KAMD43P tacho problem

[Wiggo]

Anyone got any ideas? For a long time, my port engine periodically neglects to show any revs on either tacho on startup and after a few seconds, the alternator alarm goes off. It's definitely not the alternator, it affects both tachos (up and down), and magically clears itself after a minute or two. Something is amiss somewhere, but I can't think where to start looking.

 

[alt]

Corroded connections?

 

[volvopaul]

It could be something to do with the supercharger relay and voltage drop, thats if you rev the engines high enough to pull the chargers in.
If not that and its only at idle then I would say you have a lazy voltage regulator in the alternator and it needs to be spun over before it balances out, could also be just something easy like a damp engine bay as rust will form inside the alternators when th engines are left for long periods.

I would say that half boating engine related problems are due to lack of use and regular attention, to put it plainly were not at our local garages every day with probs like we are with boats every few months.

Check over the wiring, pull out the 16 pin plug and spay it with some electrical cleaner, also remove the spade terminals from the alternator and put them back on make sure there tight too, unfotunately you have a sealine and to be honest I get more probs with wiring on them than any other make of boat I work on, you would not believe what comes out of the factory to dealers with endless stupid faults.

 

[unit101]

Well I had a similar problem on my Nimbus. After literally months of trying to identify the problem it turned out to be a bad connection to the battery earth bolt...

Check it out - and not just on one side of the bolt - check the side you can't see!

 

[Wiggo]

Thanks, Paul, I'll give it a look over. It only happens at tickover, but now you mention it, it would always clear as the revs built up. The alternator is new, fitted with a regulator controller earlier this year and the boat is scrupulously maintained and serviced and runs regularly, so it ain't neglect. This is the last niggling problem with the boat (touchwood), so I'd like to clear it...

 

[Wiggo]

Paul,,thanks again - the multiway plug had a couple of corroded pins, so we'll see how it goes from here...