First my bill of sale says l976 model  20/mh. It seems somewhere on truck i saw 1975. What is the make of furnace and model of futnace?  Problem is pilot light won't stay lit!  If you turn up stat right after lighting will run. Once setpoint is reached pilot dies shortly thereafter! Thanks

I think your thermocouple on the pilot is shot.  The pilot flame warms this and it generates a minute electrical voltage that keeps the pilot on.  No voltage and the valve shuts the pilot off for safety. That is why you hold (or pull) an override switch on for 15-20 seconds while first lighting the pilot. They seem to wear out fairly often.  Go to any good RV supply store and they will have inexpensive replacements that fit all the usual brands.  Marine stores also have them. They come with instructions and are easy to replace as a do-it-yourself project.     Bob

Has anyone found a source for a replacement blower motor for the Coleman furnace (Model 4324-729).  My furnace blower was occasionally squealing and after removing it and pulling it apart, it appears that the shaft bushings/bearings in the motor are the problem, so would like to replace the motor. Thanks, Al