My front wipers have been acting funny for a month or two and have finally stopped working all together. The first symptom was that the wipers seemed to be moving extra slow in both speeds, with very little difference between the two. Now they just stopped (mid-cycle). I assume I need a new wiper motor, but I thought I should throw it out there in case there's another possibility. I checked the fuse. The rear (wagon) wipers have worked fine all along.

I had the same problem on my 86 240 a bunch of years ago and one of the magnets had come loose inside the case. I also just epoxyed the magnet back in place and it has been fine ever since.

The 240 wiper motors have a history of problems just as you describe. The inside of the motor becomes rusted and the magnets start to let go of the casing and bind on the armature. You can replace the motor, but they're not that difficult to repair. Basically you open the casing, clean up all the rust and epoxy the magnets back into place (in the original orientation opposite each other). Be careful during reassembly as the brushes and their springs can be a bit fragile.

For more information look in the 700/900 FAQ feature section and do an advanced search in the archives.
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Dave -not to be confused with a real expert, just goofing around at this

could be the motor was giving up but I would look at the shaft bushings..
sounds like somethin mechanical seized up or was in the process of seizing
and maybe killed the motor? But if you disconnect the assembly at the motor
and hit the wiper switch does the motor now run? If so.. it, of course, is good
but a pivit point in the assembly is frozen.. most likely the shaft bushing..
had the same problem on a 74 VW bus. Luckily I didnt fry the motor it just
couldnt move the wipers due to the shaft on one of the wipers being frozen.
The shaft.. BTW .. is the thing the wiper itself attaches to and the shaft goes
through the car body where the motor and mechanical assembly reside.
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vw bus site w/ Volvo section - http://www.geocities.com/vw_bus_74/index.html