I was quoted 2.5 hours labour to replace the wiper motor. Does this seem reasonable? Is it just lengthy but not complicated and something I could potentially do myself with patience? I would like advice regarding replacing the wiper motor myself. Thank you veddy much.

 

Also, as this is not the first time it is being replaced, should I be concerned about what might be triggering the death of the wiper motor?

 

It's not difficult, just a bunch of screws and a few nuts, but I have no idea what might cause multiple failures.

 

I have an 89 300E, mono wiper. The job is easy, just time consuming to take the upper dash apart.
Check all your wiring and wires to the motor to make sure the contacts are good and no wire is
a short.
Also when you change the motor, lube the gear housing for the wiper. The plastic gear will bind with
age since water and debris gets in through the shaft of the wiper. It is outline here somewhere.
If the wiper linkage is binding, like mine was, the wiper will be slow causing a load on the motor.
I kept blowing fuses and thought about uping the amp on the fuse, mine was 16A, spec. I
didn't, I took the time to lube.

Check to make sure the right fuse is in for the wiper and that it wasn't increased. Also, when you
change the motor, lube the gear housing and linkage so it won't load the motor.

Hope it helps.