Tach question

[BDofMSP]

As I've been learning about tach calibration, I've noticed that some operate with a mechanical take-off & variable ratio alternator pickup and others with a magnetic pickup.

Simple question I'm sure, but how do I know which mine is?

Thanks
BD

 

[rgano]

Check your engine specs for a start. Then you verify is see if you have wires connected to the specified location. If so, you could disconnect them and start the engine to witness the effect at the tach. If no wiring is connected to the specified location, I would think you are stuck with wire-following from tach to engine.

 

[High Wire]

Do you have any electrical schematic drawings for your engines? They would show the source of the tach pulses.

 

[BDofMSP]

Thanks. All of the manuals and documentation is on the boat. I'll see it in a couple weeks I guess.

BD

 

[syjos]

Look to see if a grey wire is hooked up to the alternator. That is the tach signal wire.

 

[ranger58sb]

As I've been learning about tach calibration, I've noticed that some operate with a mechanical take-off & variable ratio alternator pickup and others with a magnetic pickup.

Simple question I'm sure, but how do I know which mine is?

Thanks
BD

I think you said you've got Cummins 450Cs? If correct, yours is magnetic

-Chris

 

[BDofMSP]

I think you said you've got Cummins 450Cs? If correct, yours is magnetic

-Chris

I do. Thanks Chris. I'll do a little research into how that all works. Good learning opportunity for me.

BD

 

[BDofMSP]

Well that was easy. Again sbmar.com comes through with good information and great pictures!

Thanks for all the tips.
BD