Tachometers Bouncing

[jvtuna]

Have A 1997 Cc, And My Tachs In The Tower Bounce, Not Both Of Them At The Same Time, But One Or The Other. Try To Tach Up One Will Be Ok, The Other Bounces And Viesa Versa. Does Anyone Else Have This Problem, Very Difficult To Sinc The Motors When On The Troll.

[Captain Spike]

What motors do you have? I have Volvos and my Port tower tacho bounces all the time and I can't work out why.

[Tswann]

Usually erratic gauges are grounding or wiring issues. Check a couple of things. On 28s . . .

1. Under your dash up against the bulkhead there is a grounding strip that has the termination for all of the grounds. Check to make sure all of these are clean and tight.
2. On the backside of your engine(s) find the main harness. Usually when the boats are built all of the gauge wirings, senders, etc are routed to the rear of the engine, bundled up and then routed across the back of the engine compartment into the starboard rigging tube and up to the dash. Look for a chaffe point. I had a starboard tack that was bouncing and I found that the harness wired had rubbed on a rear motor mount and was not in good shape.
3. Look in the overhead electronics box where the wiring comes out of the tube and then goes up into the elephant tusk ... again this is an area of possible rubbing . . .
4. Look inside the console box up top where the wiring comes out of the tusk for any unusual routing, rubbing . . .
5. And of course look at the spade connectors on the back of the gauges. Plug and unplug them. Somentimes a crimp is not quite as tight as it should be so visually it looke good, but when you touch it is loose . . .
6. If the problem is only on one side, then swapping the gauge from side to side will tell you if the gauge is the culprit.

DC gauges can be frustrating little suckers but they all need power from the source and a stable ground to work . . .

I hope that helps.

[jvtuna]

Tswann

THANKS Tswann , I'll start looking, I have volvos kamd42

jv

[Split Decision]

THANKS Tswann , I'll start looking, I have volvos kamd42

jv

Did you ever find out what the problem was?