fuel sending unit issues

[KRB64]

I'm replacing the fuel sending unit as it hasn't worked since I've owned the truck.

With the sngine off and the ignition to "run" I put a test light to the hot wire at the unit. It pulsates like a blinker. Anybody have the slightest idea about why that could be or what I should start looking for first???

Also, for those of you that have swapped out the unit, how did you get the filter off the pickup tube?

Thanks,

[712edf]

If you are testing for voltage at the guage in the instrument panel, that is normal I believe. There is a 'regulator" thingy that plugs into the backside of the instrument cluster that reduces voltage for fuel/temp guage I think by pulsing....

Hook everything up under the dash as normal. Go back to your tank, disconnect the wire that runs forward to the instrument panel. Ground it to the frame, turn key ON, gauge should read FULL if everything in the dash area back to that point is working properly.

Do a search on this site. Somewhere about 2-3yrs ago we had a real good/informative thread that addressed fuel sending unit testing.

Bucky

[KRB64]

Didn't know that, thanks.

I'll see if I can find some time this weekend to mess with it again.

Was this the thread?
http://www.powerwagonadvertiser.com/...l+sending+unit

Another good one:
http://www.powerwagonadvertiser.com/...l+sending+unit

Anybody know how the filter attaches? I don't want to destroy it trying to take it off.

[712edf]

I think both of those threads will tell you what you need to know to diagnose your fuel gauge/sending unit issues.

I'm not sure about the pickup tube filter, I've never had to remove a sending unit or p/u tube.

Bucky

[KRB64]

Yep, new unit works fine. Thanks for the help,

[712edf]

for future reference

Yep, new unit works fine. Thanks for the help,

If the fuel gauge doesn't work and the temperature DOES work, then the problem usually isn't at the instrument panel area, If both are not working then the problem it usually is.

Bucky

[KRB64]

If the fuel gauge doesn't work and the temperature DOES work, then the problem usually isn't at the instrument panel area, If both are not working then the problem it usually is.

Bucky

Now that I know about the regulator thingy that makes sense. Good to know when trouble shooting. At least that tells you where to start looking.

[ddarnell]

Just curious. Where did you find a sending unit? Is it a behind the seat tank?
David

[712edf]

Just curious. Where did you find a sending unit? Is it a behind the seat tank?
David

If thats where the tank is, yes. Its inside the tank.

Bucky

[ddarnell]

Clarification: Where were you able to purchase a sending unit for a behind the seat tank?
David

[KRB64]

Ha ha! Amazing what difference a few words can make in a sentance huh?

I got mine off ebay. There were some behind the seat tank units on there too. Stuff reported to be NOS. Mine was suspect. No box, dented and cracked float and I thought I could see gasket residue. But the seller swore it was NOS from a warehouse and he replaced the float for free. The wire did look new still so maybe it was.

[712edf]

Sorry David, I misread your question!

Bucky

[KRB64]

When installing the sending unit I just used the cork seal and tightened it down. Is that sufficient or should I have used a sealant too?