Stahl dozer gear boxes and drive motors

[rc13]

Hello, I have started a project on my Stahl Dozer. I am making a couple of repairs and changing a couple of other things.

The main component that I am working on now is a gearbox for on of the motors. One of them went out last year (gear stripped). I didn't think that I would be able to find just a gearbox replacement, so I started on the path of just replacing both the gearbox and motor on both sides.

Last summer I asked Ric from PMD if he had the replacement gearbox or if he could get them. He suggested to just get a couple of new motors/gearboxes.

I bought a couple of them not too long ago and just started on the replacement yesterday. I thought it would be a pretty simple fix. but the new motors/gearboxes do not match up properly.

There are a lot of little differences that would have to be modified to accommodate new motors and gearboxes. The little differences would need a ton of mods to make it work. I just don't want to take the chance of screwing up something. Also I don't want to spend a ton of time doing so.

I called Ric from PMD again and he thought that at some point not too long ago, he knew of someone else that was trying to replace a gearbox on this same type of machine. He was going to try and remember what that person did to remedy the situation with the correct replacement parts.

To me, I am assuming there is a lot easier solution that is less risky than me modifying the existing dozer parts to accommodate a new motor/gearbox.

I have not heard back from Ric and I am not sure how long that will take for him to find out, so I thought I would as on here to see if anyone has any suggestions.

Thanks,
Eddie

[rc13]

Hello, I have started a project on my Stahl Dozer. I am making a couple of repairs and changing a couple of other things.

The main component that I am working on now is a gearbox for on of the motors. One of them went out last year (gear stripped). I didn't think that I would be able to find just a gearbox replacement, so I started on the path of just replacing both the gearbox and motor on both sides.

Last summer I asked Ric from PMD if he had the replacement gearbox or if he could get them. He suggested to just get a couple of new motors/gearboxes.

I bought a couple of them not too long ago and just started on the replacement yesterday. I thought it would be a pretty simple fix. but the new motors/gearboxes do not match up properly.

There are a lot of little differences that would have to be modified to accommodate new motors and gearboxes. The little differences would need a ton of mods to make it work. I just don't want to take the chance of screwing up something. Also I don't want to spend a ton of time doing so.

I called Ric from PMD again and he thought that at some point not too long ago, he knew of someone else that was trying to replace a gearbox on this same type of machine. He was going to try and remember what that person did to remedy the situation with the correct replacement parts.

To me, I am assuming there is a lot easier solution that is less risky than me modifying the existing dozer parts to accommodate a new motor/gearbox.

I have not heard back from Ric and I am not sure how long that will take for him to find out, so I thought I would as on here to see if anyone has any suggestions.

Thanks,
Eddie

few more pics

[rc13]

If I was to mount up the motors, with the round motor mounting plate thickness in combo with the slight thickness of the sidewall of the dozer chassis, by the time I get the gearbox mounted then the spur gear on the motor is more recessed, therefore, the gear mesh would only be about half (so in a nutshell, the half of the motor gear would only be meshing with half of the gearbox gear)...

The newer motor / gearbox is to mount on the outside of the gearbox housing. The original motor/gearbox for this dozer mounts between the motor and gearbox housing.

Also the sprocket gear for the tracks has a large hole that has a locking pin that slides through the motor shaft. The collar that is between the gearbox and the shaft of the new motor is too big to fit inside of the hole of the sprocket.

[rc13]

https://www.flickr.com/photos/146664594@N05/shares/d6i05c
https://www.flickr.com/photos/146664594@N05/shares/6607GA
https://www.flickr.com/photos/146664594@N05/shares/93vWto
https://www.flickr.com/photos/146664594@N05/shares/MC1Gvw
https://www.flickr.com/photos/146664594@N05/shares/f0szm2
https://www.flickr.com/photos/146664594@N05/shares/67yXfN
https://www.flickr.com/photos/146664594@N05/shares/Z60xq9

[Lil Giants]

Can you change just the stripped gear itself in the oem gearhead with one from the new gearhead/motor?

Smallhaul has worked alot of these Leimbach/Stahl models, I'm sure he has some good advice & maybe some spare parts too to get you going again. ;)

My dozer & track loader motor mounting is different as they were 2002 model years.

[rc13]

Can you change just the stripped gear itself in the oem gearhead with one from the new gearhead/motor?

Smallhaul has worked alot of these Leimbach/Stahl models, I'm sure he has some good advice & maybe some spare parts too to get you going again. ;)

My dozer & track loader motor mounting is different as they were 2002 model years.

Hi, thanks for the suggestion. Much appreciated... I thought about the gear replacement. The way the gearbox is pressed together worrries me a little. If it was screwed together it would be no problem. But it is pressed together somehow. There is probably a technique, tool, or machine for it. But that is something I am not familiar with. I wouldn't mind repairing the gearbox. Those small motors are amazingly powerful. But, if I have an issue again, then what... So, I am leaning towards new motors/gearboxes. But at this point, I will do what I need to to get it up and running.

I just inspected the gearbox. I did find the gear that was stripped. I also figured out why it stripped. The shaft that holds the gear is a tad loose where it mount to the outer round plates of the gearbox. The holes that the shaft go in are a little bit reamed out. So the shaft is not spinning in a stable position. The shaft is wiggling... So the holes that the shaft are in are worn:(. See the pictures below... Now that I see that, the gear replacement just will not work.

Scott from Smallhaul, if you see this, do you have any suggestions?

If I don't hear from Smallhaul I will contact him.

Or does anyone else have any thoughts or suggestions?

Thanks!

[rc13]

https://www.flickr.com/photos/146664594@N05/shares/4k3SZh

[Northern Farmer]

Here you go ;)

http://www.conrad.com/ce/en/product/227579/RB-35-1200-gearbox-motor?queryFromSuggest=true

http://www.rctruckandconstruction.com/showthread.php?p=126883

http://www.gardentrucking.com/pdf/PMDStahlBrochure.pdf

[Northern Farmer]

Also found this, I'm not sure if it would work on your Stahl dozer ?

http://store.rc4wd.com/DXR2-Dozer-Drive-Motor-and-Gear-Assembly-Set_p_5124.html

[rc13]

Here you go ;)

http://www.conrad.com/ce/en/product/227579/RB-35-1200-gearbox-motor?queryFromSuggest=true

http://www.rctruckandconstruction.com/showthread.php?p=126883

http://www.gardentrucking.com/pdf/PMDStahlBrochure.pdf

Hi, wow, thanks for the help. I checked out the first 2 links about the gearbox/motor. I do have the exact motor that you suggested.

https://www.flickr.com/photos/146664594@N05/shares/26zqju

I see that that other guy that had a problem with his dozer, he had a burned out motor and just replaced the motor an not the gearbox. If my gearboxes were good, the motor swap would be pretty simple. But it is the weird set up of the gearbox/motor attaching to the chassis of the dozer in between the motor and gearbox. The existing gearbox is nothing I have ever seen. So nothing will line up.

After reading the thread that you provided, the other person was talking about something on the pinion gear and that gave me an idea. If you read some of my earlier thread, I mentioned that if I was to get this mounted, the gear mesh would not be a full mesh. So my idea was to slide the pinion motor out a tad, maybe a 16th of an inch. Then there would be a better mesh. If I did so, since is so small and there is not a grub screw to tighten the pinion gear to the shaft, would I use a some type of adhesive to adhere the pinion gear back to the motor shaft?

https://www.flickr.com/photos/146664594@N05/shares/980YSE

Thanks

[rc13]

Also found this, I'm not sure if it would work on your Stahl dozer ?

http://store.rc4wd.com/DXR2-Dozer-Drive-Motor-and-Gear-Assembly-Set_p_5124.html

Hi again, another great suggestion. Those motor drive sprockets look great. I am sure plenty of power. They appear that they might mount up. For sure the sprocket teeth are way different, so I would have to mount mine to that motor set up. If I could only see what that looked like with the sprocket off....
Hopefully I can find another solution for a lot less that the 500 USD. :D
Thank you so much......

[Northern Farmer]

Found this website maybe they have the parts you need.

http://www.tankmodel.com/1_14_5_scale_german_made.html
tankmodel@126.com

[rc13]

Found this website maybe they have the parts you need.

http://www.tankmodel.com/1_14_5_scale_german_made.html
tankmodel@126.com

Hi, thanks again. I sent that contact email a message..

[Rimrock]

I'm not familiar with if possible Stahl used different motor options for the dozer, but I have just supplied a customer with new RB35's, which he had originally in his dozer. 69 rpm, not know what ratio. I guess the 'RB35' refers to a industrial standard gearbox housing, and there are some different ratios, and slightly different motor sizes, powers. On the mentioned dozer, we went for some RB35's with stronger motors, which made the motor a bit longer, but still not too long to fit

[SmallHaul]

Eddie, in my box of gears i had long pinion gears that were long enough to reach. If you search the net you should be able to find some. You only need about 2mm of shaft in the gear to hold it well because there is much less torque/stress applied on the pinion than on the gears further out in the gear train. clean the shaft and gear well with rubbing alcohol. Place a drop of original JB weld on the pinion before you push it on and let it sit for 24hrs before you touch it again. Good luck and have patience.

[rc13]

Ah yes!!! It looks like you had a similar fix project. I will find and buy some of those. I am also looking to purchase some time. I would like more hours in the day. LOL...
Anyway, thanks for your help as well. I will reply back when I get this dozer repaired.

[rc13]

I just got around to ordering some longer 10t pinion gears. So, I will once again push this project off to the side until the gears come in. I also started taking the other side of the dozer apart so that side can be replaced also. My dozer is a little funny looking on the bench. A lot parts in a box and mostly just the chassis sitting there.

https://www.flickr.com/photos/146664594@N05/shares/9qrYn8

[rc13]

I looked all over the place for the correct pinions needed for this mod... I bought some pinion gears from a few diff. suppliers. One set wasn't quit long enough and the other set had a tad too big of a diameter. Couldn't get answers from them prior to purchase, so I took the chance and bought them anyway. They were only a few bucks.

So, I talked to someone at SDP/SI (Stock Drive Products / Sterling Instrument). I gave him the exact measurements. The rep directed to me to the parts on their site where I could purchase some pinion stock. It is sometimes nice to get live help over the phone instead of by email.

https://www.flickr.com/photos/146664594@N05/shares/78471Q

So I bought 2. They are what I was looking for. Now I can just cut them to the correct length. Oh, and drill the 2mm bore. I better do that first..

Also, I going to see about getting the original gearbox repaired.

[SmallHaul]

That is great that you found the gears. I wouldn't drill the gear out to 2mm because you want a pressed/interference fit. Make the hole .002 (two thousandths) smaller than the shaft and press the gear on.

It is best to practice on similar material making the interference hole because when you drill the hole it will often be larger than the size of the bit when you measure the shaft. Drilling a hole accurately to the thousandths of an inch is a bit of an art (pun intended).

A good read:

https://www.quora.com/Machining-If-I-drill-a-hole-with-bit-diameter-x-what-is-the-diameter-of-the-resultant-hole

What i have found that works well is to make a pilot hole about .01 (ten thousandths) smaller than your final hole size and then allow the part to cool and then run the final bit size through it.

[rc13]

That is great that you found the gears. I wouldn't drill the gear out to 2mm because you want a pressed/interference fit. Make the hole .002 (two thousandths) smaller than the shaft and press the gear on.

It is best to practice on similar material making the interference hole because when you drill the hole it will often be larger than the size of the bit when you measure the shaft. Drilling a hole accurately to the thousandths of an inch is a bit of an art (pun intended).

A good read:

https://www.quora.com/Machining-If-I-drill-a-hole-with-bit-diameter-x-what-is-the-diameter-of-the-resultant-hole

What i have found that works well is to make a pilot hole about .01 (ten thousandths) smaller than your final hole size and then allow the part to cool and then run the final bit size through it.

Good point about drilling the hole .002 smaller for the finished hole. I will do that. The true measurement of the motor post with my caliper is 1.96mm. I definitely don't want that slipping...

I usually drill holes with a little smaller bit than my finish bit, but I will definitely do that on this.

I think it will work out well. I just need to get too it.

Thanks!