Here are your parts
Parts for Frigidaire FER311FS0 Dryer - AppliancePartsPros.com

Here is the wiring diagram
http://manuals.frigidaire.com/p...df/Webster/131847200.pdf

Problem should be either electrical or mechanical (too much drag on the motor).

I am assuming that the motor does not start and it is not that the motor runs but the drum does not turn.

When you said you checked the voltage, did you do a live test?
Pt one meter lead on X at the timer and the other on Neutral.
You should see half the line (120 volts).
Now push the start button.
The voltage should stay constant.
If it drops much then you have a power/wiring problem.
Best to do the above with two people as it is safer.

If the voltage is OK then it will be a mechanical problem.
Manually turn the dryer in the correct direction to see how much drag there is.
You may want to try this on a couple units to get a feel for it.
Also put some clothes in it to see if it increases.
Common problem areas are the rear drum support bearing (is at the bottom of section 03).
Check the plastic receiver part of it for wear.
Also be sure it is well lubricated with high temperature grease.
Check the front glide (item 24 in section 03).
Check the idler wheel (item 23 in section 09).
Check the front door seals.

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