My forced air furnace does not stay lit when the heat is turned on. I climbed into the attic where it is located and had my wife set the thermostat to heat. I observed the burners light and watched the Honeywell limit switch start to do it's thing but after about a minute the limit switch clicked, the flames died and the transformer which is wired with the limit switch seemed to go dead. Nothing worked. No a/c, no heat, not even the fan. After several minutes of cooling everything will work again as long as I don't use the heat. This is an older wood frame house in Houston and I'm not sure but I believe this unit was installed in the early to mid 80's.
I could also use a schematic for this thing. I can't seem to locate one on the unit.
I believe the transformer/fan center may not be wired correctly because there is a brown wire from it that is not connected to anything and some other wires from the fan that are terminated but not connected.
Any idea where I can get the schematic ?
Is the problem with my limit switch or something else ?

Magic Chef model no: G83-1000D2C4-5 S/N: C-21074HEB
Honeywell limit switch
Transformer/fan control: MARS 240 SERIES NO. 24013

It sounds like the blower motor is not working allowing the unit to overheat and shut off on the honeywell limit. OR the fan control that turns the blower motor on is defective.