2005 Troy-Bilt Bronco with Automatic Drive and Cruise - Drive problems after extended use

[TylerFrankel1]

Hello All! Recently picked up a 2005 Troy-Bilt Bronco on the side of the road for free. It had sloppy valves that were making it hard to start. Easy fix! Unfortunately I immediately suspected compression release, which led me to tear apart the entire motor. Had to replace the sump gasket as a result. It also has a rusted out muffler (I don't care), and noisy brakes (also don't care). Got a new battery, changed the oil and filter, and put some new blades on. There were big holes in the deck that I patched with sheet metal, nuts/bolts (I have no welder), and calk. So far, it's been pretty good. Well recently I took it and cut some grass, and the old cracked drive belt died. No surprises there, it looked original from 05. I put a new one on, pretty sure I did it alright, but that's where some strange things started happening.
After I put the deck back on after the new belt was installed, it would move around fine until the PTO was engaged. Then it slowed down severely and wouldn't go uphill until I cut the blades back off. Never really figured out why, as it somehow 'sorted itself out' after I threw it in and out of gear and turned the blades on and off a few times. Well after about an hour of mowing, it started behaving similarly again. It would barely move with the blades on, and was weak even with them off. I stopped using the mower for about 1 hour, got back on and it was fine again. I can't figure out why. The engine isn't bogging down at all, to be clear. Just it feels almost like the trans or pulley is losing power. Which makes no sense, because the belt seems to have plenty of tension. And it went fine for about an hour. I suppose the transaxle could be going bad, because I may or may not have accidentally thrown it into reverse while going forward a couple times, but its strange that it worked fine for so long if that is the case.
I also somehow managed to get one of the PTO engaging wires caught on something in the deck which temporarily prevented it from engaging, but I think that was from blowing it off with my leaf blower. Hopefully that's a fluke that doesn't happen again.

Anyway, I just wanted to see if anyone else had any experience with a transmission behaving this way. Thanks!

 

[ILENGINE]

Can you supply us with the model and serial number from under the seat. there are so many different configurations that we would like to be able to se what you are seeing. From your minor description sounds like you have the single speed transaxle with the go pedal or the speed selector. If so did you just change one drive belt or both, and did you use an OEM belt.

 

[bertsmobile1]

Welcome.
To answer your question we need a little more information
In particular the numbers off the ID tag under the seat.
It could have a variety of different trannies

 

[TylerFrankel1]

Can you supply us with the model and serial number from under the seat. there are so many different configurations that we would like to be able to se what you are seeing. From your minor description sounds like you have the single speed transaxle with the go pedal or the speed selector. If so did you just change one drive belt or both, and did you use an OEM belt.

It is a single speed with a go pedal, so I can make it go what speed I want by how hard I press it. The model number is 13AJ609G76637746. S/N 1D065H10105 000003. I replaced only one drive belt, the other looked to be in pretty good shape.

 

[ILENGINE]

Normally the belts need to be replaced in pairs because they sync with each other due to the variable drive system. Also something else that occurs is the pulleys will get grooves worn into them that will prevent the belt from gripping. So check the pulleys for grooves especially the engine pulley.

 

[TylerFrankel1]

Normally the belts need to be replaced in pairs because they sync with each other due to the variable drive system. Also something else that occurs is the pulleys will get grooves worn into them that will prevent the belt from gripping. So check the pulleys for grooves especially the engine pulley.

Gotcha. If this happens again I'll replace the other. Curious that it took an hour for the issue to show up. I don't think the pulleys are grooved, but I'll check again. Side note I think most of the damage/wear on this mower was actually caused by sitting around, not lots of hours. It seems fairly low hour to me. No hour meter there, but the damage has been dry-rot and rust except for the valves.

 

[ILENGINE]

May have to do with belts heating up. the engine pulley is a big culprit for slippage and doesn't take much of a groove to create a bottoming out effect especially with the flat bottom MTD belts.

 

[TylerFrankel1]

May have to do with belts heating up. the engine pulley is a big culprit for slippage and doesn't take much of a groove to create a bottoming out effect especially with the flat bottom MTD belts.

Thanks! I'll look carefully at each pully and see. I think it must be heat related since it only happened when ran for a long time (and right after installation very briefly, but who knows what that is).