TuffTorq K46 Repair Guide with Pictures

[russky]

LotsofGreenGrass,
Many many thanks for your blog, I have just bought a 2nd hand l110(4 months ago) and as is my usual luck, it stopped moving, but thanks to your brilliant article, it is now running like a new one.
Couple of things I discovered are,
1- when re-assembling the gear box its a good idea to leave out the 2 little brake shoes, because if you don't get the brake disk perfectly lined up when tightening the motor housing down, it will break the disk(swearing and $15 more! ).
2- If you have a picture of where the little grain of rice valve thing comes from that will help future readers to find its home.
Thank you so much for taking the time to do this post, I will be forever grateful.

 

[wactbn]

I see what's going on. Instead of clicking parts, click the blue serial number that matches your's. Then you get a screen like attachment number 2 where you can cherry pick pieces!:thumbsup:

View attachment 388815View attachment 388816[/QUOTE]

Thanks for the workaround! I didn't think of looking there. I'm going to test another theory for my short life after rebuild - I'm going to sand down my pump, motor & case, clean out the filter, and replace only the gears that are showing bad wear, and see how long that fix lasts. I'll be thrilled to get 100 hours out of it.

 

[wactbn]

In my mind, the key to the operation is the fact those pump and motor blocks were worn more in the middle than on the outer edge. Sand them puppies down a lot or the job isn't going to go tight for you. At least that's my new personal theory on it. That idea may be old and all over this thread, so I just want to couch my "findings" as quite possibly being found already a long time ago by a whole bunch of people. If they weren't... I hope it helps out now and from here forward.

I'm back in business for now, have my eye on a new X530, just don't know if I'll pull that trigger or not. Does the K72 grenade itself like this after a few hours?

Thanks for reading, -Daron

Hi Daron, I remember seeing your website (especially the blade-less fan!) over a year ago and it helped me with rebuilding mine.

Your finding is a small detail that hasn't been highlighted often in this thread. The most common observations were overall scoring in the pump/motor/case, dirty oil, metal bits in the filters. I sanded mine down until all scoring marks were gone.

There was also a post about the gears, and whether they were powder gears.

These photos from your web page shows wear on your gears too (L: narrow gear in the middle; R: output gear from motor):

Did you notice if the wear was any worse when you took it apart this time?

I don't know about the K72, but someone was still able to wear down his K66 conversion more than once. Nothing lasts forever, but if you got 83 hours from your K46 rebuild, I got 10-25 hours on my K46 rebuild, and someone else got 125-155 hours from his K66 rebuild, this tells me the Tuff Torq design has serious durability issues. All they do is make the parts bigger for the larger units, but shares the same fundamental design with gear & differential parts submerged in the same oil sump as the hydraulic pump parts. Now I'm not so sure JD's decision to use conventional oil is the root cause here, when we still see failures with 5W50 synthetic.

 

[L118]

Hi all, im so glad i found this forum, the detailed info is amazing! I have a JD L118 mower with a tuff torq t40A, (now @ 302 hours) and the requisite issue of slowing to a crawl after 20 minutes of mowing.. so after watching several how-to vids and perusing this thread, i invested in a new motor/pump & seal kit from TT. then decided to go ahead and replace the differential gears while i had the case open. the replacing of those parts went pretty smoothly and i refilled with 5w50 synthetic to within .75" of the oil cap per TT's specs. reattached the tranny, purged for about 10 minutes and then proceeded to mow. The 118 had new life!, it jumped when i went forward & reversed, with better speed than ive experienced since i bought it used last spring. BUT... after about 10-12 minutes the problem returned- slowing to a crawl.. im open to suggestions on what to do with this big green boat anchor sittin' in the back yard. i may have messed up in rebuild, but i (think) i was very thorough. thank s in advance for any suggestions of what to check. maybe there's something else that needs to be replaced? the engine seems to be great, if i can get it moving its a good mower.

 

[Daronspicher]

Did you notice if the wear was any worse when you took it apart this time?

I hadn't gone back to look at these pictures, but now that you bring them to my attention, there was just a bit more wear on the gear which has the brake disk on it than what you see here. The other gears were showing no wear at all still.

I pulled that slightly worn gear out and flipped it end for end and now it's running on a new spot.

These hydrostat mowers are pretty nice compared to grandpas gear driven thing. Even with them failing like they do, they are better than the variable speed belt driven thing that is sometimes on the market. When I"m mowing with a soft hydrostat, I wish I could figure out a good way to mount up a good old gear driven transmission and just put up with all the shifting and nonsense.

would it cost that much for someone to show up on the market with a design that cost $200 per unit less to build, but it out torques the Tuff, out lasts it as well. If the main parts inside were to go bad, $25 +sh and a couple hours work and you're good as new?

I really feel Tuff Torq has gotten lazy about it and can just ride the market while we're all out here spitting mad wishing they'd be taken out by a builder of a better mouse trap. I'd cheer them on if they were the ones who built it.

It's been a lot of years, at least why hasn't someone pulled the plug completely on the K46 and made the minimum the K66 or K72. If the previous post was right, same design, just everything is bigger, then the actual cost to produce wouldn't be more than $100 or $200 per unit. Just a bit more metal in the casting, little heavier to ship, but not $2200 more. Mount K72's to those disposable Home Depot mowers. Is that overkill on the tranny size / strength? Yeah, but it should last dang near 25 years before anyone has trouble pulling a hill.

To say, seems Tuff Torq, John Deere, Cub, Sears, everyone who still puts a K46 out the door is in on a giant scam on the consumer. Consumer has no competition to run to.

-Daron

 

[wactbn]

BUT... after about 10-12 minutes the problem returned- slowing to a crawl.. im open to suggestions on what to do with this big green boat anchor sittin' in the back yard.

I don't envy you - the surest way to find out is to open it up again and see what your brand new pump and motor look like now. I suspect your gears are going to look beat up like mine...

 

[JWHIT]

THANKS TO EVERYONE for all tips my L120 that I got new in 2004 has 229 hrs has been working good but I pulled trans dumped oil smelled alittle burned replace with 15-50 syn works great I think maybe alittle faster hopefully make it last another 230 hrs THANKS AGAIN FOR ALL INFO JIM

 

[JWHIT]

Has anyone ever tried to put a L110 42 inch bagger on a L120 48 inch deck THANKS

 

[JRobyn]

I have been following this thread since I was pretty sure my new to me Cub LTX1050 with 180 hrs had the K46. I was surprised and delighted when I finally spotted the tranny ID plate on it and it is a HydroGear!

- Jay

 

[NDBBM]

Day one of the rebuild. What a "fun" time. I'm reminded why I am a computer whiz and not a mechanic after this endeavor. I have a question. And I'm going to cringe at the answer I'm sure. But here goes. Let's just assume I got everything right inside and back together a-ok. The little lever on the outside that has the brass rod connected to it. The one I pull out to put the machine in neutral to push it around...Will that lever have any sort of function before the case is filled up with oil and bled? I thought I had everything right. Sealed the case. Was getting ready to fill it when I started fiddling with that lever and it was just sort of floppy. I was convinced I screwed something up and yanked it all back apart. But I'll be darned if I know what it is. The little tick tack thing looks to be in the right spot. I dunno.