures.great work!!

 

[Steevo]

It looks as though the flange bearings and the needing bearings for the spindles have the same specifications. The OD of both (without the flange) is 1-1/4" and the ID is 1". I think these could be interchanged without issue. The axle pivot would need to be machined.

Yep. I found some 1.25" OD x 1.00" ID x .75" needle bearings on McMaster Carr's website. What I am wondering is how they secured the needle bearing in the bore with no flange to keep it from migrating.

 

[kbtoy]

Looking back at my notes I used MMC 5905K28 needle bearings for the spindles.

This needle bearing came with an outer race that pressed into axle. If memory serves me correctly I pressed them in until they stopped against a shoulder

An axle that originally had the plain bushings with the flange may not have the shoulder, but there is no reason you couldn't make a spacer to go between the upper and lower needle bearing as long as its ID was large enough to not touch the spindle. This would keep the needle bearings located.

I believe the late HT23S also had needle bearings where the steering shaft goes into the steering bridge and in the pivot for the steering sector gear. I haven't tried to recreate these as I switched to hydrostatic power steering with a handpump which eliminated these 2 pivot points.

 

[Steevo]

The spacer idea is a great one. That is how motorcycle hubs are done, to keep the bearings from being squeezed inward when the axle is tightened.
I think I'll add four of the needle bearings to my next MMC order and see what I can come up with.

 

[Steevo]

I have made a little progress on my HT-20 project.

My brother in law really came through for me, getting permission for me to bring my frame to his place of work to use their steam cleaner to degrease it.
Some before and after shots:

Then I started disassembling it.
I drained the differential:

The fluid was clean and clear with no signs of moisture or debris, and the magnetic drain plug had almost no filings stuck to it.
The bull gear feels tight, with almost no rotational play between axles.

I knew that there was a worn area where someone had run the rear PTO drive shaft with an incorrectly mounted tiller.
Once I had it cleaned up, it is easy to see just how badly worn it is:

Amazingly, it does not appear to be worn through anywhere, but I am thinking I'll weld it up and grind it smooth anyway just for peace of mind.

I pulled the hubs and brake calipers, and dangled the axle over my parts washer so I could scrub off the last remaining gunk where I missed it with the steam cleaner. It looks pretty good now:

I think I'll replace seals on the axles, and probably the hydro shafts as well, since I don't know where all that oil on the outside was coming from.

Then I dropped the front axle:

I will tear it down completely, and check the spindles to see if they are badly worn or can be re-used in the axle I am building for this tractor.
The center pivot shaft was tight and the frame holes not worn, so I think I'll go with stock pivot shaft and bush my replacement axle down to 3/4".

 

[bobbybats]

Nice job Steevo. I need to gets me one of them steam cleaners. They sure work nice!

I have wear on my axle like yours from the rototiller shaft so will be intersted in how you repair yours. These axels are cast iron correct? I know cast is a Beoch to weld without cracking. Preheat, weld, controlled cooling. Some guys bury it in dry sand after welding and let it cool for a few days. Do you think it can be done with the transaxle assembled or are you planning to strip that down as well?

I was thinking I would fill it with braze? Some of the braze has crazy tensile strength. Something like 60,000 psi I recal. But I am not sure about abrassion resistance. I'm just a back yard welder but try to learn as much as I can.

I guess you could always build it up higer than stock to account for rototiller shaft wear on the axle. Or better yet mount it right in the first place. Tho mine seems to rub no matter how I mount it (pin in the ears placed in lowest hole/closest to the ground).

PS Im stealing your roller idea. My tractor time is usaly in short stints and garage space is at a premium. Roll it out to work on it. Roll it back out of the way when I need space.

keep up the good work!:trink39:

 

[Steevo]

I am not sure yet which welding process I might try to fill in the axle wear. I am thinking of stick welding for cast iron.
From what I have seen, I believe that if the tiller is properly hooked on the lower 3/4" pins, and the 5/8" pins are installed above it, it should not be able to climb up and push the drive shaft against the axle.

 

[LPBOLENS]

...............I believe that if the tiller is properly hooked on the lower 3/4" pins, and the 5/8" pins are installed above it, it should not be able to climb up and push the drive shaft against the axle.

According to the manual for the 18093 tiller, that is the correct way to mount the tiller. With the various manuals available for download, I have always felt that it is inexcusable for anyone to only guess at how the manufacturer intended the attachments to be mounted.

 

[Steevo]

Today I disassembled the HT 20 front axle.
Unfortunately, the spindles are excessively worn in the "usual"places:

Fortunately, I have a pair of spindles from a QT that are in much better condition:

Unfortunately, the QT spindles have the key-way cut into the side opposite the axle, while the HT has them at 90 degrees to the axle:

Fortunately, I was able to mill some new key-way slots in the 90 degree location, making the QT spindles work for the HT:

I also discovered that the steering bridge on the HT 20 has a big chunk missing from the front-right corner:

This may not be an issue, since I am planning to convert this HT to power steering, and the bridge will not need to host a steering gear. I may fabricate a new bridge that simply anchors the lift cylinder, and has no provision for the steering gear at all.

 

[wilberj]

According to the manual for the 18093 tiller, that is the correct way to mount the tiller. With the various manuals available for download, I have always felt that it is inexcusable for anyone to only guess at how the manufacturer intended the attachments to be mounted.

Some still hit a little mine does.

 

[wilberj]

Those spindles can be fixed I have a way to fix them at my work.

 

[Steevo]

Those spindles can be fixed I have a way to fix them at my work.

I'd be interested in hearing about how you fix them.
I have a few pair that are badly worn.

 

[LPBOLENS]

Some still hit a little mine does.

But I would bet you went to the trouble to try to have a manual for everything you own. Didn't you, Jerome? I know I have.

 

[wilberj]

But I would bet you went to the trouble to try to have a manual for everything you own. Didn't you, Jerome? I know I have.

I have stacks and stacks of paper work! I got around 16 inches of paper from the factory engineering department of Bolens that bust down changes in models from the early 70s up to the 90s. Best part it brakes down changes in the tractors to like what change in the 2389-01 to the 2389-02.


I got around 50 hours on my 1476 with the 48 tiller on it in the last two years. The tractor had no mark in the rear axel when I got it but it does now from the drive shaft I think it from slop.