Fuel sending units

[AuroraGirl]

Great truck Doug. We did my sons while bed was off (super easy) and got it from LMC with no issues. Agree with other comments above on checking switching first.

Randy and E

if you cant access these now, I wouldnt worry, but if you still can, you should consider getting fuel injection hose clamps. sold at autozone in small packet of 2 or 4 of each size, iirc. koehler brand but the important part is so the hose isnt bitten by the clamp over time and then leak

 

[AuroraGirl]

Thanks for the response Sir Robyn,
What a frustrating weekend! We will jump under the truck again this week. We cleaned up all grounds to the frame this weekend. I did not check the resistor on the back of the gauge so we will pull the dash apart again as well. Do you know what I should be reading at the resistor? I pulled the plug from the firewall and checked that. I was getting 5/6 volts off one side but nothing on the other side of the plug. I am assuming that one side is the passenger and the other side is the driver side. There are 4 posts in the plug. We got frustrated and took off the camper shell and cleaned up the bed yesterday. Before and after.

are those continental boards

 

[Doug Long]

We ordered a new fuel tank switch and it should be here tomorrow so we are going to try that. fingers crossed!

 

[Ron Sebastian]

Just replaced my fuel pump assembly with a Delphi HP 10255 Hanger Assembly. Everything worked well, except the guage is now not working. There was a note on the instructions which I probably blew off since everything appeared to be connected. Something about attaching level sensor if detached. Everything appeared correct. The float moved freely. What did I miss?

You must be registered for see images attach

 

[SirRobyn0]

Just replaced my fuel pump assembly with a Delphi HP 10255 Hanger Assembly. Everything worked well, except the guage is now not working. There was a note on the instructions which I probably blew off since everything appeared to be connected. Something about attaching level sensor if detached. Everything appeared correct. The float moved freely. What did I miss?

You must be registered for see images attach

I assume it worked before? Well if there is some question about the level sensor it sounds like your gonna be pulling it back apart.

 

[Ron Sebastian]

Even though I paid special attention to the new ground spot, shined the hole and bolt and used a star washer, going to mess with that first.

 

[Doug Long]

Update, We changed the fuel tank switch this weekend and the fuel gauge is still not reading. So the sending units have been replaced, the tanks, and the fuel tank selector switch. It is ready to go to paint this weekend in time for Hot August Nights in Reno.

 

[Ron Sebastian]

You must be registered for see images attach

Can any one explain this troubleshooting guide. I'm confused on step one. Were is the selector valve harness on the cowl? Pictures would help this obviously handicapped individual. I'm still not sure my gas gauge works or that I am actually switching tanks.

 

[CalSgt]

Your EFI truck may be different but...

IIRC my 1980 had a plug near the throttle cable on the firewall, there was a double ended plug built into a grommet that passes through the firewall. There was a rubber harness plug on the engine side and another in the interior.

Just to the left of the brake booster at the top of this picture

You must be registered for see images attach

 

[Ron Sebastian]

"The solenoid grounds by being bolted to the frame"
Is this right on an 87 also?

 

[SirRobyn0]

"The solenoid grounds by being bolted to the frame"
Is this right on an 87 also?

Ron, Keep in mind there we two tank switching valves used, a one wire and the other one has I think 5 or 6 wires. The one wire type grounds though being bolted to the frame. The multiple wire one does not.

 

[Ron Sebastian]

Ron, Keep in mind there we two tank switching valves used, a one wire and the other one has I think 5 or 6 wires. The one wire type grounds though being bolted to the frame. The multiple wire one does not.

Sir, the individual pumps ground to the frame also. I don't think I have a ground issue, I believe it's a short. Who knows where.

 

[Plaligraphy]

When i had restored my Jimmy fuel tank ('88 with fuel pump in tank due to fuel injection) i ordered the one out of LMC. Its been working great honestly. Just ordered another for the parts truck, cheapest i could find at my local O'Reillys. Yet to see how it goes. I think it may be Spectrum brand, Autozone was doing a more expensive Delphi. So i'd suggest LMC, determine as to how many outlets you have and then order the one for your truck, assuming you obviously have a saddle tank(s)

You must be registered for see images attach

+1 for LMC, been working a treat for me for about a year now with no issues

 

[Powerhouse Ranch]

+1 for LMC, been working a treat for me for about a year now with no issues

update: LMC one still holding up, may have to pull it out though in the future and replace with one of those fancy Holley sending units if i put the Sniper on. P.O.S. one from the parts store i put in the parts Suburban still has yet to work. either i'm missing something somewhere else or this thing was junk out of the box. who knows. too busy to find out for sure.

+1 for LMC indeed. rarely do they disappoint.

 

[SirRobyn0]

Sir, the individual pumps ground to the frame also. I don't think I have a ground issue, I believe it's a short. Who knows where.

Ron I'm not trying to be difficult when I say this but I was simply answering your question which was "The solenoid grounds by being bolted to the frame. Is this correct on an 87" I gave you the answer to that nothing more.

IDK, if you have a ground issue or a power issue. The only way you will solve your problem is though continued troubleshooting. At this point I'm not really sure I can offer more suggests than what I and others have made, but I'm certainly able to answer questions that might help you troubleshoot it.

I will look over the thread again and see if I can come up with any good ideas.