fuel guage goes way past full on M1009

[NMC_EXP]

Yes the sending unit ground to the top of the framerail above the left rear tire. A flashlight helps you see the sender and wires. You just can't get to the sender without removing the tank or cutting a whole in the rear floor.

The M37-B1 I used to have had an access plate in the bed over the fuel tank sending unit cover. That was real handy.

Regards

Jim

 

[bguy193]

If the needle moves down to E, it's reading correctly. This is my fourth Blazer and every single one of them went a good half inch past the F mark when filled up. And they stay there a bit. Within 100 miles after fill-up the needle will start moving toward the 1/2 mark, but it will stay pegged a couple of days. Once it makes it's way the the 1/2 full mark it heads toward E fairly quickly.

If that's what yours is doing, you have a properly functioning 73-87 fuel gauge.

Hope this helps.

I would have to agree with Timber and Mikes47jeep............ Early 70's to late 80's gm fuel gauges worked in that way, at least all of the ones that I have owned.

 

[SoldierwithaM109A3]

check also to make sure you have a good ground . Mine did that till i took it apart and cleaned the contacts of the seating where gauge fits in the dash .

 

[panama]

I would have to agree with Timber and Mikes47jeep............ Early 70's to late 80's gm fuel gauges worked in that way, at least all of the ones that I have owned.

Mine does the same as well. I just carried around a 5 gal can of fuel and let it go down to "E". It's as accurate as I could expect from a 25 year old truck! All that matters to me anyway is that "E" really means EMPTY!

 

[BIG_RED]

Mine goes a long ways past full. Also goes about 1/8 tank past empty, and still has 1/3 tank full. I watch the odometer just to be certain. My gauge isn't accurate, but it is fairly consistently inaccurate - so it doesn't bother me. I fill it when it gets to E. Usually only takes $65.. so roughly 65 quarts.. so like 16 gallons. It's got almost a 30 gallon tank usually I still have at least a hundred miles range when "empty". Which is handy, just in case.

 

[Bethelfire]

My guage is pegged to "E" and will not move. Guess I'll track down the wires from the sending unit to the guage tommorow.

 

[doghead]

Check the ground wire from the sender to ground, first.

 

[Bethelfire]

I'll do that too............many thanks!

 

[cfish]

Question, when filling these vehicles up are they full when some fuel blows out of the anti syphan tube? My gauge goes past full but seems to track accuretly to 1/2. I haven't had it below half tank yet.

 

[doghead]

Yup, when it flows out the vent tube and back into the filler, that's about it.

 

[MuleMac01]

anyone know where to get a fule sending unit would the GM deler be my best bet?

 

[shovelheadmike]

Fuel gauges normally work with a potentiometer that varies the resistance to the voltage that drives the gauge. Not reading full when it full-less.than full is.likely.bad.connections. That can most often be resolved by cleaning all of your connections. On the other hand, if the gauge reads well over full when full, that is often the sending unit. That.said, don't give.up hope and start the search for a replacement sending unit. It may be.possible to correct the.reading with a resistor. To determine if this.would fix your problem, go to Radio Shack and get a cheap 1 K-Ohm potentiometer (linear.taper-not audio taper). Put the.pot in series.with the wire between the sending unit and the gauge. With the tank full,.adjust the.pot until the fuel gauge is reading exactly on the full mark. Remove the pot from the circuit. Tavern it back to Radio Shack and have them measure the resistance of the pot as it is adjusted during your test. Now, buy a.regular 1/4 or better yet, 1/2 watt resistor.that is closest.that they have.l to the value you need. The higher wattage value is just to have a more rugged part. Install your new.fixed value resistor in series with the sending unit and fuel level gauge. Hopefully, it.will now.work almost.linear with respect.to the actual level. I'd take stick level readings as you use up the.file in the tank to see if it is working better than before. It just might work to your satisfaction. If not, you are.only out about $5. How much is a.replacement sending unit and/or.gauge. It is.worth a.try.