So I did a thing... Agria 8900D

[ptsg]

Yes I think I follow. I like the groove idea to provide space for the locktite. What I wasn't clear on is if you machined a surface in the oil passage portion of the casting parallel to the filter seat for the insert to seat up against and provide for axial loading or if the insert is only being held suspended by the press fit OD?

Hopefully it will hold with the additional filter edge clearance cut as you mentioned. It occurred to me that if it does leak sometime down the line that groove for locktite could be replaced with a thin oring around the OD of the insert to allow for some flex.

Nice work and thanks much for sharing!

I did machine the surface as you said, so the ring bottoms out on a machined surface on the filter housing.

 

[ptsg]

In the last couple of days, I've pulled the rear gearbox out and started going through it. Found 3 bad bearings and seals and found out that it has surprisingly big gears for the PTO. Wasn't expecting that.

Both brakes had one broken shoe that got repaired on each side for some reason. Not sure what would've caused that. At least they were relined at some point, so I just need to clean those out and put it back together.

The shift rails had lots of rust as I said previously but also the plunger was so wore out that it didn't even have a point anymore to sit on the holes of the rails. Also, both springs were rusted and broken. Couple more things to fix.

Spacer/4WD selector. Has one bad bearing and looks like two bad seals.

Rear left side brake, axle and final drive:

PTO pictures. On this one, a needle bearing gave out and damaged the shaft (2nd) picture. Since the needles ran on the hardened shaft and while I can build the shaft back up, I can't recreate the hardness of it so I may replace this bearing with a bronze bushing instead. Still debating on that.

One thing I'm liking in this tractor so far is that it pretty much uses just off the shelf parts, like bearings, seals, pins, etc. Nothing proprietary to the manufacturer.

 

[etpm]

In the last couple of days, I've pulled the rear gearbox out and started going through it. Found 3 bad bearings and seals and found out that it has surprisingly big gears for the PTO. Wasn't expecting that.

Both brakes had one broken shoe that got repaired on each side for some reason. Not sure what would've caused that. At least they were relined at some point, so I just need to clean those out and put it back together.

The shift rails had lots of rust as I said previously but also the plunger was so wore out that it didn't even have a point anymore to sit on the holes of the rails. Also, both springs were rusted and broken. Couple more things to fix.

View attachment 840896 View attachment 840897

Spacer/4WD selector. Has one bad bearing and looks like two bad seals.

View attachment 840898 View attachment 840899

Rear left side brake, axle and final drive:

View attachment 840900 View attachment 840901

View attachment 840902 View attachment 840903

PTO pictures. On this one, a needle bearing gave out and damaged the shaft (2nd) picture. Since the needles ran on the hardened shaft and while I can build the shaft back up, I can't recreate the hardness of it so I may replace this bearing with a bronze bushing instead. Still debating on that.

View attachment 840904 View attachment 840905

One thing I'm liking in this tractor so far is that it pretty much uses just off the shelf parts, like bearings, seals, pins, etc. Nothing proprietary to the manufacturer.

There are welding rods that can be used to build up that shaft that will be plenty hard enough. But then you would need to grind it to size, also, the size would need to be very exact. One option could be to use a hardened bushing that is a press fit or a shrink fit onto the shaft. Once again the size needs to be controlled exactly. The shaft could be turned to a .00254 interference fit with a couple grooves about 1mm long and .07mm deep. The grooves would be for some Loctite. I think 609 is the right number. If you decide to use a bronze bushing I would suggest aluminum nickel bronze alloy. This alloy excels in high load situations. It will tolerate low lube situations better than many other bearing bronze alloys. It is quite slick. However, if oil starved for relatively long periods it will tend to wear less than the steel shaft running in the bushing.
Eric

 

[ptsg]

There are welding rods that can be used to build up that shaft that will be plenty hard enough. But then you would need to grind it to size, also, the size would need to be very exact. One option could be to use a hardened bushing that is a press fit or a shrink fit onto the shaft. Once again the size needs to be controlled exactly. The shaft could be turned to a .00254 interference fit with a couple grooves about 1mm long and .07mm deep. The grooves would be for some Loctite. I think 609 is the right number. If you decide to use a bronze bushing I would suggest aluminum nickel bronze alloy. This alloy excels in high load situations. It will tolerate low lube situations better than many other bearing bronze alloys. It is quite slick. However, if oil starved for relatively long periods it will tend to wear less than the steel shaft running in the bushing.
Eric

Thanks for all those suggestions. I'll see what I can find regarding the welding rods. I could rig a die grinder on the tool post and grind it to size if needed.

As far as oil starvation, that bushing will be under the oil level 100% of the time. That's why my first idea was the bushing. A couple grooves for the oil to flow in and should last a decent amount of time.

The shaft will only spin on the bush in the 540 PTO gear. If I use 750/540E, it's a direct drive on this area and the shaft spins at the same speed of the bushing.

 

[MTGreen]

Thanks for all those suggestions. I'll see what I can find regarding the welding rods. I could rig a die grinder on the tool post and grind it to size if needed.

As far as oil starvation, that bushing will be under the oil level 100% of the time. That's why my first idea was the bushing. A couple grooves for the oil to flow in and should last a decent amount of time.

The shaft will only spin on the bush in the 540 PTO gear. If I use 750/540E, it's a direct drive on this area and the shaft spins at the same speed of the bushing.

I've done that die grinder on the tool post trick several times with various rigid adapters and my experience has been that you don't get results like a real tool post grinder because you are limited by the die grinder bearings which tend to be on the loosey-goosey side in the runout department (probably deliberate to deal with grinding dust). I've found it works in some applications that you only need +/- 0.001-0.002" for it to work, but as etpm mentioned above you'll need a very exact fit here and unless you have an exceptional high precision bearing die grinder I'm thinking you're not going to have much luck. Of course YMMV

 

[ptsg]

I got sick right after Christmas, so progress was a bit slow. Still cleaned all of the rear gearbox parts. replaced one bad bearing, fix all the detent parts for the shift rails and fixed the damaged shaft for the PTO. Ended up just building the diameter back up and turn back to 16.00 mm on the dot. Will go with the bronze bushing route and see how long it lasts.

Got a little bit of an update on the head. He sent the head to a welder which said he didn't had enough space to fit the torch and fill the hole that the valve put on the exhaust port. But the engine shop guy says he can deal with the other damage no problem. I can deal with the hole, so that's fine and the head will be fixed. I also gave him a new set of valves and guides. Maybe this week I get it back, probably won't though.

Picture of the detent parts for the shift rails. I went ahead and pressed a ball from a bearing on the plunger, found two new springs and modified the set screw slightly. Also, using an air tool, I cleaned the detent dimples on the shift rails.

Pictures of the shaft I fixed and most of the gearbox put back together.

 

[2manyrocks]

Hope you get to feeling better. Good to watch your progress.

 

[ptsg]

Got the PTO gearbox all ready to go. Cleaning all the milk oil, wash all the parts and put it back together with a generous amount of grease on just about everything inside.

I don't know when this thing will be put back together in running condition, so I'm trying to prevent any rust from forming till then. I'm using a mixture of kerosene with paint thinner to wash all the parts and this leaves no protection against rust.

This is where that needle bearing failed. I was going over my bronze stock to machine a new bushing and lo and behold, I found just the bushing I needed. A sintered bushing 16 x 20 x 25 mm. Exact ID and OD I need, just 5 mm too long. No big deal, chuck it in the lathe and machine it down. Sure it's nice having something going my way for once.

I can now attach the PTO gearbox back to the rear main gearbox. It's only missing the seals, which I have already ordered all the seals for the entire tractor. Pretty much any oil seal on this tractor can go in with everything assembled, so I can leave those for last.

On this PTO gear box, direct drive is 750 PTO RPM or 540E. Going through the gears is 540 RPM. Technically, using 750, means that the bushing will have no wear at all since both shafts spin are coupled together. This is for the bottom PTO shaft, which is the standard 1 3/8" 6 spline shaft.

The top PTO shaft is 1 1/8" 6 spline shaft and spins all the time the engine is running, with no way to disengage it. It outputs 640 RPM at 3000 engine RPM in Low Range and 1000 RPM in High range.

 

[MTGreen]

You really bought a basketcase but by golly you're making it come together. Kudos to your tenacity and skill set. Looking great and thanks again for sharing

 

[ptsg]

You really bought a basketcase but by golly you're making it come together. Kudos to your tenacity and skill set. Looking great and thanks again for sharing

This one is turning out to be quite a basketcase. Not sure if I won on this one. Just about everything I take apart, there is something wrong with it and I still have the front half and steering box to pull apart.

I guess I got lucky on my crawler tractors and generator I bought for dirt cheap. Those required minimal fixes, just a nice clean up and paint job for the most part.

Anyway, I still have less than €800 on it and it's still worth more than that in parts. I'm stubborn and I refuse to throw the towel, yet...