dash bezel apart...where to set fuel gauge needle?

[67cst]

hey guys, im going to be taking my gauge cluster apart to put a new bezel on, a year ago i had it apart to paint the needles and i moved the fuel gauge accidentally...i havent had it hooked up to the tank since then but what i want to know is will it automatically set itself when i have it hooked up to the tank and the truck is on? or do i need to fill my tank right up and aim the needle to full before i re assemble the cluster? this is probably a stupid question but ive never had to do this before and i want to get it right the first time, i hate taking these things out and putting them back in

thanks, DEREK

[JimKshortstep4x4]

If you did not remove the needle, then it will be fine.

Jim

[67cst]

i did though!! dooh, i wanted to paint them and didnt know the slitting the paper trick....so do i have to fill the tank up and then set the needle to full?

[Longhorn Man]

Yup...onless you might remember how much gas you had in it.

[whitesswj]

You can take the nedles off?
How do you put them back on and take them off?
Other than the obvious: carefully

[jorgensensc]

If you use a kitchen fork (prongs) under the needle and press down gently (leverage) they will pop right off. Be careful not to bend the needle.

[67cst]

thanks andy..i have no idea how much gas is in it, iguess ill be making a trip to the gas station with several jerry cans

[JimKshortstep4x4]

If you power up your gauge and ground the brown wire that goes to the gas gauge from the tank, the gauge should read empty. If it does not adjust the needle to empty by pulling and reinstalling it. Recheck to make sure it reads empty.

Jim

[jorgensensc]

I thought fully grounded read past empty? And fully open read past full. Am I misunderstanding?

[JimKshortstep4x4]

It can vary with where the needle is set. I have always set mine so that it reads a little under empty when grounded. That way when you hit empty there is some gasoline still left. If you set it that way, it may not read completely full. The tank unit is set to go from 0 ohms, (empty) to 90 ohms, (full). With the wire disconnected you have infinity ohms so the gauge will go past full. That is why I use a grounded gauge wire for setting the needle. Gas gauges are not real precise but most of the time they work pretty good.

Jim

[67cst]

which post goes where? this is an extra gauge i have at home, the one i need to set is at my dads so i wanna just practice on this one..where does power go and where does ground go>?

[Longhorn Man]

If you ground it, the needle should go to the 9 o"clock position...way past empty.

[jorgensensc]

O.K. Heres what I just did about 3 hours ago:
I filled up my tank.Then because I knew my fuel gauge was reading wrong, (long story, 3 floats, 1 fuse, and 2 gauges later) I took the gauge cluster off the dash (4 minutes, I'm getting good at this)
First I ran a jumper wire from the left prong (as your looking at the back of the gauge) to the fuel wire going to the fuse block (from the sender).
Then I ran a jumper from the bottom lone post to a known good ground. It is important that it is known good!
Then I ran the a jumper from the right prong to a known 12 volt keyed source.
I checked what I got for a gauge reading, then I removed the needle and set the needle to full.
Next I removed the jumper from the fuel sending unit wire, and watched the needle go past full. Then I reconnected the jumper to the fuel sending unit wire and looked where the needle pointed. I removed and adjusted the needle again.
Next I took the same jumper from the fuel send. unit wire and put it to the knlown ground. On my gauge (which I thought was weird, because i could have sworn it went past empty when grounded) the gauge went to empty. Then I took the jumper wire off the ground and let the circuit be open and go past full. Then I reconnected the wire to the fuel sending unit wire and watched it go to full.
I put the dash back together and now it all works.
For the first time, every one of my gauges works at the same time: fuel, speedo, tach. oil, and amp. Yeahhhh.

Ona side note. If you see your temp gauge not working correctly, but showing some life, and your gas gauge doesn't work either, check the fuse for the instrument panel before you tear the dash and gauges apart. Don't ask me how I know this.
Hope this helps a little.