CAT 3208 Tachs wiggle and die..

Is there common ground between CAT 3208 tachs as they almost simultaneously (within 30 seconds) die and recover for a bit upon start-up. Wiggled wires behind dash with no results.

Thanks in advance!

Sounds like you have electrical tachs. Have you inspected the pick up side for connection issues?

Osprey69 said:

Is there common ground between CAT 3208 tachs as they almost simultaneously (within 30 seconds) die and recover for a bit upon start-up. Wiggled wires behind dash with no results.

Thanks in advance!

Click to expand...

They would need to be grounded to work, so a single bad ground, where ever they share it, would cause this. I am not sure how your boat is wired, but I have worked on boats that use one of the engines as a ground bus (a terrible idea IMO) and that could certainly explain your issue. That said, I have been in the engine room on a Gulf Star 49 and it looked like it was well built and well thought out, so I doubt that's your issue.


Invest in a power probe, learn how it works, and you can use it to instantly inject a ground or +12V where ever it's needed. They are incredibly handy tools for 12V DC electrical troubleshooting.