Full tank/empty tank to calibrate smartcraft gauges?

[dbs1]

I don think the shop that installed them got them calibrated properly as nothing matches up. Boat should hold 54 gallons and after taking forever to fill it (like it has a restriction in the tank hose) it'll read 48 gallons and stay there for a few miles then drop quickly then start going back up but never get above 48 gallons and will show that after going 75 miles. Fuel used showed 16.9 gallons at the gauge and again, taking forever and the pump showed 14.3. Then it'll show remaining gallons of fuel and amount used to be 12 more gallons then the boat is rated to hold. That's on the speedo. At the same time the tach gauge readout of % used doesn't match either of those.

So...do I need to get all the fuel out and then fill up to get an accurate amount the tank holds and recalibrate for it to be accurate with all this? And how might I best do that?

And while I'm at it...how hard/easy is it to replace the black big cable sheathing from engine into boat that's torn in two from having the engine mounted too low and contacting the transom?

Thanks!

2010 Triton 21hp with merc 250 pro xs 2 stroke. 1B789815

[EuropeanAM]

There is a manual calibration method that requires the tank start at EMPTY, be filled to 10% volume and then saved as "Empty", repeating at 25%, 50%, 75% and 100% volume.

VERY SELDOM is this actually necessary.

Check your calibration and see if it's set to the DEFAULT calibration. If not, try it and save.

[dbs1]

Thanks Don, I'll try that.

How big of a job to replace that torn 3" black cable sheathing that goes from engine to boat? I'm guessing all the cable connections have to be removed to go through a new section of sheathing?

[EuropeanAM]

Have to de-rig (and re-rig) engine to replace it.

[dbs1]

Well then it'll have to be the shop when they raise the engine. I've had nightmares of the engine laying on top of me with both of us being smashed while trying that at home so...to the shop.

Thanks Don!!