TuffTorq K46 Repair Guide with Pictures

[Molerj]

Sounds like the input shaft is the problem. The pulley and the shaft are splined. In some cases the pulley is worse than the shaft, but through experience, replacing the pulley will probably result in having to replace the shaft and pulley at a later date. You may be able to replace the shaft without splitting the transmission. Time to pull it out & find out how things look. Then a call to Tuff Torq.

 

[wactbn]

My oil-change-only method with 5W50 synthetic didn't work very well. I did a half season of snowblowing on my L130 (370 hours) with the new oil. We had a light snow season here in NH. It would drive OK when it was well below freezing, but when I ran it during the last early spring snowstorm, I had trouble reversing up a shallow driveway after snowblowing for 30 minutes with the snowblower attachment and 50 lbs of ballast. The K46AC would whine all the time regardless of the temperature.

So I finally took the K46AC out last weekend and took some "before" photos.


The parts were well scored and look as bad as the pictures posted earlier by sjsmith and idakiteman:
http://www.tractorbynet.com/forums/parts-repairs/164892-tufftorq-k46-repair-guide-pictures-43.html#post3083331
http://www.tractorbynet.com/forums/parts-repairs/164892-tufftorq-k46-repair-guide-pictures-45.html#post3112087

After much self debate on sending them to a machine shop or DIY, I decided to try the cheapest method possible and sand them myself. Instead of paying $40+ for a granite surface plate or machining a 2" steel disc, I used a scrap piece of 3/8" thick porcelain floor tile and 400-grit wet/dry sandpaper.

I noticed that the pump case faces were simply fly cut (typically 0.001" tolerance), so I'm sure my ghetto porcelain tile method would produce as good or better surfaces than the factory finish. I'll even forgo the 600-grit sanding and see if I can get away with just 400-grit.

Results were very encouraging, as my repairs ended up looking a lot like the "after" pictures from above.


Note that the bottom right photo is of a half-sanded part, where the deeper grooves are still very noticeable. Each part took about 30 minutes of constant circular, oval, and figure-8 motion under a steady trickle of tap water to sand down until all score lines and nicks were gone. I probably could have made the process go a bit faster by using new pieces for the initial material removal.

The 5W50 oil looked pristine, so I'll just reuse it when I reassemble the K46AC this weekend. Many thanks to Joebob, idakiteman, and sjsmith for the inspiration and saving me $$$ in replacement parts.

 

[cchc28]

Sounds like the input shaft is the problem. The pulley and the shaft are splined. In some cases the pulley is worse than the shaft, but through experience, replacing the pulley will probably result in having to replace the shaft and pulley at a later date. You may be able to replace the shaft without splitting the transmission. Time to pull it out & find out how things look. Then a call to Tuff Torq.

So, pulled the trans (which was so easy). Found that the pulley splines were stripped. The input shaft splines look great, after a little filling.

Question, is the pulley a Tuff Torq part or John Deere?

 

[Molerj]

Call tuff Torq, In some cases, it is a JD item, others not. I found the difference in price to $30.00.

So, pulled the trans (which was so easy). Found that the pulley splines were stripped. The input shaft splines look great, after a little filling.

Question, is the pulley a Tuff Torq part or John Deere?

 

[wactbn]

So, pulled the trans (which was so easy). Found that the pulley splines were stripped. The input shaft splines look great, after a little filling.

Question, is the pulley a Tuff Torq part or John Deere?

I looked up your K46C at the Tuff Torq parts website. The pulley is a Tuff Torq part number 1A646025750, same as the one on my K46AC. You may need to call Tuff Torq or register at the website to buy online.

 

[Molerj]

That part costs 10.30 but there is a minimum order of 25.00. As I stated earlier, buy the shaft also, you will find that if you don't, that pulley will end up getting stripped out also. I replaced just the pulley on a customers and it lasted a little over a year, which was probably more like 5 months actual usage.

 

[wactbn]

BTW, here is a photo of the two drain bolt locations as suggested by Tuff Torq, using their drain bolts.


Note that they are not at the lowest locations in the pan. Therefore you will need to invert the transaxle and drain the oil through the upper vent cap in order to do a complete drain.

 

[nitusoxide]

I am hoping for some advice from people who have rebuilt there tuff torq transmission. That time has come for me and like most people I am trying to decide on how much to invest in this old mower. I have a Scott's (john deer) 20-hp mower. The transmission is tuff torqs k51E. I know it is a little different than the model, but this is the closest online form I could find. I called tuff torq today and they told me to buy the rebuild kit $320.00. I asked about cheaper options Derick said to get the pump block kit $58, the cylinder block kit $71, filter $8 , sealant $13, and center case A $88.total $240. My question is do I really need center case A. what is it can I just clean up the old one, is it a good investment? The mower is in good shape the engine is strong. the transmission just go to weak. I think the mower could last another 10 years but like any big investment in an old item, I still worry about other problems and just end up throwing it away. Any feed back and pointers would be much appreciated.

 

[RBLapham]

If it were me I'd follow Derrick's advice - he really knows what he is doing. You could sand down the case and hope it works, but for $320 over 10 years - $32 a year or $.62 a week go for the kit.

 

[wactbn]

I called tuff torq today and they told me to buy the rebuild kit $320.00. I asked about cheaper options Derick said to get the pump block kit $58, the cylinder block kit $71, filter $8 , sealant $13, and center case A $88.total $240. My question is do I really need center case A. what is it can I just clean up the old one, is it a good investment? The mower is in good shape the engine is strong. the transmission just go to weak. I think the mower could last another 10 years but like any big investment in an old item, I still worry about other problems and just end up throwing it away. Any feed back and pointers would be much appreciated.

Like you, I started out planning on buying a similar parts kit from Derrick, but it was going to be close to $300 with shipping. Since I only paid $750 for my used L130 (with the busted K46) last summer, I simply couldn't justify that repair cost. I ended up buying just the fan, filter, vent & cap, oil drain bolts from Tuff Torq ($28 in parts + $16 S&H!) and bought the sealant and Castrol 5W50 synthetic from the local auto parts store. In hindsight, the oil drain bolts were a total waste of time and money since the best way to drain is to remove the K46 from the mower and turn it upside down anyhow.

If you have a few hours and elbow grease to spare, just re-sand the revolvers and center case by hand. Or take them to a machine shop. It will be much cheaper than buying new ones. I would still recommend buying a new filter, cap & vent from Tuff Torq. It's up to you to weigh time vs. money.