Dont run your truck with a broken bearing.

First things first...You should remove your engine and thoroughly inspect everything for damage.
Look for cracks in the engine crankcase, and carb body,header mount, etc.
You should also open up your engine and inspect the internals. Look for cracks in the piston skirt,
look for metal shavings in the crankcase and combustion chamber. Check the action of your engine bearings.
Give your transmission an inspection. Look over your spur gear (large gear mounted to the transmission)
Look for sheared off gear teeth, turn the spur gear, listen for grinding noises.
Do the same with your clutch bell.
Inspect your motor mount and EZ Start (if equipped).
If everything checks out, replace your cooling head reinstall your engine and reset your needles if neccessary.
One more thing....While your cooling head is off, look at the top of the piston. If it's a brownish color, you're running too lean and could jeapardize the life span of your engine.