1990s 520H Transmission Swap

[Dylan2342 11]

New here! hello everyone! In a bit of a pickle here. My father owns a 1993 (I think that is the right year) 520H Wheel Horse. I don't commonly work on tractors but it seemed simple enough. the axle snapped on the left side, so it needed a new transmission. My dad bought a used transmission and I went to work changing everything out. The hydraulic pump that the engine's drive belt attaches to went to a different model/year of tractor, so I had to remove that part and swap it in from the old transmission. In the process I lost all of the oil in the pump (I mention this because I wonder if it has to do with my problem I'm having). When I reassembled everything I started the slow process of filling the transmission. I filled it up and started the engine. When moving the lever forward or backward, it had a tiny bit of power for a little bit and then lost power. The transmission wasn't doing anything, anymore. I though maybe that hydraulic pump needed to be primed, so we took the top hydraulic line off of the hydraulic pump right above the drive belt and used a transfer pump to pump some oil into the pump case. This still didn't work. I don't have enough experience with these hydrostatic transmissions to know if we got a bad transmission or if there is something obvious that I am missing when it comes to a transmission swap. I ask for any insight and help please. If you need pictures or any other info, then let me know what you need. Thank you!

[Pullstart 62,698]

 I sure hope the transmission didn’t fry being filled back up.  I am not a 520 guru however…

[Achto 27,481]

 

Could we get a picture of both transmissions? I'm a little confused about you having to swap pumps. I thought that all 520's had an Eaton 1100 transmission. 

 

Other things to check would be the fluid level on the dip stick. Could also be a clogged hydro filter. Correct filter WIX 51410 or Napa 1410.

Edited February 9, 2022 by Achto

[lynnmor 7,294]

Photos of both transmissions would help, we can’t follow the process.  Why didn’t you just replace the axle?

[Dylan2342 11]

Gathering pictures now. the way the axle split we were worried about damage to the case as well. it was still functioning while  just dumping oil from where the axle exits the case.

[Dylan2342 11]

[Dylan2342 11]

I am not able to  upload any other pictures. I guess I'm limited on data upload.

[Dylan2342 11]

I could consider the filter. I didn't want to put a brand new oil filter on this used transmission because I wanted to change the transmission oil after about a day or so of use to try to give it the best, cleanest start possible.

[Handy Don 12,088]

I, too, would be interested in seeing the damage to the original transaxle. Was the case cracked or was it just the axle and maybe bearings?

 

Do you have the Eaton manual and transaxle manuals? I've attached links to the downloads here.

The upload picture limit goes away if you join as a supporter (go to the Store topic).

The charge pump draws from the reservoir (i.e. the transaxle sump) and as long as there was enough oil in the pump to let it operate without binding, it should prime itself. My biggest worry is that during the swap when removing or installing hoses some dirt or other contamination got into the pump/motor. While Eatons are strong and made to last, they have extremely tight tolerances and any abrasive dirt or grit can mess one up in no time.

Give a good read to the manuals.

 

 

Edited February 9, 2022 by Handy Don

[roadapples 6,983]

[Dylan2342 11]

Here you see the axle split. whatever happened caused it to gush out oil from the seal here. The axle was discontinued so we opted for just getting a used transmission and swapping it out.

[Dylan2342 11]

Here is the old transmission next to the hyrdraulic pump from the "new" transmission. The linkage and the hydraulic lines didn't fit our tractor.

[lynnmor 7,294]

There was a change from rubber hose to steel lines about 1992, I don't know if that is what you are dealing with.

 

Why not split the case and pull the axle, you have nothing to lose?

 

An axle broken in that fashion comes from loose set screws allowing the hub to work the key till it is broken.  You have an extreme case of that and the hub will be wasted as well.  Do not reassemble with parts that don't fit well or the problem will return.

[Handy Don 12,088]

Pictures help. Your "new" pump/motor is an Eaton 7 (aka 700). WH used these on 518-H and 312-A models, and some others. The pump/motor used on the 520-H is an Eaton 11 (aka 1100). These are not direct replacements and that may be the root of some of your issues.

 

As you've already discovered, the actuator cams are in different places so the linkages align differently. Also, the attachment to the transaxle requires an adaptor shell for the 700 and not for the 1100.

The 700 does NOT circulate oil to the transaxle, it is self-contained with a small expansion reservoir on top (the reservoir attaches to that rubber tube coming out the top). It must have the reservoir attached and the reservoir must be filled prior to operating the pump/motor manually before connecting it to the engine (see the manual here).

The 700, because it is self-contained, does not have a external oil filter for circulated hydro oil.

The 700 does NOT have a charge pump, so there is no capacity for external hydraulic lift.

The 700 can deliver up to about 7 horsepower to the transaxle, regardless of engine horsepower. The 1100 can deliver up to about 17 horsepower. Hence the 700 is perfectly fine for mowing, blowing, and light towing but not ideal for the plowing or heavy towing that the 1100 can handle.

Edited February 9, 2022 by Handy Don

[Dylan2342 11]

@Handy Don 

This is a lot of good info, thank you. So because things didn't match up right I did take the 1100 off the old transmission and put it into this "new" transmission. I made sure to take the fittings and sensor from the old and put it into the new as well. I start my work week now and won't really be able to get into the tractor until next week. I appreciate all the valuable input I've received so far though. If anybody wants specific info or pictures that I haven't already provided/ haven't given enough clarity to, then please let me know in the mean time. Thank you. 

[Jeff-C175 7,199]

5 minutes ago, Dylan2342 said:

info

 

I'm a little surprised that no one has mentioned our "Vendor Section" 

https://www.wheelhorseforum.com/forum/92-vendors/

 

These guys each have their own 'niche'.

 

You could likely get a good used axle and hub from A-Z Tractors.  Lincoln is a great guy and has well... everything.

All the others are equally good, but A-Z is probably the best for used good parts.

 

 

[Dylan2342 11]

I figured I would post an update. I decided to take the hydraulic pump and tear it apart and put it back together. I used the manual and this video. everything looked good. When I test ran it, it seized up after about 3 minutes of trying to get it to move forward or backward with no success. I am going to have to tear it apart again to see if there is a seized bearing or if it became clogged from oil from the "new" transmission. I hurt my back, though, so I am taking a small break from the project.

 

Eaton 11 Rebuild.pdf

[davem1111 2,027]

I was about to post a question about my 312-A hydro, and maybe a new thread would be wise, but I think I'm on topic here.

 

My 312-A which I now understand uses the Eaton 700, had been leaking fluid and not moving the tractor much, if at all. It sat for several months, then I filled the reservoir and if anything, it's even worse now - won't move at all. Verified that the belt isn't slipping, etc.

 

So I'm debating whether I should try to get a new Eaton 700 pump or just replace the whole transaxle. Will a 520-H transaxle fit on a 312-A without modification?  I think I saw one (the whole thing, used) for sale. I also saw a 416-H transaxle, which looks just like the 312-A with the Eaton 700.  FYI, I also have a 416-8 that I bought last fall that works but needs some TLC. I thought about converting the 312-A to a shift but 1) would like to keep it original, and 2) would like to have one shift and one hydro. 

 

Does it sound like just replacing the Eaton 700 is the best approach?  I don't really want to spend $300-500 and not solve the problem.

 

To the OP here, it sounds like trying to find a used axle/hub would be a good route to take, and if you've ended up with an "extra" Eaton 700 pump I may be interested in buying it. 

 

Thanks!

[davem1111 2,027]

Anyone know if a C175 transaxle (entire assembly) will fit on a 312-A?  If so, any challenges with drive belt/idler/pulley or wheel height and fenders, etc.?  I may be able to pick one up for about the same cost as a used Eaton 700, and with this modification I could add hydraulic accessories if I wanted to, right?

 

Or this?  "OEM Toro COMPLETE HYDRO TRANSMISSION 108368 108369 fit Work Horse D1-184801 1848"  "Fits Wheel Horse C-81 C-85 C-105 C-125 C-145 C-165 C-175 310-8 312-8 314-8 314-A 416-8 417-A GT-1142 GT-1100 GT-1642 GT-1600 GT-1848 GT-1800"    If I drive about 2 hours from here I could pick up this for about $250.

Edited February 21, 2022 by davem1111

[Dylan2342 11]

Ok, sadly I didn't do well enough when rebuilding the pump. Upon tearing down again, the carrier was seized to the input shaft. disassembly destroyed the carrier. I don't know if I should have used engine builder grease on everything just to give it some time to prime or what. I decided to buy an ebay 1100 that should be shipped to me this weekend. its used and is a total of $250 shipped with free returns. I thought that was a good deal. To buy a new carrier from jacks small engines would have cost like $130. I'm still inexperienced with these things, sadly. expensive lessons lol. I will have to see how well this all goes when it comes in and I reassemble. I'll keep you posted!

[Dylan2342 11]

7 hours ago, davem1111 said:

To the OP here, it sounds like trying to find a used axle/hub would be a good route to take, and if you've ended up with an "extra" Eaton 700 pump I may be interested in buying it. 

You are around 6 hours from me. If you would like to make a trip, then you can take this 700 for $150. that would help me with some costs and I think that should be a good deal for you.

[davem1111 2,027]

4 hours ago, Dylan2342 said:

You are around 6 hours from me. If you would like to make a trip, then you can take this 700 for $150. that would help me with some costs and I think that should be a good deal for you.

 

Sorry your rebuild didn't go well.  I do a lot of things but I have resisted the urge to attempt that with my 700.

 

You're right, I looked up your location after that thought came to me. But I don't see myself making a special trip for that, at least no time soon. However, I do travel to Eastern PA across I-70 at least several times a year to visit family, so maybe an opportunity to swing by might come up. Just made the trip back a few weeks ago so it will probably be a while before the next.  Would you be willing to look into how much it would cost to ship it to me? I'm thinking it would be worth at least another $50 to me to go that route.  And I'm not in a big hurry, since I also have the 416-8 and the grass isn't growing yet. 

 

FYI, that Toro 1100 transaxle I posted about above is near Fort Wayne, IN, and the guy said if I picked it up he'd let me have it for $250. But I'm concerned that even if it bolts to my frame, it looks like the filter would hit the gas tank. So that would require more mods that I may not want to mess with.  Another option I have is this 312-A hydro:  https://www.ebay.com/itm/114897414443   Not sure if you know the history of the one you have and if it was pulled "working", assuming yes. I'd rather help you out than buy that one.  Thanks!

 

Anyone know if a gas tank mod is required to use an Eaton 1100 on a 312-A or other tractor that's stock with an Eaton 700?

[Handy Don 12,088]

34 minutes ago, davem1111 said:

how much it would cost to ship it to

I shipped a 700 to another member last year. UPS $35. Packed in plastic bags and foamed it into place in a box with low-expansion window sealant.

 

Not an expert, but it seems unlikely there would be two different gas tanks or seat support brackets for 3, 4, and 500 series that depended on the transmission.

What is certain is that the 1100's oil filter needs a mounting bracket that won't be there on the 700 or manual transmission tractors. There will be some motion control linkage re-alignment involved. There will be new hydro plumbing since all the 1100's (except, maybe, the Work Horse line?) had hydraulic lift. That plumbing was originally hoses but in later models it was ⅜" steel tubing with a mix of NPT and AN 6 JIC connectors.

 

If there won't be a hydro lift in your install, then you'll need: a) a shunt line from the charge pump, to the filter, b) from the filter into the transaxle, and c) from the transaxle into the charge pump intake. B and C are factory install--you want to be sure to get them if buying a used transaxle--but A will be something you'll need to fabricate.

If there is going to be a lift, it's a LOT of parts and work to switch over from the manual to hydro--including changing the mid-tractor rock shaft.

 

Ultimately, IMHO, for the 312-A your path of least resistance and labor is a replacement or overhauled 700 pump/motor or, failing that, switching over to an 8-speed.

 

Edited February 22, 2022 by Handy Don

[davem1111 2,027]

9 hours ago, Handy Don said:

I shipped a 700 to another member last year. UPS $35. Packed in plastic bags and foamed it into place in a box with low-expansion window sealant.

 

Not an expert, but it seems unlikely there would be two different gas tanks or seat support brackets for 3, 4, and 500 series that depended on the transmission.

What is certain is that the 1100's oil filter needs a mounting bracket that won't be there on the 700 or manual transmission tractors. There will be some motion control linkage re-alignment involved. There will be new hydro plumbing since all the 1100's (except, maybe, the Work Horse line?) had hydraulic lift. That plumbing was originally hoses but in later models it was ⅜" steel tubing with a mix of NPT and AN 6 JIC connectors.

 

If there won't be a hydro lift in your install, then you'll need: a) a shunt line from the charge pump, to the filter, b) from the filter into the transaxle, and c) from the transaxle into the charge pump intake. B and C are factory install--you want to be sure to get them if buying a used transaxle--but A will be something you'll need to fabricate.

If there is going to be a lift, it's a LOT of parts and work to switch over from the manual to hydro--including changing the mid-tractor rock shaft.

 

Ultimately, IMHO, for the 312-A your path of least resistance and labor is a replacement or overhauled 700 pump/motor or, failing that, switching over to an 8-speed.

 

 

Thanks, Handy Don.  Without examining the shop manuals for the 2 models in detail, just looking at the layout of the gas tank and hydro on the 312-A, I suspected what you said would be the case. That wouldn't all scare me off if I had both the proper tools/materials and time to do those mods, but I would rather spend my time and money restoring at least one of these tractors to a much more attractive and stock condition.  I thought about converting the 312-A to an 8-speed but since I already have the 416-8, I wanted to keep the 312-A as a hydro, so replacing the 700 pump sounds like my best approach.

 

Dylan2342, I'll pay you $200 for the 700 including shipping. If for some reason the packing & shipping is more expensive or more trouble than justified by that price, we can discuss. And again, I'm not in a hurry. (Maybe you can use the box & packing from the 1100 when you get it, to ship the 700.)  I didn't mean to "hijack" your thread, but at least you found a potential buyer for the 700. I hope your "new" 1100 works out and you get her rolling soon.

 

[Handy Don 12,088]

3 hours ago, davem1111 said:

...if I had both the proper tools/materials and time to do those mods...

Ah, exactly!

You may want to check with our vendors (A-Z in particular) to see if one of them can rustle up a 700. There's also some parts vendors on FB and CL (near Philadelphia PA).

 

I will warn you that while you can do the swap without removing the transaxle from the tractor, a couple of the bolts are really awkward to get at (you'll want to remove the left rear tire to simplify access). Not an especially hard or tricky job, just not one for someone lacking patience .

 

Personally, I'd want the replacement to be super clean before installing it. Also, a good idea to look at the Eaton rebuild manual to see the steps for flush/refill of the oil. Realistically, this can only be done before mounting it on the tractor.

 

GOOD LUCK! 

Edited February 22, 2022 by Handy Don