Tacho issue

[Courageous]

Hi guys, probably going to turn out to be another stoopid question but I thought I'd plunge in anyhow......

With no power applied to a tacho (in this case a mariner 150 efi) should it read zero or could it give a random reading? Mine's vertical (from memory showing around 4k). I've never seen it coupled up properly as I bought the boat with a funked engine and battery. In the proccess of swapping over the engine next week and wanted to know if I need a tacho too.

Thanx in advance.

[uncle al]

if its a quicksilver tacho when you switch the ign of the tacho will show and stay at the revs you are doing at that time, and when you turn the ign on to start the obm at a latter date the tacho needle should drop down to zero

[Waterman]

Yes, the tachos on my last rib used to do this but would always return to zero after I switched the ign on again.

[uncle al]

is your obm a two stroke?

[Courageous]

Thanx guys that gives me hope! Yes Uncle Al its a mariner 150 efi 2004 vintage 2 stroke motor.

[Courageous]

Hi guys, a bit late I know but I wanted to let you know that the tacho issue was exactly as you described, ignition on and away went the problem! Many thanx for your help!