Tachometer

[Dave1957]

Hey guys hope somebody can help me.
I have an 04 225 horse for stroke Yamaha I bought brand-new tack cannot get it working. I have power to it it lights up.
Is there anything I can look at underneath the cowling and test so I can find out why this thing is not working.
Is there anyway to test the green wire to see if I'm getting a signal from my ECM?

[boscoe99]

It is an F225TLRC. Not a 225 four stroke.

What tachometer by part number did you buy? Is it a Yamaha brand? If so, which type?

Is this a replacement tachometer for a similar one that has failed?

You can check the green tachometer signal lead for the presence of voltage when the motor is running.

Photos of what you have would be nice.

[rodbolt17]

Boscoe took a guess.
but in 04 there were several 225 HP engines made in two and 4 stroke.
all used an ECU generated tach signal.
you wont believe how many folks haven't a clue whats under the hood or deck.
yea I do stern drives as well.

[boscoe99]

Well, I thought it was a four stroke because:

"I have an 04 225 horse for stroke Yamaha"

[rodbolt17]

I totally understand.
for, four,fore whatevers
I spent 20 mins on the phone with a customer before I figured out he had an antique s250 carbed motor and he thought it was a four stroke 250.