Newer 50 HP 3-cyl Merc Tach Hookup Question

[Balzy]

I have a friend that bought a brand new 50 HP 3 cylinder Merc last year for his fish'in boat. He needs to buy a spare prop (smudged this one pretty good) and I would like to hook up a temporary tach to see what the thing is spinning before he buys another prop. Is there a place to pick up the tach signal? Is it as simple as a yellow wire on a rectifier like on our 2.5's? I don't have the motor here now so I can't look.

[Laker]

Or you could talk me into going along for the ride with my digital inductive tach...
How do you think I know how many RRRs my Scooter spings? :D :D

[Capt.Insane-o]

:eek: yer lyin' thats your back up motor!:p

[sosmerc]

Yup, grey wire coming out of voltage regulator. Hook your tach up to purple (switched positive) grey (tach sender) black (ground wire). The engine has a 12 pole, 6 pulse alternator, so set tach for same as V-6.

[Balzy]

Got it.

Hey how did you figure out that was my backup ????????????