I have an older Rheem heat pump. The blower motor on the outside unit stopped running. It seemed to only run at about half speed for a couple of minutes then get hot and stop. I replaced the motor and both capacitors. This motor runs at full speed but gets hot and stops after a couple of minutes. The compressor sounds like it is still running. Any ideas?

Since you have changed your capacitors and the motor still fails it sounds like you have a bad motor. On all motors there are bearings, some are oilable and some are not, if it can be oiled you can try that, the old lubricant turns to a varnish like substance after many years and causes a drag on the bearings causing it to overheat and stop running.
I would not reccomend you operating the A/C untill you remedy this problem as it can cause the compressor to fail from overheating.