Mercury RPM Guage/Tilt Trim Guage/Speedometer Guage Problems

[GeorgiaMan]

I have a 05 triton with a Mercury 50 hp motor on it. I am having problems with a few guages, rpm,tilt trim,speedometer guage.When i turn the key over the RPM guage jumps a few times and when it starts it dosn't work,the tilt and trim dont do no kind of moving , it's just dead, And the speedometer guage dosn't work, it dosn't jump around or nothing when u start the motor, the guy i got it from broke the piece that hangs off the bottom of the boat but he said it didnt work before then either.I have baught a MULTIMETER to test the wires and all , Can anyone tell me where to start and , How to use the Multimeter for that problem..I've only used it to check batteries...thanks

 

[Chris1956]

Re: Mercury RPM Guage/Tilt Trim Guage/Speedometer Guage Problems

The speedo is a pressure gauge. Water enters the transom mounted pitot (the broken one) and that moves the needle. They do break from freezing with water inside or corrosion. With a broken Pitot, it will not work as well. A bit of compressed air should move the speedo needle

The trim gauge is driven by a rheostat, like a gas gauge. Look for the sender on the transom bracket, and test it with the multimeter. Set the meter to resistance X1 scale. Disconnect the wire at the sender and put the red meter lead on the sender lead and the black lead on ground. Move the sender arm and the resistance should vary.

The tach is driven by stator pulses. Ohm out the grey wire from the tach to the voltage regulator or rectifier (whichever you have). ther should be no continuity to ground and no resistance. if that checks out, check the supply of +12VDC and ground to the gauges. They usually come from the ign switch accesssory connection, via a purple wire and a black wire.

 

[GeorgiaMan]

Re: Mercury RPM Guage/Tilt Trim Guage/Speedometer Guage Problems

The speedo is a pressure gauge. Water enters the transom mounted pitot (the broken one) and that moves the needle. They do break from freezing with water inside or corrosion. With a broken Pitot, it will not work as well. A bit of compressed air should move the speedo needle

The trim gauge is driven by a rheostat, like a gas gauge. Look for the sender on the transom bracket, and test it with the multimeter. Set the meter to resistance X1 scale. Disconnect the wire at the sender and put the red meter lead on the sender lead and the black lead on ground. Move the sender arm and the resistance should vary.

The tach is driven by stator pulses. Ohm out the grey wire from the tach to the voltage regulator or rectifier (whichever you have). ther should be no continuity to ground and no resistance. if that checks out, check the supply of +12VDC and ground to the gauges. They usually come from the ign switch accesssory connection, via a purple wire and a black wire.

thanks man will try and fix the problems...

 

[GeorgiaMan]

Re: Mercury RPM Guage/Tilt Trim Guage/Speedometer Guage Problems

I have a 05 triton with a Mercury 50 hp motor on it. I am having problems with a few guages, rpm,tilt trim,speedometer guage.When i turn the key over the RPM guage jumps a few times and when it starts it dosn't work,the tilt and trim dont do no kind of moving , it's just dead, And the speedometer guage dosn't work, it dosn't jump around or nothing when u start the motor, the guy i got it from broke the piece that hangs off the bottom of the boat but he said it didnt work before then either.I have baught a MULTIMETER to test the wires and all , Can anyone tell me where to start and , How to use the Multimeter for that problem..I've only used it to check batteries...thanks

Hey Chris I have a INNOVA 3300 meter , I am sorry I am a newbie with one.. I dont see a resistance X1 reading on this one. It has ACV DCV OHM DC10A and a battery test...