Do you always put the part of the blade that slides freely so that it points to the roof of the car when they are up as far as they can go? Also - does the washer fluid or ammonia degrade the rubber? Thanks.
I am not sure about that blade sliding freely thing so I will skip that.
Windshield washing fluid should be cause a meaningful problem and while I doubt if ammonia would cause a problem, I would not want to use it on mine.
If your wipers are working smooth one direction and not the other, then likely they are not really perpendicular to the glass when they are held above the glass, almost touching it. You may need to bend the arm to fix that.
If you’re talking about installing the whole wiper arm to the shaft you almost need a service manual to get the correct placement. If you can see a wipe pattern in the windshield you could go by that, but be prepared for a little fine tuning. Test them with water on the windshield, because they move a bit farther when the windshield is wet.
If you’re just talking about replacing the blades you can follow the instructions on the package the new blades came in.
Washer fluid doesn’t have ammonia in it, and you shouldn’t put ammonia in the wiper fluid reservoir.
Washer fluid won’t degrade the wiper blades. Time, sunlight, and dirt degrade the wiper blades.
I do have to adjust one whole arm because it parks far down onto the cowling instead of staying entirely on the glass. I thought when you pulled the whole arm off that it would look like when the steering wheel comes off with teeth to reposition it in. I need to try to guess again on setting that one correctly.
for the replacement part that attaches to the arm and holds the rebber blade, the instructions do not say which side goes up. But I do notice that one end of the rubber is anchored and the other is held so it is free to move as it lengthens out when the wiper goes from a curved shape to straight.
Some of the windshield cleaner at gas stations smells so potent, I think it could wear the rubber in the wiper blades if it gets to them.
10% ammonia has a sever effect on natural rubber. I’m not sure what your blades are made of, but you might try something else.
You have a good idea of how to install wiper blades, but if the lock breaks, the wiper is coming off anyway. I would rather do it your way to keep from waving the lock around more. Some owner’s manuals recommend that you clean the blades with washer fluid, but you won’t catch me looking for fluid when water is everywhere, especially when it rains.