Hello, I am trying to help with a VDO tach on a Deere 2950. I need to know the number of pulses per engine revolution the tachometer receives from the electronic sensor on the cam shaft. Really appreciate any help. If I knew the number of teeth on the gear that the sensor picks up from that would help. The dealer and manual don't seem to spec it.
I tried looking on jdparts.com but there are quite a few options depending on whether the tractor has an open-operator's station, sound-gard cab, sound-gard canopy, etc. Also, a couple of dash layouts. Sound-Guard cabs have an electronic readout for the tach (as my 4250 does), however the open station tractor's have a mechanical gauge that shows engine RPM and ground speed. (Is that what you meant by a VDO tach??) Didn't see much on there that helped I'm afraid. Andrew
Thanks for replying. The tach or tachometer is an analog pointer type that indicates engine RPM. There is a pulse generator on an idler I believe runs at half the engine speed. But I need to know how many pulses it puts out to the tachometer for each engine revolution.