Rudder Synchronizer Gauge

[ronmar]

Please before you respond "just mark wheel where appears to be dead center", I want the system to work. Drives me crazy to have something not working as it should.
I have a 93 350 Aft Cabin with rudder synchronize gauge that is not registering. It appears the sender unit is mounted on the rudder link rod under the aft cabin bed. I see 3 red wires as part of the harness. 2 are attached to the sender. The 3rd is not attached and simply coiled and tied off. Does not appear to be a connection where it would attach and assuming just an extra. All connections on the gauge itself are connected and the light comes on with instrument lights but not registering for rudder position.
Does anyone know how I should test and or repair?

[Midnightsun]

I assume you mean rudder position indicator gauge? If so then they are quite simple. Basically a rheostat or variable resistance if you prefer. Normally only 2 wires are used at the sender. A wire from the gauge to the sender and a wire to ground. Here is a video which is pretty self explanatory.

[bud37]

I will just throw this out there , the red one could be for connection to auto pilot perhaps, dont know just spitballin ..........

[Midnightsun]

Not sure if these are set up differently on other boats but my auto pilot has its own sender similar to the gauge sender excepth it says Ray Marine on it. Bottom line is Carver installed a sender for each application on my boat from the factory.

[pepmyster]

And I believe mine is a dial style on the rudder arms which, that too needs adjusting, not showing center, just farts around all over.

[Viper]

Disconnect the sender actuator. Turn on the power, and while someone is watching at the helm, turn the actuator in both directions and have the person at the helm report if the gauge is moving. If it doesn't, quickly short both leads at the sender and see if the gauge sweeps. If it does, replace the sender. If it doesn't sweep, the possibilities are, the gauge, wiring, or circuit not getting power.

[amanphoto]

Have you cleaned the connections on the sending unit on the rudder? If sending unit is bad it can be replaced for around $200.

[Midnightsun]

Source of the post Have you cleaned the connections on the sending unit on the rudder? If sending unit is bad it can be replaced for around $200.

That's a lot of $ for a sender. This is what I bought however you would need to check the resistance type you have as this model may not be compatible with your gauge. https://www.ebay.com/itm/Singal-Station ... 0005.m1851

Actually that is not true since I bought the gauge and sender in a package. Really only did this because I wanted white gauges when I redesigned my dash and electronics. https://www.ebay.com/itm/KUS-Boat-Rudde ... SwpOxaAWGK

[amanphoto]

VDO Single position Rudder Indicator Sender was $112. from Defender (302194). Angle Gauge was $67. from Defender (305415).