TuffTorq K46 Repair Guide with Pictures

[trainguy]

Got my LT-190 up and running, here is what I did. I took the transaxle out and found the pulley spline was all wore our and the pulley was rotating freely on the shaft. I changed the oil to Castrol 5W50 and removed the magnet plug, cleaned some small filings from the magnet, reinstalled it as recommended by a few members, installed a new pulley along with a thin washer under the retaining clip to ensure the pulley does not have any upward movement like it did previously, nice and snug now. Everything works fine. Hopefully it will last a little longer. thanks to all who replied

[RBLapham]

Derrick said the "charge pump" designs start w/ the K57 and above.

Derrick also has parts to add the charge pump to the K46 to make it a K57, it is in one of the posts in this thread someplace (back about page 14). I would defiantly add those parts if I rebuild mine. Also thanks for the thoughts on the oil and contacts.

[RBLapham]

Did a better search of this thread - the K57 upgrade kit is discussed in post # 104 on page 11

[idakiteman]

RBLapham...thanks for pinpointing K57 upgrade post. Will take a good look. Also, for clarifying the the gray sandpaper is wet/dry. Next time I'd try grinding w/ water as lube instead of machining oil....it'd make the cleaning process a lot less hassle, and as sluff fills the paper when grinding, just dipping the puck in water and brushing may flush lots of the sluff, keeping the paper more effective and reducing change-outs. Thanks.

[Kyle_in_Tex]

Thanks for posting a comprehensive post to lap the faces on the worn parts. This thread combined with Derrick at TT is saving a bunch of people a bunch of money.

To Trainguy,
you have one of the highest houred trannys I've heard about. Gives the rest of us some hope! I would still recommend the synthetic oil over the standard Castrol. It takes the summer heat better.

[idakiteman]

Did a little homework about likely effects of oil differences. There appear to be two advantages to synthetic 5W50 over an ordinary 10W30. First, as I speculated earlier, the temperture at which the oil begins burning and forming carbon abrasives is about 50 deg. F higher in, for example, Castrol Syntec 5W50 compared to ordinary 10W30 from Chevron, Pennzoil, Valvoline, Quaker State, etc. See table at bottom of this page: More Than You Ever Wanted to Know About Motor Oil. Of course, there are metallic particulate abrasives at work too, aside from just carbon.

Second, and maybe more important, 5W50 gets "thicker" at higher temperatures vs. 10W30. When overheated, a 30 weight oil gets a lot thinner than a 50 weight. The thicker oil will maintain a thicker film separating "contacting" parts. So, microscopic abrasives of diameters that match or slightly exceed 30 weight oil film thickness (thus grinding opposing surfaces) might stay in suspension in a thicker 50W film and reduce grinding.

[trainguy]

Got my LT-190 up and running, here is what I did. I took the transaxle out and found the pulley spline was all wore our and the pulley was rotating freely on the shaft. I changed the oil to Castrol 5W50 and removed the magnet plug, cleaned some small filings from the magnet, reinstalled it as recommended by a few members, installed a new pulley along with a thin washer under the retaining clip to ensure the pulley does not have any upward movement like it did previously, nice and snug now. Everything works fine. Hopefully it will last a little longer. thanks to all who replied

Well that repair didnt last very long, plowed about 200 feety of laneway, went to put it in reverse and the belt came off, cant get the belt to stay on the pulley, now I feel some obstruction in the pulley,guess the transaxle is finished now. I'll have to call TuffTorq for a whole new transaxle.

[sjsmith2262]

Well that repair didnt last very long, plowed about 200 feety of laneway, went to put it in reverse and the belt came off, cant get the belt to stay on the pulley, now I feel some obstruction in the pulley,guess the transaxle is finished now. I'll have to call TuffTorq for a whole new transaxle.

Trainguy,
I'm sorry to hear that your repair didn't last very long!

We live in Wisconsin and we've had quite a bit of snow lately. Since repairing my K62 transaxle, I've put on a little better than 9-hours of hard snow blowing. My repaired transaxle has held up great. I don't see any problematic symptoms, such as moaning and/or slowing down. :-) For what it's worth, my Scotts 2048 has about 1,150 hours and she continues to plug away...

If it were me, I try to machine (sand down) your motor pump and case assembly, you should be GTG. That being said, I would recommend replacing the oil filter(s), my K62 had two of them and they cost about $30 total.

Good luck & Merry Christmas!

[idakiteman]

Well that repair didnt last very long, plowed about 200 feety of laneway, went to put it in reverse and the belt came off, cant get the belt to stay on the pulley, now I feel some obstruction in the pulley,guess the transaxle is finished now. I'll have to call TuffTorq for a whole new transaxle.

Trainguy...since you bought the LT190 used...is there any chance the prior owner attempted tranny R&R and got the reassembly wrong?...maybe reversing position of pulley and fan on the drive shaft? Or maybe, since 900+ hours on the machine, it's not the original transaxle and was replaced just before sale with something that isn't the right configuration for your tractor? Look at Tuff Torq website and find exploded diagram for your model tranny and see what it shows for fan/pulley position.

[joebob]

Great post, Ida. I had the stuff ground for $25, cuz I was lucky enough to find a shop that would do a "side job". The owners father hung around working in the shop doing just such things. Thats what you need to watch for. You're rite, $70/ hr. surely would'nt be worth it.
Cheers
Joebob