40 merc tach installation

[jbert22]

Well I've burnt through 3 tiny tachs so I bought a faria 0-7k analog gauge. So how the heck does it hook up? Motor is a 3 cylinder 2 stroke manual start. Can't figure out where the signal wire from the tach hooks up to the motor?

[Fastjeff57]

You're in trouble there. Usually, one uses the alternator poles in the stator for the speed signal, but since you haven't one...

I suggest you give the Faria tech rep a call. They are EXTREMELY nice people and will gladly help you out.

Jeff

[Cajun Special]

Well I've burnt through 3 tiny tachs so I bought a faria 0-7k analog gauge. So how the heck does it hook up? Motor is a 3 cylinder 2 stroke manual start. Can't figure out where the signal wire from the tach hooks up to the motor?

Tach signal comes from the grey wire from regulator rectifier(on electric start). There's gotta be a way to read the ignition pulses on pull start surely.

[Cajun Special]

Been there done that several times with tiny crap. I mean tiny tach

[jbert22]

I hooked up a rectifier/regulator from a merc 150 and it works after hookin up the wires. So I can either buy one for my motor or install a simple regulator. At least that's what I was told on another forum. Any ideas about a simple rectifier?

[Cajun Special]

I was wonderin if u could still simply hook up a rectifier to it. If u can get ur hands on a factory rectifier those r pretty simple

[jbert22]

Well I just tried it and couldn't get it to work. Maybe I hooked it up wrong or maybe it was a bad rectifier. Got a pic of it il upload it tom. Maybe wrong kind of rectifier

[Fastjeff57]

Got a similar but different problem. Installed a new CDI stator (with their built in voltage regulator) and the tach doesn't like it. Goes nuts over 5 grand and shuts off, then comes back to read okay when I power down. Tach works fine with another motor (since tried). Sent a info request to CDI on this, but so far no answers.

Jeff