Fuel Gauge not working

[62 Barnfind]

I did a rear tank conversion on my 62 during the second rebuild. I thought it was working right until I ran out of gas one night. I was told that the gauge was a 30 OHM not a 90 so I ordered and installed the 30 OHM gauge. No luck with the proper reading. It sits right below the half mark and moves a little when the power is on. It has power to the gauage, the sender is grounded and I have a new wire running up to the fuse box. What am I missing?

[damnyankee36]

I thought all rear tank conversions had the newer 90 ohm sender. Do you know what you have?

[lumpy63]

If you are using your original gas gauge the sender must be matched to that year GM gauge. Not a big fan of a lot of aftermarket senders, Even after closely following the directions on tank depth, arm length etc. I have always found the OEM GM parts to work better than than the aftermarket stuff. To the point of having my original senders rebuilt by my local speedo gauge shop.I realize that doesn't work with a rear tank conversion. What I usually do is , do the calculations for the sender, make the adjustments to the sender, ground the sender body to the chassis , hook up the the wire to the sender from the gauge,and with the ign. on ….operate the sender by hand ,from empty to full.please don't have raw gas in the area. You should be able to get a good Idea of the gauge reading . Don't be surprised if its not right on even after closely following the instructions.