OHM rating for 1981 Jeep J10 360 2bbl fuel tank sending unit to guage

[badaboom]

I am tring to get the OHM rating for a fuel tank sending unit.
Truck 1981 Jeep J10 360 V8 2 bbl carb. pretty much stock.

Fuel tank sending unit and sock were replaced in 1994.
Part as per receipt from Mile High Jeep Rebuilders Denver CO
Fuel sender 80-85 truck MHJ-5363977

What is the OHM rating for this unit. for full tank and empty tank
Need to replace fuel level guage. The factory window guage is inaccurate by 1/4 tank
95% of the time or always.

What is the rating for the trucks stock fuel sending unit?
Any information will be greatly appreciated.

[Jeep Craze]

Hey Badaboom,
I know that when the tank is full, It should be around 33 ohms of resistance. I forget what the empty portion should be. Just a question for ya(only because I went through the same thing about 6 months ago) Did you check the ground from the BODY of the sending unit to the chasis ground. It should be 0. If that would be anything other than 0 it will through your gauge off. I had a problem w/ that groud wire, so I ran one from the Ground on the battery all the way back to the body of the sending unit. NOW I know I have a good ground. Just a thought to possibly help you out! Craig

[Allen78J20]

The Haynes manual says about 110 ohms is full, 55 is half, and 1 ohm is empty. When I did mine I tested it to make sure I had a reading at all on the 200 ohm scale on the meter. I had 28.0. Tested the gauge, good, hooked the sending unit wire to the right post on the fuel gauge and wala, I had a 1/4 tank. Verified it with the mileage I had and I was at a 1/4 tank there too. Check your ground first!!! Im not sure if the years might be different on the ohm readings. If your using mileage to keep track of the fuel, verify that with the reading on the gauge AND the ohm meter to see if they all match.

[J20 project]

That's kinda weird, I have two sending units, one 76 and one 73 and both read about 0 OHMs full and 0 empty. Currntly trying to find a replacement gauge to match. J20

[J20 project]

Dang it, 0 OHMs full and 90 OHMs empty. J20

[Oso]

When I ordered mine from the dealer I found out that most model/years of vehicles were 0 Ohms empty and and my Jeep is 0 Ohms full with corresponding inversely proportionate scales.

It has been a while and which has the 0 Ohms on which end may be inaccurate but I think you get the idea. Some Jeeps are backassard and it is a real pain to find the backassard sending unit. It took the dealer 6 months to produce one. They wait and order batches to be manufactured.

But it was absolutely no problem finding a supplier of a 5 gallon gas can for when I erred in judgement, till the sender came in.

Uh... yes... a couple of times. Usually in the left hand turn lane of the busiest intersection. NEVER on a quiet street on a gentle downhill slope with wide paved shoulders. NEVER

[ June 20, 2002, 12:01 PM: Message edited by: Oso ]

[Don S]

Oso.. The can on the tailgate of my Waggie is plumbed!! See SIG PIC.. I've got a valve and I can switch tanks before the jeep slows down.. CUL..
your friend.. Kenardly B. Muchakooler..

.. PS I can pump a measured 5 gals. to a friend without removing the can..

[badaboom]

From what I have gathered so far.
It appears that the correct readings should be
OHM fuel sending unit.

73 EMPTY and 10 FULL

[KivaKid]

So, as you see, badaboom, no one really knows!! Hehe!

[ June 20, 2002, 05:05 PM: Message edited by: KivaKid ]

[KivaKid]

What is your sender reading? The voltage regulator thing behind the actual gauge can be faulty as well!!

[RamJetFSJ]

I checked mine when it was out (1980 wag) and it read 73 empty/10 full. I then installed a Autometer guage with the same 73/10 (for most fords before 1989 and most Chryslers), and it seems to be working fine. I havent been through a full tank of gass yet to be sure though. But I know the ohm readings from my sender are 73 empty/10 full.

[badaboom]

I can't tell you what the OHM reading is.
But the gauge when the tank is full displays 3/4 tank. 99% of the time.
Oil pressure gauge also flakey

Kivakid
What is the voltage regulator thing behind the actual gauge. (What part where)?

RamJetFSJ
What autometer part number did you install.
I am thinking about getting the 2 5/8" sport comp black face
How do you go about testing the OHM rate for the fuel sending unit?

I am starting to wonder about the little things like voltage regulator thing behind the actual gauge or possible switch degradation with the wiper switch or headlight switch additionally causing problems.