New style gauges replacing old

[boscoe99]

Thanks thanks boscoe99 we’re would I connecting the 5 volt supply to????.

The five volt power output would be connected to the orange wire to the sender. There should be an orange wire in the harness from the tachometer to the motor and also in the engine harness on the motor. What is depicted below is the engine harness side. The ground of course would need to be connected to a ground on the motor.

[jarrad sharp]

Just tested the old gauge to the trim sensor and the 5 volt is down orange wire as this is not connected in the new gauge I assume this is were I would connect the 5 volt supply..

[boscoe99]

Just tested the old gauge to the trim sensor and the 5 volt is down orange wire as this is not connected in the new gauge I assume this is were I would connect the 5 volt supply..

How many four pin connectors on the old gauge? Only tachometers I saw with the five volt reference wire used two connectors. With the single four pin connector tachometer the five volt reference was done away with. Reason being that new motors don't use a three wire sender. They all use a two wire sender that does not use five volts.

Anywhere you can provide five volts positive to the orange wire you can do so. Up at the tachometer or down at the motor. I think that I would do it up at the tachometer. Cleaner, dryer and less vibration up there for the power supply to deal with. Don't forget to add a fuse to and from the power supply. Just for a bit of caution. I am not responsible for any fires in any boats or motors.

[jarrad sharp]

Will defentley protect with a fuse .. thanks for the advice and help will post with results.. thanks again...

[rodbolt17]

wont work that way. the two wire sensor has different resistance specs than a three wire.
the two wire is a variable resistor,the three wire uses a pick off voltage between the orange and black.
if your tach has 3 dip switchs it can read two or three wire senders. however with the dash90 unit you have to modify the wireing slightly.
done it before.
are you sure your dip switchs are set correctly?
from the factory it is set up for 4 stroke,12pole and 2 wire.
the gray wire is only for tach overtemp visual, some 703 boxes wont work if the two gray wires are plugged in under the hood without modifying the wireing.
the gray wire is also attached to the pink wire, ground either one with the key on and the alarm sounds.

[ausnoelm]

Trim gauge is probably the most useless device fitted, if you don't know if your motor is up or down, or if the boat is not trimmed right, you shouldn't own a boat.

[boscoe99]

Trim gauge is probably the most useless device fitted, if you don't know if your motor is up or down, or if the boat is not trimmed right, you shouldn't own a boat.

Certainly in your opinion that is the situation.

I seem to remember that is what was said about an engine having a trim and tilt system when it first came out. Oh, and electric starter motors. And, a shift mechanism in the lower unit.

One man's useless teats are another man's play toys.

[rodbolt17]

does your tach have 3 dip switchs or two? are they set correctly?