Problems with Maytag washer after belt replacement!?

I just replaced the two belts on my Maytag washer(lat9806). After doing this it spins fine when empty but when I fill it with water it stops half way through the spin cycle. It then seems like the motor is dead. The first time I thought the belt was too tight and I fried the motor. I drained the tub "manually" (using the hose) and looked around. About an hour later it spinned again (when empty). Then I filled again and half way through the spin -- same thing -- it all stops!
Any idea what's going on?
Thanks!