Make sure there is enough spring pressure on the glass. I think the general rule is 1 pound per inch of blade? Small tension gauge or a fish scale can be utilized to measure the pressure. Other things to check is the grip on the rubber blade itself. The claw should just grasp the blade allowing movement but a hair of clearance side to side. The arm needs to be parallel to the windshield. I've seen some where the shaft in the cowling was a little off plumb; ice does this sometimes. Some parts stores that have service station supplies sell a kit with a tension gauge and blade claw rule. Just remember these cars have "narrow" refills.
