Charger 12 transmission

[Mgryder1 16]

I welded a piece in to fix the brake...turned out ok I reckon. Hopefully the part the gear milled off didn't destroy my pump.

[pfrederi 17,850]

I noticed in the video that he has to work to get his spring back in....and the picture you posted shows there is a gap between the ends (just as a spring should have). Mine almost butt together and my spring just falls into place...I can bend it open to make it fit tighter but what concerns me is why the heck its like that in the first place.  Also in the video he showed thrust washers...I dont think I have those and I don't see them in your pictures.

 

I took a better look at my "park paw" and there is a decent size groove taken out of the surface that meets the gear. Like its been milled out. I also found light metal shavings in the strainer/screen. That cant be good....the shavings are probably the parking paw. I have a mig welder so I'll fill in notch and grind it back smooth maybe tonight or this weekend. Ive still be unable to find that shaft seal (P/N:5959) but pulling the shaft will give me a good opportunity to visually inspect the seal. 

SKF 4911

[Mgryder1 16]

Thanks for the info. Do you know if this actually fits? When I pulled my brake lastnight I went ahead and pulled the shaft seal. I measured the 5959 seal to the just over 3/4" at 0.783". The OD of the SKF seal isn't wide enough according to the drawing.

[pfrederi 17,850]

I put the number you gave 5959 number in SKF cross reference it came back with Wheel horse and their 4911 number

http://www2.chicago-rawhide.com/popup_parts_lookup_457012.htm

[gwest_ca-(File Mod) 11,090]

Seal 1447 was replaced by 5959 and the only seal Wheel Horse used on a 1/2" diameter shaft that I can see.

 

Garry

[Mgryder1 16]

I'm waiting on a few seals to come in and then I can put this transmission back together, finally. In the meantime I made a new gasket...I put gasket material over one side of the transmission case used a ball peen hammer to tap around the edges and holes and a razor blade to cut it out. It turned out ok I think. I'll trim the area around the hitch later on.

[Mgryder1 16]

So I'm in my shop as I type this, I popped open part of the hydro and this is what I've found so far. I'm pretty much positive the brass pieces aren't supposed to be chewed up but I am not sure about the rest. The back of the "piston" piece seems to have a groove worn in and the same goes for the joining piece. Tell me what you guys think based on the pictures.

[Mgryder1 16]

Here's one more picture. Is there supposed to be an O ring there?

Edited April 8, 2015 by Mgryder1

[daveoman1966 3,757]

You have some work to do.  I looked closely at the brass piston slippers and they are trashed.  Their surface should be smooth and free of scratches / gouges.  The base of the cylinder that they are in is also trashed...deeply scarred.  What's more, the charge pump housing is also scored and needs refinished.  What you also need to do is remove the four bolts securing the charge pump[ housing to expose the gerotor set under it.  Be sure to mark the orientation of the charge pump housing BEFORE unbolting it.  I am certain that the gerotor set is scored similar to the other parts and they, too, will need refinished.  Not sure, but it seems you've not removed the THRUST WASHER that is in the pump housing.  The 9 piston slippers ride on this plate and it is likely to be scared as well.  That washer is hardened steel and only a precision grinder will removed the scars in it.

 

Before you start to put it back together, buy a little bottle of ENGINE ASSEMBLY OIL  Apply to anything that moves, as in these pics.

 

To answer your last question... NO, there should not be an O-ring in that gear-to-gear housing.   However, since you have opened it, be sure the bearings don't drop out on you (like it did to me). 

 

Here are a few pic to ponder....

ps...  I can only post a few pics on Red Square.  If you want more pics, send me an OFF-SITE email so I can capture your email address and return pics. 

[daveoman1966 3,757]

A few more pics:

I'm certain that the scarring on your parts is primarily from the chewed up filter screen.  It is also likely that some of it got into relief and flow valves on the base, accessible from the external ports.  You should have a look at them for broken springs and/or valves.  Here is what I found on the last one that I rebuilt.    

 

Edited April 9, 2015 by daveoman1966

[Mgryder1 16]

Thanks for the information, Dave. How did you refinish the scored pieces...chuck them in a lathe and face them off? If so, I have the capability to do that. I'll check for broken spring and valves when I get back on it tomorrow evening. As far as a chewed up filter...are you talking about the round screen that's about 1" in dia, 2.5"-3" long? If so, mine looked ok. There were metal shavings in and around it but I'm almost certain that was the brake paw that had been eaten.

[Pullstart 63,058]

I’m bringing this to the top, to point out how great of a post it is @daveoman1966!  I plan to look at a Charger 12 auto tomorrow and was just reading up on what I might be getting myself into... though I think the connecting rod’s broken and it has no trans issue so to speak of.

[Mgryder1 16]

Looks like I stopped posting Pictures once I got REALLY involved with rebuilding my transmission. I am happy to report that with Dave's help I was able to complete the rebuild and my tractor and transmission is still running strong 3 years later. I will try to go back to my archived photos this evening and post what all I did to get mine back up and going. 

 

Pullstart, I have a video of what I did to "bench test" my newly rebuilt transmission that I will try to post. Its really easy and may help you get a better idea of what your getting yourself into. 

[stevasaurus 22,841]

I have been looking for this post so I could put it in the Reference Section.  @Mgryder1 please post your videos and pictures.  @pullstart please add your photos to this thread also to fill in the holes.    Thanks for finding this thread.

[Pullstart 63,058]

3 hours ago, Mgryder1 said:

Looks like I stopped posting Pictures once I got REALLY involved with rebuilding my transmission. I am happy to report that with Dave's help I was able to complete the rebuild and my tractor and transmission is still running strong 3 years later. I will try to go back to my archived photos this evening and post what all I did to get mine back up and going. 

 

Pullstart, I have a video of what I did to "bench test" my newly rebuilt transmission that I will try to post. Its really easy and may help you get a better idea of what your getting yourself into. 

 

I might not ever need this, but it was too good to just let go.  I’m going to look at a Charger 12 that has a broken rod.... so no way to judge the trans condition on site than to trust the seller.

[953 nut 55,706]

3 hours ago, pullstart said:

I’m bringing this to the top, to point out how great of a post it is @daveoman1966!  I plan to look at a Charger 12 auto tomorrow and was just reading up on what I might be getting myself into... though I think the connecting rod’s broken and it has no trans issue so to speak of.

The greatest weak spot on the Sundstrand is the Acceleration Springs. If it has been driven hard and shifted from forward to reverse while at speed they will need to be changed out. Most of them have not been abused and will last for ever but new springs would be a good idea.

[Mgryder1 16]

OK guys, as promised I'm going to post my photos of what I did to fix my transmission. First, here is a video of how I "bench tested" my transmission. Ive seen all the suggestions about rigging up a belt to another tractor, and electric motor, etc etc...I came up with thiis, its simply a V-belt pulley on a shaft and I chucked the shaft in my battery drill. You have to run the drill in reverse if you stand on the side I was standing on. 

Transmission Test_Medium.mp4

[Mgryder1 16]

Some of my pics may be repeats but here Im trying to show that round disc thats about the size of CD. This disc was all scored up and it hardened so its difficult to fix without a surface grinder...I simply poped it out and flipped it over. 

[Mgryder1 16]

My transmission had a broken spring and its my guess that little pieces were cycled through the pump and thats how everything got so scored up. I dont know the name of all these parts and pieces so I'll do my best to explain what Im talking about. With that being said, Im trying to show the grooves (I circled one in red) that were cut into the oil filter looking piece. To get rid of them I purchased a manufactured tile from lowes and taped 120 Grit sand paper to it and did a figure 8 motion until a lot of the gouging was gone. I progressively went to finer grits 120, 220, 400,1200 until I got what you see on the right. It took a while.  

[Mgryder1 16]

I did the same figure 8 sanding patter on my "lowes surface plate"  on the brass slippers, these pull out individually. I wasnt able to get all the scoring out but I got most of it. 

[Mgryder1 16]

This piece is made of cast iron and my goal was to get rid of the grooves that I circled in red in the top left picture. I didnt know how to braze at the time so I just MIG welded a bead to fill them in. Dont give me any $hit about welding cast iron...keep in mind, my transmission works and yours doesn't  ha! I then chucked this piece in my lathe and faced off the welds. I only faced the welds down, not the cast iron surface. I then took this piece back the surface plate and did the figure 8 sanding like i did on the other pieces. 

[Mgryder1 16]

Same piece after final sanding on the surface plate. 

[Mgryder1 16]

Ultimately the broken spring and "plunger is what did my transmission in. I was able to find a new spring (part no. 7052) and I made a new plunger from a grade 5 1/4-20 bolt. There are two of the "plungers" and springs in the transmission, luckily only one of mine was destroyed which allowed me to measure the dimensions of the other one. 

Edited July 25, 2018 by Mgryder1

[Mgryder1 16]

This little piece was also boggered up pretty good. If I remember correctly, this what the springs and plungers stroke into. To fix this one, I just chucked it in the lathe and faced it off. 

[Mgryder1 16]

I hope these posts will help you guys. I could not have done this without Daves help and of course my equipment. If your transmission is torn up like mine was, you may need some of the same equipment. If I can help you guys with SOME of the lathe work I'd be happy to help. I am in the process of moving so I may not be able to get on it right away.