TuffTorq K46 Repair Guide with Pictures

[teQuest]

My L130 with a k46 just smoked a drive belt. I got the belt off and was making sure all the pulleys turned freely before reinstall. The K46 pulley/fan don't seem to turn real freely. Is an amount of resistance normal? I'm not sure if I need to rebuild or just put the drive belt back on. Or maybe just pull/clean/install new filter and fluid. I looked at tuff torq and didn't see where they listed
1. Cylinder block (pump) kit
2. Cylinder block (Motor) Kit

I called derrick and inquired about above and he just steered me to the rebuild kit. At over $400 with fuild, i'm not sure it's worth it.

I have just finished watching & reading 100 stories about Tuff Torq & was thinking maybe these things are crap. The wife gave me approval for a new mower & thought **** I will just check a few things first, and wonder if the guys that did "clean rebuilds" did not check these things first. #1 a bent neutral "roll it" rod could be bent, #2 the drive belt could be toast (mine after 9 years of TX heat looked like glued sawdust). #3 my engage/brake off swivel plate that holds the tension pulleys seemed to be binding. (I bent a 1/4 extension trying to break the nut holding that plate on so just oiled & worked it loose.) #4 weak JD 30 weight oil, replaced to 5w/50 synthetic.

Without all of the information would not have pulled my 40j/202/k46, that was dragging but just slow at start up & later gained speed. The plan was to check to top magnet which was cleanish & if so just changed oil for the first time in 9 years & replace the belts. My yard is about 3 acres & often cut the riding arena & entry so do about 6 acres 12 times a year, with the yard more so so the bugger gets used. Anyway the oil change & belt change fixed my old LA110 that almost wants to squeal rubber now. With the mower off & the K46 TT out the drive belt was not too hard. I was able to snake the drive belt around without pulling the front mower pulley as some instructions state. Used a construction pry bar to lower the plastic tension pulleys for the drive belt. I put the new belt around the transaxle before lifting it into place.

When researching new lawn tractors it seems 90% have a k46 transmission even the ones in the $4 to $6K range, & same motors no matter the paint color , so this country boy will just keep welding the deck & replacing spindles every few years. Anyway felt obligated to post this alt option after seeing so many post & hope these check points might save someone a buck.

 

[John Deere L130 Derek]

Hello, Tractor By Net. First time posting on here but I've been reading most of these posts about Tuff Torq K46 AC transaxles.

Now I've got an issue and need some help troubleshooting.

After almost 500 hours and 12 years on a JD L130 with a Tuff Torq K46 AC transaxle it started to groan and loose power. So, last winter I pulled it expecting to find some normal wear and tear and requiring a rebuild kit.

So, I bought the rebuild kit and a new set of differential gears. I installed the new pump, motor and center case with IDS filter kit. I also replaced the pump thrust bearing/swash plate with the upgraded kit. The most obvious parts that needed to be replaced were the differential gears as they were collecting on the magnets. As also recommended I have replaced the oil with Castrol syn 5w-50.

Now I have it on the bench and running the pump with a drill and can't seem to get any power out of it. After bleeding the air out of it the axles will barely move and I doubt they would with wheels attached. I can see the air escape through the oil fill cap so I'm fairly confident that it should be good to go.

I did talk to Tuff Torq yesterday and they said it could be debris from manufacturing in the new center case. I personally find that a little hard to believe but was wondering if anyone else has experienced that.

Between all the parts I mentioned above and a new set of front wheel spindles and bearings I'm in this thing for over $600 and it hasn't cut a blade of grass yet this year. I was hoping to get another 12 years out of it but am considering taking it to the dump if something doesn't change!

I feel I'm fairly competent and have put this thing back together correctly. I work on 7000 horsepower marine diesel engines for a living but this is kicking my butt. Any help would be appreciated.

Thanks.

 

[RBLapham]

If bench testing using a drill, it will barley move as the drill is way slower than the motor in the tractor. If you feel confident you did everything right I'd say put it back on and try it - it is probably OK

 

[John Deere L130 Derek]

Yeah, I thought that also. So I had previously installed it and ran it through the air bleed procedure but still got nothing. I've since removed it and verified I put it back together correctly and that's why it's on the bench. I might try reinstalling it tonight but I'm not hopeful that I'll get different results since I haven't done anything different. Thanks for your quick reply.

 

[RBLapham]

Biggest causes of not moving after a rebuild are 1. the TicTac pin has fallen out - it works with the "Free Wheeling" rod and linkage. 2. The "Free Wheeling" rod not pushed in. 3. Square Key way pins are not on wheels between the wheels and axles. See post #4 and #14 about the small rod -"Tic Tac"
Also were you sure you filled it all the way up? Right near the top of the fill hole it splits into two compartments - you must fill above that point. It should have taken a full 2 quarts- if a lot less you need more.

 

[John Deere L130 Derek]

Yeah, so...

Put it back in. Still nothing. The unit goes in both directions with no issue. I checked the tick tack pin and washer when it was on the bench and found them to be installed correctly. When the 'free wheeling' rod is pulled out during axle movement it quickly stops axle rotation. Same when it's pushed back in. Will easily go in both directions just with no power. I.E. I can stop the axles with two fingers. I put a full 2+ quarts in of the Castrol Syn 5w-50 so I don't believe that's the issue. The wheels aren't on so the keyways are not an issue.

I should've also mentioned that I replaced the drive belt with a new one so I don't believe there's any slippage or stretching going on there.

I had better performance from my old motor, pump and center case but the machine was having trouble getting up the inclines. I don't know if the gear replacement would've corrected that alone but I'm considering putting back in the old pump, motor and center case and seeing what happens.

Additional thoughts?

 

[RBLapham]

Your judging the power without putting it on the ground with wheels on? Try it fully back together.
Another thing that helped a few was to purge the unit with it on the ground with wheels on - rapidly shift from forward to reverse several (bunch) times and that has fixed it.

 

[John Deere L130 Derek]

I'm going to put it back together tonight and try it again tomorrow morning. It doesn't make sense that it matters if it's on the ground or not, has the wheels on or not. That axle doesn't have enough power coming out of it to rotate with the wheel on it. It'll take less force to stop the axle with the wheel on it also (think of the mechanical advantage you have when you're on a breaker bar versus a small wrench). I can purge the unit as you suggest with it on jack stands and have done it multiple times over the course of days to no avail.

The good news is that I'm becoming so efficient at installing/removing this transaxle that it only takes me 20 minutes or so to have it wide open and drained ready for another troubleshooting idea.

After some additional thought, I'm reconsidering putting back in the old pump, motor and center case. I tried that after I got the differential gears replaced and it only worked for ~20 minutes or so before it overheated and died all together. So I don't there's much value in trying that idea out.

 

[teQuest]

I'm going to put it back together tonight and try it again tomorrow morning. It doesn't make sense that it matters if it's on the ground or not, has the wheels on or not. That axle doesn't have enough power coming out of it to rotate with the wheel on it. It'll take less force to stop the axle with the wheel on it also (think of the mechanical advantage you have when you're on a breaker bar versus a small wrench). I can purge the unit as you suggest with it on jack stands and have done it multiple times over the course of days to no avail.

The good news is that I'm becoming so efficient at installing/removing this transaxle that it only takes me 20 minutes or so to have it wide open and drained ready for another troubleshooting idea.

After some additional thought, I'm reconsidering putting back in the old pump, motor and center case. I tried that after I got the differential gears replaced and it only worked for ~20 minutes or so before it overheated and died all together. So I don't there's much value in trying that idea out.

I purged mine with the wheels off & just grabbed the rotating axle to make sure both would turn in F & Reverse. I was a ship's engineer 40 years ago, but it seems big stuff is easier. One wonders if the brake is released on the unit, or does it release with removal? Well no expert on this but often the solution is simpler than originally thought.

 

[John Deere L130 Derek]

Well, contacted the distributor who sold me the rebuild kit and am now awaiting all the return authorization paperwork. Tuff Torq or the distributor is going to test it to see if the parts (pump, motor, center case) are defective and then choose a path to go.

Looks like it'll be several more weeks before this machine is up and running.