Monday, August 29, 2011

BMW e46 sub frame bushings

Older e46's have an infamous thump noise coming from the rear when you hit or let off the gas suddenly. The bushings for the differential and sub frame get old and don't dampen torsion movement as well as they used to. Sometimes the extra movement is enough to crack the sheet metal body if you drive the car hard enough. (There was a class action lawsuit about this defect in e46's.)

To get rid of the noise and prevent future damage, I did a sub frame drop and replaced all the bushings. It took me two days just to get to the point in photo #1 and a few more to figure out how to remove the old bushings. I first started to with a barbaric drill/jigsaw/hammer/chisel method, which was fun at first, but was too much work. I got my dad to help me fabricate some custom tools to pull the rest of the bushings out and push the new ones in.

Total cost was $150 in parts (6 new bushings) and about 4 days of work. I'm sure an independent shop would charge around a grand for this job. Definitely not an easy DIY. I wouldn't want to do this one again :P

I used this DIY from E46Fanatics as a guide. Check it out if you want to see the complete step-by-step.

Thursday, August 4, 2011

Pentax SMC-DA 21mm f/3.2 AL Limited

This little pancake lens is my favorite. That's probably why taking it apart was so scary. I bought the lens about a year ago, and now it's having trouble focusing to infinity. It has happened to other people too. (PentaxForums)

Basically, the focus mechanism gets loose over time and doesn't retract the glass elements far back enough to focus on objects farther away. Here's a look at getting to the internal focus rings: