TuffTorq K46 Repair Guide with Pictures

[L120]

Problem is the fill port, it is right under the fan and also not easy to remove. Something might be done to rig a fill tube or there are some K46's that have a reservoir tank. But it is easy to remove and turn over to drain so not worth the mod or drain plugs, for every 3 years or so.

Oh crap...you're right about the fill hole location. I betcha someone can rig up something which is just the thing. I'm OCD about not "rigg'n" stuff always to do a proper job. Hey, maybe the drain plugs can be magnetized to help clear the metal out when draining?

 

[L120]

Dropped the K46 today and got er drained. The fluid looked almost new. No metal on the magnet. How is this possible? Was looking forward to cracking that case open and order some parts ! lol

Anyway...this may buy some time to investigate the heavier K56 pump & motor parts to be used in the K46 tranny. Truthfully, I had my heart set on the K66 upgrade kit, but the price of $1800 scared me away.

 

[Dapped]

I really recommend reading my posts #847 and #848.
Still working good to this day.
Don

 

[L120]

Parts Required to Convert K46 to K57 This lists out as a K57A (Simplicity spec'd) hydrostat...This was the current pricing also....It's not cheap, but you have alternatives...

Item #/ Part Number on diagram / Quantity / Part Number Description/ Cost
1. 1 1 1A646088840 Pump Shaft (K57A) 25.47
2. 100 1 187Q0026010 Charge Pump Case Kit 8.35
3. 102 1 1A646088350 Inner Rotor 4.61
4. 101 1 1A646088360 Outer Rotor 4.82
5. 103 2 22351030018 Roll Pin 3.0 x 18 0.21 @
6. 97 1 1A646088450 Charge Spring 2.68
7. 96 1 1A646088410 Pin 2.5 x 9.8 0.34
8. 83 2 1A646025300 Spline Collar 1.34 @
9. 26 1 1A646088211 Filter 8.64
10. 87 1 19215489090 Snap Ring 0.26
11. 37 1 187K0099750 Motor Thrust Bearing 28.08
12. 201 1 1A646099530 K57R Repair Kit 373.81
13. 47 1 1A646029010 Magnet Holder 1.83
14. 8 2 19216324360 Magnet 2.94 @
15. 2 1115 1 liter 5w50 Synthetic Motor Oil 8.29 @
16. optional (104) 1 1A646099630 Thrust Bearing/Swash Plate Kit 37.12
Total $484.45 plus shipping

This is amazing. Thanks for the list of parts. I'm researching all options for repairing my K46 when it goes kaPOOT. One thing I have noticed is that the rebuild kits are almost the cost of a brand new transaxle. For $150 bucks more, why wouldn't someone simply get the whole thing brand new bearings, gears, seals, shafts & everything.

Then there is the guy selling the K66 upgrade kit online for $1,900. That's the price of 3-K46's. Not that the guy is making huge profits as a new K66 costs $1,200 new then all his parts to make it work. I guess it's worth it, but not sure if my tractor use would require the kit. Already bolted in a new 27hp Comercial B&S engine and even the cost of the K66 upgrade along with the price I paid for the used JD L120 STILL is cheaper than buying a brand new tractor with the same specs I've built mine for so far.

Really all many of us need is something reliable to mow grass and occasional small trailer haul to move dirt or fallen limbs to the burn pile. OH...some of you plow & blow snow. I guess that would take a toll on a stock K46 transaxle.

 

[L120]

Update:

I have been running this oil for a month now and have about 15 hours accumulated.
It is working as good as it did when I first started using it.

Here's Two example of the differences between 5 Winter 50 synthetic and the Volvo Penta 75 Winter 90 synthetic.

#1

Before: Pull up to wall, stop and go full speed ahead; nothing other than transaxle noise with very little forward power pushing.

After: Pull up to wall, stop and go full speed ahead; tires took turns spinning out.


#2

Before: Back up to 4" raised concrete deck, stop and then continue full speed in reverse; nothing other than transaxle noise with very little pulling power in reverse.

After: Back up to 4" raised concrete deck, stop and then continue full speed in reverse; lawn tractor climbs up the 4" deck with ease.

There is no degrading power after 1 hour of use.

I hope this may help some of you, it is a real cheap option vs pump, motor and center case replacement.
Note: I previously had done the pump. motor and center casing sanding and lapping. This did help back then however it was still not full power. I think when one gets as far as doing that there is also wear in each piston and casings which does not get addressed. This thicker oil helps to address this issue.

Don

Thanks Don. Yanked my K46 out yesterday and let er drain all night. The fluid was clear if you'll believe it and the magnet was clean. My L120 was MFG'd in 2005 and I bought it used in 2016 with 330 hours on it. Something tells me the tranny in the used Deere has been replaced before I bought it. I've mowed all season and noticed the white fan on top of the tranny all the fan blades were sheared off. That must have happened this spring when a stick got up in there so I've mowed all summer in hot Texas with no air cooling to the K46.

I'm with you on the heavier oil that could help produce more hydraulic pressure. Maybe something as you stated visc & weight that isn't too heavy or too thin.

 

[Neo]

This is a very long thread but thanks to all the contributors I managed to pull of what I previously thought was an impossible job :laughing:

Fo some time I've been worried about my K46 dying on me. 5 year ago I bought a John Deere L120 cheap because the Trany was leaking and it had hardly any drive. I replaced the wheel shaft seals and change the oil and all came good but I thought it would go bad eventually so 4 years ago I picked up K46 off of eBay (mega cheap!) which looked similar at the time. Well last week the tranny moans and groans started so I knew it was time to pull out the K46 in storage and swap the two K46's over. Well after close inspection (and a test on the mower) it became clear the newer Trany was quite different the old one ...

• Wheel Shafts were much shorter ... norrower wheelbase causing one of the tyers to rub under the wheel arch.
• Driveshaft was an 1" shorter .... Meaning the drive belt would be out of alignment.
• And by far the worst .... Forward pedal went backward and back peddle went forwards .... which could be fun on a dull day :laughing:

So long story short I opened up both transaxles, swapped the wheel shafts, rotated the wedge block but was unable to remove the driveshaft without destroying the seal (and possibly bearing) onto the newer trany.... She's all up and running now ... Drive belt is still out of alignment but it seems happy like that :thumbsup: ... fingers crossed :laughing:

 

[stevem5215]

Well, thanks to this thread I have successfully repaired my Craftsman Pro 24hp 42" model with the K46BT tranny. It was slow (and whiny) in going up hills and finally got worse last week. The tractor has been in service for 2 1/2 years and has 220hrs on it and was used pretty heavily on 4 acres during that time. I pulled the tranny out and popped off the rubber cap. Didn't have many metal shavings on the magnet. Dumped the dirty looking oil into a measured bucket to ensure I got all 2.15 quarts out of it. Then I poured in my 5W-50 syn that I bought at Advance Auto parts. ($9 a quart) Cleaned the magnet and put it back together with a new drive belt (1/2" x 92.4" - 130969) and purged it with out having the wheels on the ground moving the drive back and forth till it was smooth. Tested it out on my hills here for an hour cutting the grass and all is good again ! Thanks to all who have posted with the fixes. It's worked again !

Steve (Pittsburgh, Pa)

*** This is an update on my serviced K46 back in 2012 ***
As of 5/19 this tractor tranny is still working the same as the day I pulled it and did the oil change and belt r/r. I don't know the hours anymore as the meter quit working but it has been almost 7 years later! So who's to say a K46 with proper routine maint can't last the test of time. This is over 10years old now. How long do we expect things to last ? Forever ? 20 years ? I could be dead by the time it quits!

Steve

 

[buckeyefarmer]

Re: TuffTorq K46 / John Deere L110 Transmission Repair Guide with Pictures

My k46 making lots of squeeling noise, wont go up a hill. New fluid last yr. Its 12 years old.

 

[Thewoj]

I tried changing fluid a few weeks ago on my Husqvarna YTH24V48 (fast tractor) with roughly 700 hrs on it. Didn’t make a difference other than it went a little faster in reverse than forward. I broke down and purchased the entire kit from Tuff Torq (2019 prices about $450 plus tax and shipping). Rebuild took all of an hour after reading all 96 pages. The mower moved but still didn’t go like before when it was new so after a few weeks I checked fluid level and it was fine. Somewhere in on of these pages I read about adjusting the control arm by giving it a little more bend. Did that (breaking my bench vise in the process I might add) and bam! It moves like it was brand new again. I found the control arm was getting stopped by a portion of the frame preventing it from moving all the way forward. Hopefully I can get another 9 years out of it.....now off to the steering mechanism which is an absolute horrible piece of engineering. Thanks for the rebuild advice! Mine was stamped as a K46 but was actually a K57R.

 

[Flyboy712]

Hey,

First post here on the site, but what brought me here was this thread. Great info and a big help! Thank you.

My story is a bit different but the same and I wanted to share it and give TuffTorq a kuddos.

I bought a brand new Husqvarna YTH24V48 at the end of June last summer to mow my 2.5 acre yard. At about 6hrs on the machine reverse went out and would only move very slow and only on a hard level surface. At 9hrs forward did the same thing. It was past my 30day return to Lowe's so I couldn't bring it back and so I began the process of trying to get in touch with Husqvarna for warranty work. No such luck. I got nowhere with them not even a single reply or call back. I then started searching out service centers to see if I could make any progress there. All of the service centers on husqvarna's website within 150mi of me all stated they don't work on riding mowers.

I thought well I'll drain the factory oil and put in a 50w synthetic and see if that helps. It did a little, I was able to roll on level grass but not much more than that. By now we were into fall and getting ready for winter so it became something that was on the back burner for a bit.

After the first of the year I attempted the Husqvarna support thing again with the same results of nothing. I figured I was out of luck for getting any warranty work done and decided to get ahold of TuffTorq and see if I could order some parts or a new transmission.

I got a very nice lady named Kristen on the phone and explained my situation and I said I wanted to order some parts for it. She said before we do that let me find one of our service centers and we'll pay for the repairs. I thought cool! Unfortunately no service centers within 150mi and the closest one said they wouldn't work on it.

I got back in touch withTuffTorq (nice guy named Gill this time) and told him what the shop said and I asked if I could send it to them for repair. He said no but if you take a picture of your hour meter and email it and your address we'll send you a new transmission.

Less than a week later I had in my hands a brand new transmission free of charge!

Great customer service and thanks for not letting me buy parts or a new transmission.

They didn't want the old one back so I think I'm gonna open it up and see what's happening on the inside that caused it fail so quickly. If it's salvageable I think I'll machine the pump block and pump and motor ends and clean them up and have a spare if the new one quits working.