Kenmore series 90 electric dryer shutting off

[cardr]

I have a Kenmore series 90 electric dryer that is shutting off after ~ 5 minutes if the fabric temp is set to high.  It will start back up in ~10 minutes or so after cooling off.  I've taken the back off and cleaned everything out.  There is great air flow.  If I reduce the temp to medium high it will run a little longer before shutting off.  Right now it's on Medium heat and has been running for a while.  I performed a continuity check on the thermostats and heating element.  All were good.  I only saw two thermostats I think.  One near the heating element, and one by the blower motor.  Also, if I just set it to air only it will run forever, so to me the electric motor is fine.  What would cause it to over heat, or is another thermostat bad?

Thanks for any help.

Model 110.64932200

[schaffersapplian]

Sounds like your dryer motor is getting hot and shutting down, and taking a nap.  The Hi temp thermostat on the bottom of the heating element, and the cycling thermostat on the blower have nothing to do with the machine actually turning the drum... just heat.  Now you have a thermal cut off mounted on the upper portion of the heating element, witch is a fail safe if the lower thermostat fails.  If that were bad, it also would not shut down your motor, Just no heat.  The white thermal fuse mounted on the blower is also a fail safe to prevent dryer fires as well. This is a non resettable part. If it fails your machine will not run at all. I would measure temp out of the 4" vent in the rear of the dryer with no clothes in the machine. It should be no more then 170ish at its highest point in high heat, timed dry.  Is your failure consistent with time dry and also auto dry?

[cardr]

It doesn't matter if it's in timed dry or auto sensing.  It lasted about 3-4 minutes on high heat.  I understand what your saying about the motor being independent of the heating element.  However, if the dryer is on high heat it lasts for 2-3 minutes.  If I switch it to medium heat it lasts 6-10 min.  If it's on medium heat it lasts for ~ 20 minutes.  I now have it on low heat and it's been running for ~20 min and still running.  To me the motor is fine.  Any other suggestions?  The only time it shuts off is when there is high heat.  I tested the heat out of the back and it's ~165F

Any other suggestions?

Thanks for your replies.