It has been Porsche instrument reconditioning time around here for a while. Above is a typical Porsche 911/912 multi-gauge unit, taken apart, cleaned, gauges tested and OK, and ready to go back together.
This is a typical before and after picture. The temp gauge unit on the left is pretty much what they look like when I get 'em. The multi-gauge unit on the right is what they look like when I'm done working my magic on 'em.
Here are two pages [of six] that I did on the first 912 speedometer I reconditioned. I make these illustrated how-to notes for ME on EVERY different instrument I get in for reconditioning. Keeps me from having to re-create the wheel the next time I get this type unit in. My speedometer rebuild "notes book" is well over 100 pages long at this point...
I believe in TEST SET-UPS for nearly everything I recondition. This is a set-up to test a VDO tachometer. Four cylinder VDO electric tachs indicate TWICE the RPM of the input. So if I set the drill at 1000 rpm, the tach better read 2000. This tach, from a Porsche 912, DID read correctly. Note that I tested it before I disassembled it for reconditioning. It looked pretty nasty and had obviously seen better days.
All five reconditioned units, ready for another 51,596 miles in a Porsche 912. Even the average egocentric Porsche owner would love 'em! HA!
City Car Design
5 years ago