I serviced this Proform 795 SL treadmill in Windham, Maine on 5/8/15. The complaint was a burning smell after the treadmill was in use for several minutes.
My service began with cleaning the deck and lubricating the belt and deck which were very dry. My suspicion was that the burning smell was coming from the small motor that these Proform treadmills have due to the amp draw due to the lack of walking belt lubrication.
After lubrication the walking belt I could not detect any burning smell after running and running on the treadmill for quite some time.
It was apparent that the last repairman that replaced the drive belt was with a novice, lazy or both. To replace the drive belt one one need to partially remove the front roller. To have good access to the front roller adjustment boat on would need to move the motor control board out of the way.
The screws that held the motor control board were not started but not screwed in and the front roller bolt was not properly install causing the walking belt to be crooked on the deck. Most of the motor cover screws were also missing and was held in place with one screw.
I informed the owner that the walking belt should be replaced sometime soon. As can be seen in the images, the belt was fairly worn and starting to tear at the seam.
The treadmill was also very dirty, but as my habit it was all cleaned and polished by the time I left.