Troy Bilt Pony Model 13An77TG7666 Transmission Adjustment hints Please

tackleberry

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  • / Troy Bilt Pony Model 13An77TG7666 Transmission Adjustment hints Please
I have replaced Variable Pulley bearings.....Variable speed pulley is free, not bound up. Idler pulley is free, not bound up. Upper belt replaced (MTD OEM) , Lower belt replaced (MTD OEM). I am having problems with the speeds on the transmission. It seems it only wants to give me one speed. I have looked at the transmission lever adjustment rod. I put it in Parking brake position and adjusted the rod to fit that position. Parking brake locks properly. The rest of the speeds are indefinite. Any hints on whats going on? I purposely used all OEM MTD belts to make sure that wasnt an issue. If you have adjustment instructions by MTD please pass them on, or ones that work.
 

Rivets

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  • / Troy Bilt Pony Model 13An77TG7666 Transmission Adjustment hints Please
If it only gives you one speed your variable pulley is not moving up and down. First thing I would check is the tension on the drive pulley, one going from the engine to the transmission. Stepping on the pedal with the engine off should increase the belt tension. With the engine running this tension should move the variable pulley. Are you sure the tensioner pulley is in good condition and the tensioner arm is moving freely?
 

hlw49

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  • / Troy Bilt Pony Model 13An77TG7666 Transmission Adjustment hints Please
I have replaced Variable Pulley bearings.....Variable speed pulley is free, not bound up. Idler pulley is free, not bound up. Upper belt replaced (MTD OEM) , Lower belt replaced (MTD OEM). I am having problems with the speeds on the transmission. It seems it only wants to give me one speed. I have looked at the transmission lever adjustment rod. I put it in Parking brake position and adjusted the rod to fit that position. Parking brake locks properly. The rest of the speeds are indefinite. Any hints on whats going on? I purposely used all OEM MTD belts to make sure that wasnt an issue. If you have adjustment instructions by MTD please pass them on, or ones that work.
One too many 6 in the model no.
 

tackleberry

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  • / Troy Bilt Pony Model 13An77TG7666 Transmission Adjustment hints Please
yeah 766.the center sheeve of the variable pulley moves freely up and down..and i replaced the bearings also.
 

StarTech

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  • / Troy Bilt Pony Model 13An77TG7666 Transmission Adjustment hints Please
I would think variable speed bracket and/or varible to trans idler bracket is heavy worn and is binding. Usually the hole and shoulder spacer will wear one sided. Also this area can rust and bind too.

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tackleberry

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  • / Troy Bilt Pony Model 13An77TG7666 Transmission Adjustment hints Please
i will check that out...my idler lever seems to move freely, but I have ordered a new spring for it, but the old one is rusty, may affect its tension....the step mechanism attached to the brake pedal arm, it looks like each "speed" should rest on its own "step".. I'm a little confused on how that mechanism works to change the belt tension at the Variable Pulley. Mine did not seem to engage the next step for the next speed, so I bent the arm which rest on these steps to engage (just a little)...thinking maybe my steps are worn. it seemed to help engage each step better. The rod seems to only adjust so much and still have parking brake function.
 

Rivets

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  • / Troy Bilt Pony Model 13An77TG7666 Transmission Adjustment hints Please
As you add or reduce tension on the idler it will shorten or lengthen the belt going to the variable speed pulley. This will raise or lower the center portion of the pulley, increasing or decreasing the drive speed.
 
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