Pull tank or buy new guage?

I simply make a mental note of the mileage when I buy gas, and in 200 miles I pull into the station and get some more. Gas guages are highly over rated as a device that supplies any sort of useful information.

I am not aware of any calibration procedure for a sending unit, I always thought they either worked or they didn't. I suppose they could be prone to getting dirty and then not work correctly - but you clean them to fix this problem, you do not calibrate them.

If you decide to drop the tank, you should do it when the tank is empty. The bolts are going to be a pain in the ass, and you will get dirt in your eyes. The hoses that are connected to the tank should all be replaced. I think you should be prepared to replace the sending unit because I really don't think there is a way to calibrate it. You may be able to clean it with contact cleaner or equivelent, maybe fuel injector cleaner, but I can't imagine any adjustment beyond bending the arm that the float is mounted to. (I took a sending unit out once on my Dad's pick up truck, and the float was rotted to the point that it would fill with gas and sink, then when the tank was really empty, the float would drain so that a full tank would be indicated immediately after visiting the gas pump, and for a day or two afterwards.)

Hmmm.

The stock fuel gauge has a voltage regulator on it for it and the Temp gauge. If you feed 12 volts to the temp gauge you will have a dead one fast. It takes 5 volts.

Here are some good schematics on the system. Maybe you can play around with a resistor in the line rather than dropping the tank and bending things.

Mike

86/00 CJ7 Laredo, 33x9.5 BFG Muds, 'glass nose to tail in '00 88 Cherokee 235 BFG AT's

Allen wrote:

It's very easy to calibrate the sending unit. Mine was reading to much gas. Drop the tank, pull out the unit. See that metal arm that has the float on it? Bend it. Up for reading to high, down for reading to low. I just guessed on mine and endid up pretty accurate. Nick

Was the gauge correct before? It sounds like the sender is OEM, which should be calibrated properly. Do you notice it off, full or empty? If off on the empty end, you may be able to add a slight amount of resistance in series to adjust it.

The sender can be calibrated by bending the float arm up or down as an earlier poster said. I put a new sender in and it is noticeably off on the full end (full tank is reading about 7/8) - I would like to bend my arm down a bit.

Right, it is an OEM sender with an aftermarket gauge. It reads full then drops to empty when there is 10 gallons or more left in the tank. I'm just wondering what would be easier,..dropping the tank and bending the arm of the sender..or just spending the $ for a real OEM gauge that's matched to the sender. Allen

What size tank? Mine only holds 11 gallons. What kind of after market gauge? Does it fit in the original cluster? If so it should be closer than that. JimG