In an effort to replace wiper blades I pulled the aim back as much as I can. In doing so I accidently got the tension spring unhooked (don't know how it got loose) from the arm head. Now I have difficulty to get the hook back as it was because I am unable to pull the spring enough - with a long nose plier - to get the hook on again, even with the arm off the motor housing.



I need advice on ways to get the spring hook back on again. Thank you.

 

There are Wiper Arm Spring reinstall videos on Youtube for other brands of vehicles using Drum Brake spring Plier. For one thing, I am not sure that the "anchor" hole on my W126's Wiper Arm (which looks like just a "dent" on the surface) is deep enough for the plier to get a solid hold and I don't have a such plier in the garage; for another, I wanted to see if I can use whatever I have and get the job done. So here is a list of what I used:

(1) A household wire cloth hanger - make a long hook with the spring.
(2) A piece of scrap wood, about twice long that the wiper arm
(3) Left-over screws and bolts+nuts
(4) Typical household tools

From the following photos, you get the idea how it was done from the setup on a foldable bench:






Now, the wiper arm with a new blade is installed on my 1987 W126 420SEL which is ready for the winter.