no heat
There are lots of reasons why you might not be getting any heat. I would check the following:
(Being very careful of the voltages involved, even a disconnected dryer can still have lethal voltage in the capacitor.)
1) Is power getting to the machine on both legs of the supply? You can check this at the circuit breaker box, the outlet and the cord where it comes in the back. It is possible for the motor, timer, lights, etc. to run if only one phase is getting to the machine.
2) Is the internal wiring all properly hooked up? Since you had to figure out the belt by yourself, maybe the old one snapped and took off a wire or connector when it went?
3) Is the heating element ok? You can test this without taking it apart - just check the resistance. It may be very low - but if there is complete resistance (0 on a digital-multimetter, infinity on an analogue) then the element is broken or an overheating thermostat you can't see has opened. Before you check the element, make sure you disconnect at least one wire going to it. If you don't know how to do this, best ask someone to show you.
4) There are safety thermostats, door and lint filter interlocks *and* temperature controlling interlocks built into dryers. If any single one fails or "jams" then the heater won't work...but the fan would continue. Most units I have seen over here in Europe and the 'States before 1980 have at least one safety thermostat located in the airflow somewhere away from the heating element - easy to overlook it.
5) A switch or (oh my paws and whiskers!) the timer have failed. This one can be nasty. Just about everything else hasn't really changed in the last 50 years or so...but that could be interesting.
6) You might have - don't be angry - overlooked a setting on the unit and it has been "told" to only air fluff...
Anybody think of anything else?
Good luck - oh, a shot of the wiring diagramme or a couple pictures of the wiring harness in all locations and that might help us figure something out, too.