I have the lift off assembly of a 3760 bissell revolution (i use for car vacuuming) and a bissell 3750-1 lift off vacuum assembly and carriage.
My wife was vacuuming with it one day and it smelled like burning rubber.
I checked underneath thinking the belt was worn, and found there is an male electronic plug on bottom of the upper base and a female plug where it latches to the carriage (transfer power to motor and light?).
Those 2 connectors were melted away.
Ive looked thru many different websites and cant find those connectors anywhere.
The vacuum works excellent, except for this.