Mahindra 2555 HST Cab hydrostatic transmission problems

[sdoubledub]

I have a huge problem, and hopefully someone has experienced this, or heard about it. My tractor -
2015 with about 280 hrs, stopped going in reverse. The indicator light in the cab has "F" (forward) showing even though the pedal is in the regular position. In essence, it's overriding itself and assuming both pedals are being touched simultaneously, which makes the tractor not do anything. Has anyone experienced this? I checked under the cab, and both pedals appear to be properly connected to the spring mechanism. There are no loose wires that I see. Both L and R have 3 wires that appear to go into some solenoid of sorts. Both sides appear snug, and again no wires disconnected. This happened in the cold, while blowing / blading snow. Occurred approximately 10 hours after the dealer did the following:
Removed spring from throttle motor to achieve proper rpms,
Installed mid-pto kit and front mount snowblower
Also, the hydrostatic "sensitivity " button on the left appears to be detached (rocker just flops loosely). It's been like that since I got it used at 240 hours, but figured I'd mention it.
Thank you for any light you can shed on the problem,
Scott

 

[sdoubledub]

One more thing, the back of the tractor by the transmission fluid port was warm to the touch- about 100 degrees (96 actually, but that was 5 or 10 minutes after shutting down the tractor in 20 degree weather, and a solid 5 minutes of not using the hydrostatic before that).. not sure if that's normal. What is the normal temp range of that housing, or fluid, under load? Tia

 

[JerryK]

Here is a link to a fellow that had the same problem. http://www.tractorbynet.com/forums/mahindra-owning-operating/375435-reverse-stopped-working.html Boils down to you have to get the F off before the HST controller will let you go in R ...... Possibly you have water/ice in the F switch, if it is not just out of adjustment. The switches send a low voltage signal to the controller, I think it is only a 5 volt system from what I can gather.... I live just 10 miles North of you, West of Vandy ....

PS: If you are working the hydraulics, the fluid should be warm. [ helps keep the moisture out of the sump, too ] That is why there are hyd coolers up in front of the radiator, to try to dissipate this heat. I have had my 5035 get real hot when I was digging stumps/moving dirt all day.. hot enough you can smell it.

 

[sdoubledub]

Thank you Jerry, appreciate the response and knowledge. I went out this afternoon and fired her up. No F indicator on, and it operated as it should (at least forward and reverse anyway). Is there any way to prevent this in the future, maybe by spraying a coating of some sorts? Really a bummer because we got whacked pretty good on Friday and I could've made a good chunk to help pay for this beastly blower! Not sure how much you got up there, but isolated areas here got almost a foot. Curious what shear bolts you use for your blower, the factory ones are pretty pricey. I've been using grade 5 bolts that I grind at the same spot as the factory ones, but was wondering if I'm being penny wise pound foolish.

 

[JerryK]

Thank you Jerry, appreciate the response and knowledge. I went out this afternoon and fired her up. No F indicator on, and it operated as it should (at least forward and reverse anyway). Is there any way to prevent this in the future, maybe by spraying a coating of some sorts? Really a bummer because we got whacked pretty good on Friday and I could've made a good chunk to help pay for this beastly blower! Not sure how much you got up there, but isolated areas here got almost a foot. Curious what shear bolts you use for your blower, the factory ones are pretty pricey. I've been using grade 5 bolts that I grind at the same spot as the factory ones, but was wondering if I'm being penny wise pound foolish.

I bought some shear bolts from Mahindra and also made a bunch out of bolts [ bought bolts online with a long enough unthreaded shank, ground a grove in them in the proper spot, and cut the threaded part to length... kind of what you did ] . I have moved a lot of snow, but have never had to replace one yet. This is only the second year I have run my blower. If you search back in these posts, you will notice that I had to do a bunch of mods on my 2555 to keep the snow out of the air cleaner and block the radiator some to get it to heat up enough in the winter. That big 78" front blower really blows snow, but a lot of the fine stuff just gets sucked into the engine area by the over generous radiator fan they put in the 2555. I have never had trouble with my HST pedal switches.... [ knock on wood ] I would not spray anything on them ... though. I also put a split pipe on the blower cutting edge I bought from Gaylord Machine.

 

[Jabonee]

Water in the pedal plugs under the floor. Big issue with that tractor. Also update for that tractor for plug under hood. Mahindra will notify you if your unit is affected. Don't ignore it.

 

[sdoubledub]

Update. Jabonee, thanks for the input. On early builds (mine) there is a problem with fine snow or pressure washing. Apparently the plug modules on the right side of the firewall to the engine compartment should be sealed off with weatherproof tape. Also, JERRYK provided a link to another hst problem, not sure if they are connected, so posting this for future users. Not only did I have the forward reverse issue, I also have the hydraulic fluid out the weep hole. Seems mighty coincidental. Anyway, the other user had to have his hst replaced. We shall see.