Bought a Rib last year and the Tacho has never worked, now that I have been trying to sort out the correct prop size its obviously essential.
However a garage told me the tacho was faulty last year when the boat was being serviced and it was never fixed. So bought a new tacho this week and low and behold the bloody thing still doesnt work. So it seems i have two working Tachos now, argggh!
Anyhow bought this one as a direct replacement
MERCURY 6000 TACHOMETER REV COUNTER | eBay
Needle doesnt move at all be it off, on, or started, set it to the 6 pole setting and wired it up positive, negative and the pulse.
I checked the terminals and they are all corrosion free, can someone offer advice on checking the obvious. Will test there is 12v tomorrow, but if its got a healthy power supply what else do i need to check.
My battery is being charged also while the engine is running as the voltage increases on my fish finder display, as i know that could point to another problem on the merc with a tacho not working.