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rmp
24th April 2004, 08:45 PM
Just finished installing a tacho in my Defender. Here are some tips:

1. I didn't get a handy white/grey wire hanging around loose in the instrument cluster. Had to splice into the yellow/pink wire in Pin 19 on the black ECU. Didn't cut the wire, burnt it back with a soldering iron.

2. The ECU pins pull straight off, there are no clips or pressure points. Gently levered off with a screwdriver.

3. It is possible to shove a cable all the way from the instrument panel to down to the clutch without removing lots of trim.

4. Rev cable was routed through a drilled hole in the ECU compartment, around the outside of the floorwell, and then up.

5. Moved all the instruments along one after removing the clock. Had to extend two wires; did this at the factory splice thus moving everything beyond that along one as opposed to each wire.

6. It's fine to splice the existing positive wire that powers the fuel gauge and engine temp. The old one from the clock can be used, but it is live all the time so it's not ideal.

7. Get the screw-on white rings round the right way. Doesn't do up otherwise, can be a pain!

8. Once fitted, the revcounter may not be accurate. To calibrate, we put a bit of white tape on the flywheel, laid underneath the car and used a strobe gun to measure RPM. The VDO gauge has a little screw you can turn which is used to calibrate. Mine was reading 900rpm idle which was 150rpm too high. Also checked at 2100rpm.

9. Get all the instruments horizontally aligned before you replace the dash.

10. There are four screws to remove the dash. It's just not the four you think.

11. It may be a 30-45 minute job for some sort of superhero autoleccy, but for myself and a friend it was 4 hours. We didn't make any significantly time consuming mistakes, but we were careful and thorough.

Hope this helps someone, I couldn't find much on the job other than "it's easy and you just route from pin 19" before I started.

For those interested the VDO revcounters are available from Croytec or Low Tension, both in the UK, for about 55 pounds plus shipping. Only other parts you'll need are some spade plugs and say 2m of automotive wiring. Tools are a drill, wire strippers, teflon or electrical tape, soldering iron, spanners to disconnect the battery, Philips head screwdriver to remove the dash.

And the Defender does 2100rpm at 80kmph. Friend's vehicle has smaller tyres and does 2100 at 110, because he has a GKN overdrive. Hmmm....