Here's an oldtimer's trick. There is an open hose port on the wiper motor, where the air gets sucked in to operate the swinging paddle inside the motor. Attach a piece of vacuum hose to this port, and submerge it into a can of lightweight tuneup oil like Casite or Wynn's Friction Proofing, etc. Even Diesel fuel will work if that's all you have available. As the vacuum sucks the fluid through the wiper motor, it will clean up all the gunk inside and just burn it along with the fuel mixture from the intake manifold. The engine will smoke a little for a few minutes, but no harm done, as the additive will help dislodge any carbon on the intake valve stems on the way by. BTW, this also works on the vacuum-assisted shifters on late-40's Chevy cars.
Jerry
