Kad 32, Tacho fault

[enterprise]

I have twin 2007 Kad 32's, during our last trip we noticed a problem with the starboard Tacho, needle kept dropping to zero accompanied by an alarm warning.
Thinking the engine had stalled we tried to restart it, only to find that it was still running ok, even so the tacho responded and read correct untill we berthed.

We have used it on a number of occasions since and other than the gauge fault the engine is running faultlessly.

I'm sure it's only going to be a minor electrical fault, connections or gauge etc but can anyone tell me where the signal is generated for the tacho?

PS the guage has power because the LCD hours displays are currently working.

Cheers Guys

 

[volvopaul]

The alternator generates the signal, maybe you have a faulty tacho the ones with the lcd display dont have a long life at all, though its usually the lcd hours display that fails, not your way around so id check for any wiring faults on the 16pin plug into the plastic box.

 

[alt]

As said above, the tacho gets its signal from the alternator

Now, if the alternator is failing to produce power, the alternator light and alarm will go off.

Put 2 + 2 together? Is your alt belt slipping? Or is your alt on its way out?

 

[bethany]

I had a similar problem with my ad31. The problem was the main electrical connector on the engine had come adrift. Refitted, problem solved...
Good luck.

 

[[2068]]

Needle dropping to zero + Alarm = dodgy alternator or dodgy alternator wiring.
Start with the terminals and wires round the back of the alternator.

If it turns out to be the alternator, you need a Valeo A13N234 or equivalent.

 

[Peanuts]

Hi
As you should have gathered by now the signal for the tacho comes from the alternator. I had a problem similar to yours and it turned out to be the 1/4" spade terminal on the back of the alternator had fractured just inside the push on connector, so visually it looked OK but checking the terminals showned up the problem. It will be easy to check as it is only a push on lucar connector on the back on the alternator.
I hope this is of some help.

 

[enterprise]

Cheers Guys,

Will look at the main harness connector and alternator connections, will also swap gauges with the port engine to see if it's the gauge at fault.
Many thanks

 

[enterprise]

Result

Took a look at the alternator today, guess what, found the yellow wire at the back hanging down, Forum comes up trumps again, fault now sorted.

Cheers Guys.