1978 thunderbolt 1400 tach wiring(sorry...guys)

[Jenason]

I am beating this to death i know but i just read on other posts that the brown signal wire from my switchbox should be probably be switched over to where the yellow wire hooks to my rectifier in order to make my tach work on my 1997 bayliner. Read the old style hook up wont work which it doesnt..
Does that sound correct?
Just dont want to try for fear of cooking something.
Thanks again

 

[wired247]

Re: 1978 thunderbolt 1400 tach wiring(sorry...guys)

Just hook the tach signal wire to either of the rectifier yellows. Do not hook the switchbox to the rectifier. I thought we went over this already.

 

[Jenason]

Re: 1978 thunderbolt 1400 tach wiring(sorry...guys)

We did
Slow learner

 

[Jenason]

Re: 1978 thunderbolt 1400 tach wiring(sorry...guys)

Wired247..
Thank you.
I had to run a signal wire as I could not find any continuity with the existing brown(was already hooked up to the rectifier) probably not hooked into control box. Either way, she runs like a champ, on pole 6 she seems to idle at 750, seems off and at pole 3 around 1200, I'll have he out tomorrow to see which one is closest
Again
Thank you

 

[wired247]

Re: 1978 thunderbolt 1400 tach wiring(sorry...guys)

Yeah, mine was the same way. Brown wire inside the cowling was hooked up but the harness to the controls had no tach wire at all.

Wired247..
Thank you.
I had to run a signal wire as I could not find any continuity with the existing brown(was already hooked up to the rectifier) probably not hooked into control box. Either way, she runs like a champ, on pole 6 she seems to idle at 750, seems off and at pole 3 around 1200, I'll have he out tomorrow to see which one is closest
Again
Thank you

 

[Chris1956]

Re: 1978 thunderbolt 1400 tach wiring(sorry...guys)

Pole 6 is correct for Mercs..... 750 RPM is a very good idle speed.