2008 White LT5000 with 50" deck (MTD) with hydrostatic transmission. I had a main crank oil seal leak, so I replaced it and added new engine oil. I fired it up and nothing was leaking. This was the first time running since last season. A few days later, when I press the throttle pedal, it starts to creep but as I press it further, the pedal resistance disappears and the tractor stops moving. It will return if I back off the throttle pedal all the way, and then lightly press it, but if the problem persists if I keep pressing the pedal forward. This makes it very annoying to drive, and almost impossible to climb a slight hill. If the land is flat enough, and you maintain a light pedal press, the tractor will slowly get up to top speed, but this is the only way it will go fast. I'm not sure if maybe oil leaked onto the drive belt or if its a transmission issue, or if it simply needs adjustment. What do you guys think?
If the belt is oil soaked it could cause slippage I would replace the belt, and clean any oil residue off of the pulleys and see what happens. If the tranny isn't making unusual noises then it is probably fine.
If the belt is slipping on the tranny drive pulley you loose hydraulic pressure through the pump therefore no resistance to the movement of the swatch plate inside the tranny.
OK, that makes sense. The dipstick still looks full, but there is what looks like oil on some of the components down there. The belt doesn't feel slippery though, and my thinking is that it would get tighter as I move the idler pulley (by pressing the gas pedal), and would slip LESS, but maybe that's not the case.
I am assuming a hydrostatic transmission. What you are talking about could be the vari-drive system. How about a model number from under the seat if it is there so I can see exactly which drive system we are looking at.
Not hydrostat at all. that is the vari-drive with the single gear forward reverse. You should have a lever that had R-N-F. If both belts are not in good shape and if replaced at the same time will cause operation issues. There is a sliding pulley between the two belts that needed to work properly, and make sure there isn't a groove worn into it someplace because that will cause speed change problems.
Also look for a groove worn into the engine pulley. Because of the cut angle on the MTD belts will bottom out in the groove worn into the engine pulley which will allow slippage.
I'll check for that too. I know for certain that the oil is leaking out. You can see the trail of spray as the engine is turning, and the oil level is dropping way too fast. I will replace the seal, and go from there. Let's assume there is oil residue on the belt and that was the cause of the throttle issue, how can I remove the residue from the belt? I might try dish detergent and if that doesn't work brake cleaner or engine degreaser. The last two probably aren't too great for rubber, but I think it's worth a try if the alternative is just replacing the belt anyway. What do you think?
