Monday, December 24, 2012

The Fix That Wasn't

Fixing the auto levelling control arm of our chevy venture van to pass inspection

I just brought our van to the yearly MVI where it was determined that the mechanism that levels the rear of the van was broken. The component that determines whether the van's rear axle is horizontal is comprised of an electrical unit and a mechanical arm that moves up and down as the rear axle moves up and down. Somehow that arm fell off and the tech said that I had two options:

1. Fix the auto levelling sensor and arm, which he quoted me $700 bucks for, or
2. Replace the air pressure assisted rear shocks with a set of new, non-air assisted shocks and bypass the auto leveling feature altogether. He still quoted me about $200 bucks for that

Naturally, I didn't want to spend any money and figured I could probably fix the arm for free.

This is the component from every angle showing the arm(s) that were missing
First I had to calculate how long and at what angles the arms were
AutoCad to the rescue
Plus some trigonometry. Remember the rule: soh, cah, toa...
Then I made a piece out of two component epoxy putty
Close-up of the piece that links into the sensor
Then I used that epoxy putty positive as a model to make a sand mold and cast it in aluminum
I had inserted a 1" flat iron cut and bent to shape and size before I poured the aluminum so it was cast into the aluminum knob during pouring
Unfortunately, after about 4 hours of plugging away, I bumped that darn sensor onto the ground and broke the one pice off that I couldn't fix it.
I was so mad, since I had just spent several hours, was almost done and with one careless movement I broke the $500 ALS sensor!
The only option left was to go buy two cheapo shocks ($38/each) and replace the air-assisted shocks (which I had just replaced a bit over a year ago with brand new ones). Needless to say, even though I passed the inspection with these new shocks I wasn't very pleased on how it turned out...

Impact wrench, torque wrench, adjustable wrench, socket set, drill, aluminum foundry, car ramps, mig welder, drill press, angle grinder,

2 component epoxy putty, scrap aluminum, 7" piece of 1" flat iron


6 hrs

About $100 bucks

Failure at first, success (partial) at the end although not the way I wanted it to turn out!


Post a Comment