My A/C starts up fine then after and hour or so the furnace blower shuts off while the A/C is still working.

You may need to replace the capacitor or the motor. It could need oiling, too. Try pulling the motor out and oiling it and check the capacitor. A weak capacitor will cause the motor to heat up and go out on the thermal overload. Since motors are cheap and you risk losing a compressor, you may want to replace the motor and capacitor and oil it every 6 months and when you install it. You can buy the special oil at an HVAC supply house for $2.00. It has a long plastic spout. You always oil a motor when you install it and make sure to clear the oil passages, first. If you have a 3 1/2 ton unit or less you probably have a 1/4 hp motor, higher and it's probably a 1/2 hp. You can go up for more durability, but not down.

A hot motor shutdown on your central air could be caused by a bad motor, a bad or weak capacitor, or a freeze up in your A/C coil due to low freon. Icing up of the coil will cause the motor to work harder and not have sufficient air flow around it to keep it cool.