Posted by Alan Bowes on January 23, 1998 at 23:27:48:
In Reply to: Slow windshield wipers posted by Pat Fought on January 23, 1998 at 07:31:47:
TM 9-8031-2 / TO 19-75-A-100 Power Train, Body, and Frame provides detailed instructions for overhauling vacuum-operated wipers for an M37. The degree of complexity and precision is rather impressive for such a simple-appearing gadget. The most typical problem with vacuum wipers is when the paddle plate seal materials becomes worn or hardened. There are also a number of places that can develop leaks. If you can find a good sealed-up NOS repair kit, you might try overhauling them yourself, but get the manual first, since there are several "gotchas" involved. The overhaul parts kit number is 7735526. There is also a repair kit 14-K-280, which contains tools and measurement/go-nogo gages.
Also, check all connections and hoses for leaks. You might try pressurizing the vacuum line with about 10 psi of air pressure and checking for leaks with a spray bottle.