TACH me back to simpler times.

Calling all mechanics. I have two Perkins 6 354 turbos and the gauges were getting pretty crusty so I changed them out for new Faria's and because some were not working anyway. Problems: alternator driven tachs just sit there and look at me, nothing. Alternators tested about .5 amps. Got new Napa oil sending units but gauges peg out to 80 when engaged and stay there when started. Back to 0 when key is off. Any ideas??? Mahalo Kevin

Do the senders match the new gauges?

Terry, both gauge and sender are 80 PSI.

Is there a setting dial on the back of the tachs? If so, you need to set that dial according to the instructions that should be with the tachs. Do the new tachs have the same exact wiring hookups? Can you take a picture of the back of the tach as it is installed and post the picture?

I just replaced both of my tachs for my Perkins 6.354's naturals...I used the V 3 tachs that are direct replacements for the originals. I had to hook one or two extra wires up so the upper station tachs got power...