Testing the wiper motor, I got 23 rpm at slow speed and 30 at fast. The manual pP40 says that the maximum rpm is 44-48 at slow and 68-68 at fast and to replace the motor is those are exceeded. There is also a data chart on pP38 with more information that I don’t understand. Where do I measure the current in the test?
Seems clear that wipers on this motor will be slow, which maybe is not a big deal, since I don’t plan to drive in the rain unless its unavoidable.
I don’t know what a ‘first grade moving coil ammeter’ is but I would think any multimeter (including the free one from Harbor Freight) should be able to measure the draw when connected in series on with the power lead (‘supply cable’). If the draw is excessive then I think the motor will be a problem in use.
John - Manuals are not written for 50 year old cars. It could also be something else like the linkage, or even dry bearings in the motor. You can pull the end cap of the motor off easily and see what the lower bearing is like - it’s almost certainly dry if it hasn’t been lubed since the 60’s. The upper bearing generally fares a little better - IFRC it may get some lubrication from the grease in the gear box.
