Front axle problems

[cda]

I've been hauling a lot of dirt over the past few weekends, and my trusty 4wd Hinomoto N359 just couldn't take the beating. It started to make some loud clanking noises which sounded like they were coming from the front wheels. The first time I heard it I was hauling a load down a hill, and for just a second, I heard a loud clanking noise and could feel the tractor shake slightly. I kept on hauling and noticed it a couple more times while turning sharp, or going up or down a hill. I'll also tried taking it out of 4wd, which didn't seem to be the problem because it still happened. During one of those noises I happened to notice the front left wheel lock up for a short period. That's when I pulled into the shop.

I started by taking the left wheel off, and continued to remove the gear case cover. Then I pulled off the steering arm, and lifted out the vertical axle drive gear. Basically, I'm left with the axle housing and shaft. I inspected all gears and bearings, they look perfect. The oil was pretty clean too, no metal shavings.






I'm hoping to get someone's recommendation on what to do next. Go to the other side and pull it apart like I did on this side or remove the axle housing and take a look at the differential? Should I be looking elsewhere, like the front drive gears in the tranny? Any help would be appreciated.


Also, now that I have the gear case off, I'm hoping to fix the leak that's been dripping down the tire since I got the tractor 2 years ago. Everything is out of the case, but I don't see a snap ring, or anything that looks like it's keeping the two parts together. Any ideas how to get these apart and replace the seal? The red arrow is the seam where the two parts meet.

 

[raptor749]

Just a thought , but check your 4x4 drive shaft universals & any hanger bearings if you have them .

 

[cda]

I don't have any u-joints, but there are two pillow block bearings on both ends of the front differential. I think I would have to drop the axle to get to them. Any idea how to get the drive shaft off? There is a 2 piece cover over the shaft. When I remove the hose clamp on the cover (looks like some one rigged that up. I can't imagine it's factory), one part of the cover slides over the other just a few inches. I can see a little bit of the shaft and the bearing when I slide it back.

Below are some pictures of the shaft cover and pillow bearings. Notice I removed the cover on the front drive control gears near the back of the shaft. Those gears look ok, from what I can see, but there were a few bits of metal stuck to the drain plug when I pulled out.

 

[cda]

I got the shaft off. I found another post with some details. I just slid the cover back, and used a punch to knock out a pin in the coupler, then it just slid on to the shaft, and I was able to pull it away from the front differential.

Now that I have the shaft off, I think I've begun to see where the problem is. The pinion is very loose, it wobbles up and down and side to side. I think the bearing might shot, I just hope there isn't any damage inside the differential.

My next challenge is to drop the front axle so I can open it up. I've removed the bolts on both the front and back pivot blocks (hanger bearings, pillow blocks, whatever they are called) but the axle will not separate from the frame. My only guess is that there are dowel pins between the pivot blocks and frame. It seems pretty crazy that those little dowels could hold up the weight of the axle. Any suggestions on how to get the axle off?

 

[cda]

I was able to get the axle off. I guess gravity is no match for 25 years of rust and two dowel pins.

After taking it apart, the problem is obvious. One of the taper bearings on the pinion has failed. I hope I can find a new bearing. Assuming that can be replaced, the only remaining problem is that the ring and pinion are damaged. As replacing those parts sounds fairly unlikely I was looking for suggestions in other threads. It looks like I have a few. Does anyone have a recommendation based on the pictures of the damage below?

1. Grind down any high spots and put them back in
2. Build up teeth with welder and shape with grinder
3. Replace them (I'm not even sure I could find the parts)
4. Remove entirely and live with 2 wheel drive