Tachos on 912/914 engines.

[cheray]

has anybody had any success in fitting and calibrating a 52mm VDO tachometer to a rotax 912/914 engine.

 

 

[planesmaker]

has anybody had any success in fitting and calibrating a 52mm VDO tachometer to a rotax 912/914 engine.

What seems to be the problem?

 

 

[thommo]

I'm have rotax tacho in stock

 

 

[cheray]

Thanks Thommo but I can't fit a rotax tachometer into my dash not enough room.

 

planesmaker, The signal delivered from the rotax signal coil doesn't deliver a signal that my 031 Vado tachometer can read, I read a post by Scott Henry back in July 13 where he had obviously been playing around with some smaller tacos, saw your reply to his post and was just hoping that he may reply to mine and I could discuss with him or anybody else for that matter any results fitting these tachos to rotax engines.

 

 

[planesmaker]

All I can suggest is to add a small diode on the signal wire. You can buy one for a coupe of dollars from auto electrician, they use them in alternators. The one I had problems with was a 3" vdo fitted to a skyfox. Worth a try. Tom

 

 

[bushcaddy105]

I use the wheel sensor fom a car ABS system to trigger my VDO tachometer. The flywheel bolt heads can be used to drive it, or a pair of steel tabs as per Jabiru setup. The tachometer simply needs to be programmed to the correct number of pulses per engine revolution. This setup totally separates the tacho from the engine ignition systems, removing one possible cause of ignition failure.