2006 x30 - ballast gauge dead

[riptide22]

Hello, one of my gauges on my ballast tanks is not working at all. The tank fills and empties but no movement on the gauge.

The dealer says it is either the gauge or sending unit.
Does anyone have an idea which way to go?

Also, where is the sending unit located? Is there a schematic for Mastercraft boats somewhere as I could not find one on the internet.

Thanks

[Skyskiguy]

Most likely the sending unit. It's in the top of the tank which, if it's one of the rear tanks, is under the carpeted trunk floor panel that attaches to the top of the tank. A couple of screws is all it takes to remove the trunk floor panel. If it's the KGB tank, pull up the floor panel that looks like a ski locker in the front walk-through.

[Skyskiguy]

Those sending units are notoriously unreliable. Many people just ignore the gauge and fill until it spits out the side overflow port and empty until it stops spitting out the side drain port.

[blackhawk]

The top of each sending unit has potentiometers that you can adjust with a screwdriver. There is one for your empty reading and one for the full reading. You can try adjusting these, but as Skyskiguy said the sending units are unreliable. I can adjust mine to be perfect, then within a couple of trips they are all out of whack again.

[riptide22]

Thanks everyone. This is very helpful

[Alistair]

Those sending units are notoriously unreliable. Many people just ignore the gauge and fill until it spits out the side overflow port and empty until it stops spitting out the side drain port.

Exactly what I do - I even removed the gauges as they were a waste of time.

The senders are so unreliable, they stopped fitting them - on newer boats, the fill level being displayed is just a reflection of how long the pump was on and is not an actual measurement of how much water is in the tank.