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Adjusting Amphicar Wiper Linkages
The Problem: Wipers jam with possible damage to cowl area around windshield wiper pivots.
Stop the wipers at the furthest point in their sweep, by simply turning off the ignition, and check the position of the right hand “underside” arm. You want to be sure that a little bit of additional force (representing a wave or wiper inertia), pushing the right hand wiper to the outside, is not able to over rotate that lower arm past the line of the pivot. The fix is to simply lengthen the linkage from the arm to the motor. Remove the wiper arms, before you restart the system, since fooling with these linkages changes the positions of the arms on the pivots. While you’re working under there, you want to check to see that the two lower arms are coordinated. This is simply making sure that the connecting link between the pivots is adjusted to the same distance as the distance that separates the pivots. Sounds complicated, but it’s simple. With the motor linkage disconnected adjust the position of one of those lower arms to be perpendicular to the edge of the trunk compartment. I simply held a Popsicle stick along the side of the lower arm, with the end sticking out so that I could see its position. Then check the angle of the other lower arm. If it’s not also perpendicular to the edge of the trunk, adjust the length of the connecting link to make it so.
I believe that the motor drive rod length to the right hand pivot is the most critical adjustment. It’s the right pivot that’s most likely to over rotate, though the left arm could do it too. You simply have to be sure that the motor drive arm linkage length is long enough that any reasonable amount of additional rotating force is not able to force the pivot arm to over rotate and jam and, if you’ve also done the “perpendicular” adjustment, the left lower arm should also be in the correct position. Once those lower arms and linkages are correct, reinstall the wiper arms.
John Friese
67 White
67 Red