Vehicles

rv - Improving Tension on Wiper Arms

I replaced the wiper arms 4 years ago with a modern style you can actually get wiper blades for. They worked fine initially. Fast forward a few years and the wiper arms no longer worked. The blades were still in great shape the but the arms did not apply enough pressure on the glass. In the rain, the arm would move the blades back and forth only contacting the glass in a couple of spots. Finally in a downpour I had enough of not being able to see. I resolved to fix the wiper arms no matter what it took.

I knew I would be modifying the existing arms, not buying new ones. I figured I would put a strong spring on the arms and that would be it. I took off the arms and inspected how they work. Turns out the springs that provide the tension were already extremely strong. They were very difficult to get off.

So I then looked more at the pivot point. There was a solid metal shaft with nipples on both sides. The nipples fit through holes in the long shaft arm. The long shaft arm is just supposed to rotate freely around those nipples. Guess what, the area around those nipples were scored, dry, and slightly rusty. Initially I thought about lubricating it and putting it back together. But that would probably only last a few months. In summary, that pivot point has a terrible design and I don't see how the wiper arms were ever supposed to last. What was the designer thinking?

I choose to dissassemble the arms and press out metal shaft that had the nipples. I got some RC car bearings that were just the right size and installed them into the hole the metal shaft previously went through. Finally I reassembled the arm using a nut and bolt through the long arm and through the RC car bearings.

The sealed RC car bearings might have been overkill. Probably a standard bushing would have worked fine so long as the bolt O.D was slightly smaller than the bushing I.D. But hey, if the bolt ever rusts to the bearing, the arm will still pivot freely.

Now the wiper arms provide great tension against the glass again. And I don't need to worry about lubricating anything. The nut and bolt are visible, but that is a small price to pay for seeing during a rain storm.

Movies


Rusty shaft replaced with bearings and bolt.m4v
(35.8MB)


Pictures

Preview Image Size
SmllMedLrg
SmllMedLrg
Arm is stuck, fully resisting spring tension. No wonder they didn't contact the windshield
SmllMedLrg
SmllMedLrg
SmllMedLrg
SmllMedLrg
That spring provided plenty of tension, was tough getting off
SmllMedLrg
SmllMedLrg
SmllMedLrg
Note the rust on the pivot point
SmllMedLrg
Initially tried to drill out and extract the shaft not realizing it was one solid piece
SmllMedLrg
Not the machine scoring, like they wanted the arm to fail pivoting here. A terrible design
SmllMedLrg
SmllMedLrg
That is one thick shift.
SmllMedLrg
SmllMedLrg
14 mm O.D sealed RC car bearings to the rescue.
SmllMedLrg
bearings are not a press fit, they are loose in the shaft
SmllMedLrg
SmllMedLrg
SmllMedLrg
SmllMedLrg
Now pivot point works perfectly

Add Picture Comments
Contact Us | ©2014 Me | Page best viewed with Chromium