View Full Version : Fuel Gauge stuck at 1/4 tank - 1996 ProStar 190

08-05-2007, 12:41 AM
We recently had a Depth finder installed where the clock used to be next to the Fuel Gauge.
At first the fuel Gauge was going negative, now it is stuck on 1/4 tank.
I have inspected the wiring twice and found no problems.
I Ohmed out the leads going to the fuel tank today and with the power off I am getting 62 Ohms. with the power on I get 0.
I measured the current between the tank lead and ground and it measured 110ma. during this measurement the fuel gauge read FULL.

Do I need a new sounder?

If so, what would the P/N be?

I am also looking for a Service Manual for a 1996
MasterCraft ProStar 190.


Hoosier Bob
08-05-2007, 12:48 AM
I just had my sending unit go out! Similar situation. Negative or low. I pulled (very easy) and found a magnet had come loose. The magnet sends the signal. I purchased a new one from PineCrest Marine here in Indy for under $70.00 and it works fine! I used to have to shake the boat while filling to get the float to rise! Not any more!:D

Fuel Tank Sending Unit!

08-05-2007, 10:48 AM
I just had the same thing happen to my 98! I pulled the sender out, and found the magnet had come loose from the float. Used some JB weld to re-attach & it's working fine.

08-05-2007, 11:48 AM
The reformulated gas was blamed for loosening magnets and swelling the floats. There are two small Phillips screws on the bottom of the sender and you'll be able to remove the float after removing the bottom. Pay attention to where the magnets are placed in relation to the circuit board. If the magnets are loose, Super Glue works. If the float is binding on the slides, use a file with a square edge, barely thicker than the slot, to enlarge it a bit. It won't swell more than it has. Reassemble it and it should be fine.

There's no real reason to check current on this sensor and I'm not sure there are any specs on the acceptable range. If there's voltage and the sensor or wires to the gauge aren't open but the gauge doesn't deflect, it's a faulty sensor.