shifting

picked up a 72 ct 70 3 speed it shifts up fine it seems but when i go to down shift it wont do anything it will stay in its higher gear an then if i tinker with it i can get it to down shift is that something i will need to split the cases for or could it be an adjustment could it be a...

Picked up a attex awhile back runs good and I even have the recoil for it but the transmission slips.What can be done for rebuilding these Thanks

Bought a used tt500 and seems to be stuck in high gear and not working in the low range. Any suggestions would be appreciated before I tear into it. Thanks