Here are your parts
Replacement parts for WHIRLPOOL LER4634JQ0 | AppliancePartsPros.com

Here is your wiring diagram
http://www.servicematters.com/d...0Sheet%20-%203406688.pdf

I am assuming that the cut-off you replaced is the one on the blower assembly (kills power to the motor).

The most common cause for this blowing is a dirty vent system or the vents louvers not opening correctly.

Another possibility would be the operating thermostat Item 20 Section 3.

Undo the dryer from the exhaust
Run a load
If you do not want lint in the house.
Take a pair of pantyhose, put one leg into the other and attach this to the dryer exhaust.
Leave enough room behind the dryer so it can blow out like a windsock.
Run a load.

Both the above will allow you to check the air flow and temp.

Check that the temperature changes with the different temp settings.
If not could be the operating thermostat or a grounded element.

Check that you have a strong air flow.

NOTE: You could unplug the unit, remove the wires from the cut-off, short them together, tape them up so they cannot short to the frame and then run your tests. This will at least save you from replacing another cut-off.

Do not leave the unit like this, as the cut-off is a critical safety device!!!
Running without it can result in a house fire.

OK, that is a different kettle of fish.

The reason they include a hi-limit with that thermal fuse is that the hi-limit should have shut the heater off before the fuse can blow. Therefore they assume that the hi-limit is also no good.

Check that the heater is not grounded/broken. In some circumstances it will heat and the thermostats cannot control it.
Remove both wires from the heater.
Measure the heater with a meter should be around 10 ohms.
Then measure each heater connector to the case, both should be open (infinite ohms)
Often you can see the problem by inspecting the heater.

Next check the air flow. The air is sucked over the coils, through the drum and pushed out the exhaust. Any large air seal gap in the path to the blower will suck in room air, this is seen as a cooler temperature by the thermostat on the blower so it overheats the heater. Also make sure the air flow path is clear re the lint filter is not coated with fabric softener residue etc.

Do the vent check and clean/check the blower wheel. Just had a person with the same problem and he found a cracked blower wheel.

If all OK I would replace the operating thermostat.