How to check signal going to tachometer?

[dsibl]

I have a 16'x56" Southfork aluminum cc with a 1997 50hp Merc. I have a brand new tach on it and it is set right according to the Teleflex directions. My problem is that I don't believe the tach. I am running 35mph @ 4800rpms wot. The motor sounds like it is screeming. The size of my prop is 10 1/2x13p. Some people I talk to who have 40 and 50hp motors are running 15p props @ 5500-6000rpms Is there a way to check the signal coming from the motor to the tach? <br />Thanks

 

[Moody Blue]

Re: How to check signal going to tachometer?

You could take the boat to a shop and have the techs verify your tach by using a portable shop tach. Maybe offer to buy them lunch or something and they should be quite helpful.