suburban sf 42 furnace noise

Ok that did the trick the finance now runs\burns quite. However when I first installed the unit and tested it, the heater would fire up like normal but then just shut off. Not going through its normal cycles and I noticed that it was getting really hot, so I checked the only thermo switch I had access to on the back of the heat exchanger. It seems to be operating fine allowing current though. It was blowing air around the heat exchanger and exhausting gas out the side at a good rate. I got feed up and I put everything back together and gave up for the night. Went out this morning and tried the heater just for fun and it worked perfectly. Go figure!