VDO tach installation for 912?

[avidflyer]

Hi all, can anyone tell me how to hook up my VDO tach to the two wires on the 912 Rotax? This tach does not have the built in hour meter. Thanks. Jim Chuk

[Dave S]

Jim,

There should be a blue and a white wire coming out of the engine for the tachometer. I do not believe it matters which one you consider the signal output and signal ground because it is a simple alternating current output with one cycle per revolution although I believe I used the white one for the signal input to the tach and the blue one for the signal ground. Your tachometer and tachometer instructions should identify one terminal on the tach for "signal input". one of the two wires from the engine goes to the signal input on the tach - the other goes to the ground on the tach.

Here is where I will be lost - I do not know if you have a battery power supply to the VDO tach or not - if so - there are more than two places to hook up wires to the tach - that will need to be determined from the instructions that should be with the tach as to which terminals are for the battery hookup. If there is a red wire coming out of the tach - it is likely the battery power input. If you have a black wire out of the tach - it is probably to ground the tach to the airframe

Sincerely,

Dave s

[avidflyer]

Thanks Dave for the reply, I don't have the instructions for the tach, I got all the instruments and engine with a parted out plane. I don't have any wires comming out of the tach, only the spade connectors on the back. Thanks, Jim Chuk

[kitfox2009]

Hi Jim
I just "Googled" VDO tach installation and there are a number of files detailing the install depending which tach you have. The address ishttp://www.egauges.com/Inst_PDF.asp. Hope this helps.

Good Luck

Don