I have an OMC cobra stern drive 3.0 litre what I would like to no is there a special trim gauge I have to use for this drive I put a ( Faria gauge on ) but it does not work it don't move it just stays in the up position I try to check out the sending unit the 2 wires that come out I put the meter on the ohms I put one lead (-) on one and put the other (+) on the other and the needle goes to the full reading any help would be helpfulthanks Jim
Hi Jim,Remove the gauge from the sender to take your resistance readings. The load from the gauge will give you faulty readings. At full down the sender should put out about 10 ohms, at full up it will be around 165 ohms. If you don't have these resistances, the sender is the problem. From the symptoms you are describing, the gauge is not "seeing" the sender and is pegging towards the highest resistance (open sender).While the sender is disconnected from the gauge, turn your ignition on. The gauge should be pegged at full up. Then short the sender terminal on the gauge to ground, the gauge should peg to full down. If it doesn't do this the gauge is bad.
gaugeguy check out the gauge like you said it works now for checking out the sender i open it at the motor the 2 blk. wires where it connects to the brn/white & blk. Now where the 2 blk. wires i see to pins in the connector is that where i put the meter to check the ohms