Gordonmc
Active member
The electronic tachometer on my boat didn't work when I inherited it. Having bought another one I find it doesn't do the business either, so I suspect the wiring up was wrong. Can anyone point me in the right direction?
On the old unit there were three wires, power which went to a post marked "I", neg. earth to "G" and a third coming from the alternator to a terminal marked "S".
The alternator does not have a "W" terminal, the wire goes through the casing into the internals, I suspect it is soldered onto one of the field windings.
When the key is turned the tacho needle moves from its rest, but doesn't register when the engine starts. Fiddling with the calibration sees the needle shoot to 25,000 revs whether the engine is turning or not.
Is the wiring wrong? Should I check the alternator conn ection before going any further?
Any tips appreciated.
On the old unit there were three wires, power which went to a post marked "I", neg. earth to "G" and a third coming from the alternator to a terminal marked "S".
The alternator does not have a "W" terminal, the wire goes through the casing into the internals, I suspect it is soldered onto one of the field windings.
When the key is turned the tacho needle moves from its rest, but doesn't register when the engine starts. Fiddling with the calibration sees the needle shoot to 25,000 revs whether the engine is turning or not.
Is the wiring wrong? Should I check the alternator conn ection before going any further?
Any tips appreciated.
