2004 420 Sedan Bridge with Cummins...

[aliaschuck]

2004 420 Sedan Bridge with Cummins CTA6 diesels.  My fuel gauges are off by as much as 50%... I have two 175 tanks, and at 1/2 full which would be about 88 gallons to max, I am only able to put in 40 gallons til overflow.  At end of season with gauges reading 1/4 full, I added 75 gallons, and now gauges read 100% full.  This does not make sense.  While i am comfortable doing fuel runs to check my usage (a pain in the neck), I would like to replace my gauge senders at tank if this is a problem.  Anyone else have this issue? If so, how to fix?  Senders at tank?  New gauges at helm?  

[fwebster]

The easiest way to check the fuel gauge system is to remove the wire going to the center of the sender and touch the tank ground with it. The fuel gauge on the dash will jump to past full if the gauge an wiring is good.

In the mid-2000's sea Ray used some sonic senders which were prone to failure. Besides that propensity, regular swinging arm senders can fail after a few years. With the symptoms you describe, you most likely need to replace your senders.

Contact Florida Marine Tanks (who built your tanks)and ask if there is a floating puck syle sender available for your tanks. If not then order the floating arm style sender.

[Capt__Pete]

I have a similar situation on my 2003 Sedan Bridge 400. I figured the empty reading leaves a very large reserve.

[Riposo]

Are you sure you have two 175 gallon tanks? I have a 2004 420 DA and I'm pretty sure I have two 125 gallon tanks for a total of 250 gallons

[aliaschuck]

fairly certain--its on the spec sheet and confirmed by the surveyor.

[Riposo]

Interesting. I'm away from my computer but am going to check my specs and survey tomorrow - maybe I've been wrong about mine all along. Seems odd that Sea Ray would put different size tanks in the same model boat.

[Captain_Rick1]

Back to your problem. Do you have Vessel View or SmartCraft display(s). What engines?

[aliaschuck]

6CTA's not the CE version. I am going to replace senders as they only cost 85$ from Florida Marine Tanks.

[Captain_Rick1]

Have you checked and cleaned the grounding bond on the sensors? Pretty rare for a set to go bad at once. Let the Forum know what you did to fix the issue.

[Capt__Pete]

I have a 2003 400 Sedan Bridge. I got fuel this afternoon. The gauges read pretty close to empty. The starboard tank took 130 gal & the port took 120. The tanks hold 175 just like yours. I think there is about a 50 gal,. reserve on each side. It works for me., You might consider leaving your system as it is.

[Peteatthebeach]

I installed new Flexi-Sensors from Royce Industries, Inc (www.royceinc.com) in my 2003 390 MY 150 Gal tanks. the site gives you the info to select the correct depth/length of the sender. It cured my fuel quantity problems. I agree with Captain Rick also. With the new senders my gages and totalizers are right on the money for quantity

[Captain_Rick1]

Peteatthebeach. How did you calibrate the Royce senders; Are they 2 wire or 3 (I have 3 wire SSI sensors now). Appreciate your help!

[Peteatthebeach]

I calibrated it using the smart raft system onboard. The senders I installed have two wires.

[Captain_Rick1]

Thanks much. Contacted Royce and have a pair on the way.

[Captain_Rick1]

Installed Royce sensors. Works like a champ! On my 3 wire setup...you do not need the purple wire as stated earlier.