87 Chris Craft Fuel Gauge not working

[clattin]

I have an 87 Chris Craft Scorpion 196 BR that the fuel gauge has stopped working. Last summer it would work for a while and then stop working.....seems like an electrical issue as I would watch it immediately drop to empty and then later pop back up to whatever the actual fuel level was. Got the boat out yesterday and its just staying on empty although I know there is a significant amount of fuel in the tank. I've checked the connections going to the gauge and they all seem tight and I don't see any obvious wiring issues.

Thoughts? How do I troubleshoot this problem? I assume there is some float in the tank itself that sends the signal to the gauge. Could that be the problem?

Chris

 

[mjf55]

clattin, first I would make sure that all electrical connections are clean and corrosion free. This is for the gauge and the sending unit in the tank. Make sure that you are getting 12 volts at the gauge when the ignition is on. Then check it at the back of the gauge with a digital volt meter set to resistance. Check it when you need gas, then check it after you get more gas. If it changes, its you gauge. If it does not change, replace the sending unit
Hope this helps
Be careful of gas fumes and sparks.

 

[clattin]

So, it appears to be the fuel sending unit is the culprit. I have an access panel in the floor but it looks like it could be tough to pull it out through there. Also, how do I know which depth fuel tank I have? I see the fuel sending units are based on the depth of the fuel tank.

Thanks!
Chris

 

[mjf55]

The only way I can think of is the old fashioned 'pull it out and measure'.
FIRST- disconnect the ground from the battery............ ( dont want any sparks. )
Now, open the access hole/panel and remove the electrical connectors, mark which is signal, which is ground)
Clean away dirt and debris.
Now remove the sensor and measure.
Clean the gasket and everything around it
Re-install ( use new gasket if it looks bad or is cracked, worn, etc )

Other wise, you may try to figure out the height by seeing how high the top of the tank is and compare to the bottom of the boat. That would be the approximate height of the tank.

Clattin, found this link here in iBoats, may be a similar size tank http://forums.iboats.com/forum/boat...orpion-168-replacement-fuel-tank#post10075391