Rev Counter - Fault diagnosis?

[neil1967]

The rev counter on my Perkins 4108 engined Oyster 406 does not seem to work. The engine is fitted with an alternator (vice a dynamo) and the rev counter would appear to be fed directly from the alternator. What output should I be looking for from the alternator or what input to the rev counter? If it is the rev counter that is broken, is it worth getting it repaired ( and if so where?) or should I just buy a replacement?

Thanks

Neil

 

[cliff]

Check all the wiring and connections - output from the alternator (the "W" terminal) is AC, the tacho is a glorified pulse counter / frequency meter calibrated to indicate RPM controlled by the alternator RPM via the AC output ("W" terminal) Tacho needs signal, power, ground and lights (if illuminated).

Check the signal, power and ground leads and connections also the fuse if fitted.

 

[little_roundtop]

I realise your rev counter is probably not a Faria type, but they have some useful troubleshooting info for rev counters here: http://faria-instruments.com/site_manuals/IS0100_Tachometers.pdf

 

[neil1967]

Most useful - thanks for the advice.

Neil

 

[maxi]

Buy a Tiny Tach, available on-line at approx £43. Apart from a 12v power input, the sensing is via one of the fuel injection pipes -very very easy to install.