sending unit? idk

[kolton]

hey guys. still waiting on the transmission fund to grow so i can get back on the road. but while it is sitting ive been upgrading, cleaning everything.

ive always wondered why it only takes 20 bucks (8/9 gallons) to fill my gas tank when it is obviously not an 8 gallon tank. never really complained about it cuz i was getting decent milage and 20 bucks seemed alot better than 40.

but now that its sitting i figured i would try and fix the problem. im thinking the sending unit is bad, or the float is broken (or sunk).
when i fill the tank the pin goes past the full mark on the gauge (a good cm)
and i always refill the tank at 1/4 tank. i dont remember how many miles i was getting on the "full" tank, but it was decent.

any suggestions? anyone else have this problem?
all help or info is appreciated.

-1987 Bii 4x4, 2.9L,D28 w/3.45's, 8.8 w/ 3.73's, M5OD (soon to come), on 33's w/8in lift


thanks guys
kolton

 

[martin]

The value of the sending units was changed at some point during the production of rbv's. If memory serves correctly the earlier units were 150 ohms and the later ones were 75 ohms. If you have an older gauge with a newer sending unit then that would answer the mystery.

 

[master hec0]

the sending unit shouldn't stop you from filling the tank unless you just put 20$ in and it shows full. just go to the gas pump and ask the jockey to fill it up pumps automatically stop when full. so if it is more then 20$ of fuel your sending unit is bad or the less likely thing someone might have divides the tank in half to hide stuff in. i have see pics of people checking there tank only to find it had been modified to hide stuff in. only guy found a couple 100 dollars worth of cigarettes in the other half of his tank.

 

[kolton]

well yeah, the pump stops at 20 bucks, i know the tank is full.

i think Martin is right, i looked at the gasket/ringlock on my tank lastnight and it looks like someone used an air hammer to close it up again. the teeth on the ring are all mangled and bent back.

is there any math that i can do to figure out the difference in the tank from the gauge?

thanks
kolton