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Fuel Sending unit, fuel gauge, and instrument resistances.

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Bulletproof250

Fuel Sending unit, fuel gauge, and instrument resistances.

I did, I swear did, search the forum for this information, or similar problem.

I installed a plastic tank 3 years ago, best thing ever. I also installed a send sending unit since the factory one was toast (gage did not work).
Everything looked OK with the install except, once I put the first 5-gallons of fuel in it, I knew something wasn't quite right, since the gage read near 3/4 tank. Hmmmm Oh well I battled with clogged fuel filters, and rebuilding carburetors way too much. I was so excited those days were behind me, that I wasn't that concerned with the fuel level too much.
That was years ago, and now I'd like to see how I can remedy the situation. So I started with the sender, It seems that the resistance is about 20 Ohms low, so that's easy I just added 20 Ohm resistor to the time, and sure enough the gage looked about right for what I estimated was in the tank. However....

2 other gages on the dash looked different, the oil pressure and the temperature, the oil pressure was higher than it had been before (mid-high vs Low-mid), and the Coolant temp did about the same.

Now hold on before you tell me the resistors are NOT the right way to fix the sender, understand that I agree, but I was looking to see if the sending unit I had was the issue, and it almost seems that there could be another factor in play here since the 2 other gages aso start to read in a more "middle of the road" measurement. since the factory gages are not annotated, there is no way to verify if they are reading accurately.

Is there anyone out here, that has had a similar experience, or expertise with the way the other gages should be reading during normal conditions?

Thanks,
Alex

1984 F-250 Std Cab (a.k.a. Harrison), Dana 60 Rear, Dana 44HD Front, Ratio 3.54:1, 351W, 2bbl Motorcraft 2150, 4WD NP208 Transfer Case, 4-Speed Warner T-18..
Med Desert Tan Metallic ("Tan? ..not brown?" <= from CT DMV worker upon registering)

-Teach your Kids to Fish, Hunt, or get them into Cars, and they'll never have the time or money for drugs.

ArdWrknTrk

Re: Fuel Sending unit, fuel gauge, and instrument resistances.

Administrator

This post was updated on .

If all three gauges are reading off you likely have a problem with the Instrument Cluster Voltage Regulator (ICVR) or the resistor that feeds the ICVR.

Gary has long advocated swapping this out for a solid state regulator (DE-SWADJ3) using a 9V battery connector.
This led to an epic microanalysis over on FTE.
I think he's ended up with it set at 5.4V*

You can read about it here:. http://www.garysgaragemahal.com/icvr.html

https://www.dimensionengineering.com/products/de-swadj3

Jim,
Lil'Red is a '87 F250 HD, 4.10's, 1356 4x4, Zf-5, 3G, PMGR, Saginaw PS, desmogged with a Holley 80508 and Performer intake.
Too much other stuff to mention.

ArdWrknTrk

Re: Fuel Sending unit, fuel gauge, and instrument resistances.

Administrator

You can see the resistance wire and how the ICVR feeds the cluster in this image from the 1985 EVTM.
Unfortunately, the 1984 EVTM in the above documentation is really just a placeholder. So this is the best I can do for you.

Jim,
Lil'Red is a '87 F250 HD, 4.10's, 1356 4x4, Zf-5, 3G, PMGR, Saginaw PS, desmogged with a Holley 80508 and Performer intake.
Too much other stuff to mention.

Bulletproof250

Re: Fuel Sending unit, fuel gauge, and instrument resistances.

Jim,

good Morning , Whoa you're up early!

Thanks for the quick info. When you mentioned the ETVM as a "placeholder" in the 1984's does that mean that, the "Instrument Voltage Regulator" doesn't exist in the 1984 Models? or is it just not shown as part of the schematic for those model years?

I'm currently marked it on my assignments to read Gary's post/knowledge regarding this problem.

again,

Gary Lewis

Re: Fuel Sending unit, fuel gauge, and instrument resistances.

Administrator

I know you asked Jim, but I'll answer. The "placeholder" bit is just to say that while I have the '84 EVTM I've not put it on the website. That's because for all practical purposes it is the same as the '85. And yes, there is an ICVR in your truck. It was used up through '86 and then in '87 the gauges changed so it was no longer needed.

Gary, AKA "Gary fellow": Profile

Dad's: '81 F150 Ranger XLT 4x4: Down for restomod: Full-roller "stroked 351M" w/Trick Flow heads & intake, EEC-V SEFI/E4OD/3.50 gears w/Kevlar clutches
Blue: 2015 F150 Platinum 4x4 SuperCrew wearing Blue Jeans & sporting a 3.5L EB & Max Tow
Big Blue: 1985 F250HD 4x4: 460/ZF5/3.55's, D60 w/Ox locker & 10.25 Sterling/Trutrac, Blue Top & Borgeson, & EEC-V MAF/SEFI

ArdWrknTrk

Re: Fuel Sending unit, fuel gauge, and instrument resistances.

Administrator

In reply to this post by Bulletproof250

If you look under Documentation>electrical>EVTM's> 19XX, you will see '1984' but it isn't fleshed out.
The wiring is so similar in 1985 (except for EFI in the 5.0l) that I guess Gary didn't feel it was worth scanning the whole book to have duplicate information.

There is definitely an ICVR in all Ford vehicles from '86 back to before I was born.

You have one, and it is the one thing common to those gauges, as you can see, in the diagram above.

I was hoping Gary would chime in since he has replaced both of his... while my '87 is the first year without one.

I do believe there is also a tutorial for retrofitting under the Bullnose Upgrades tab.

Jim,
Lil'Red is a '87 F250 HD, 4.10's, 1356 4x4, Zf-5, 3G, PMGR, Saginaw PS, desmogged with a Holley 80508 and Performer intake.
Too much other stuff to mention.

Gary Lewis

Re: Fuel Sending unit, fuel gauge, and instrument resistances.

Administrator

Yes, there is a tutorial: Documentation/Electrical/Instrument Cluster Voltage Regulator: http://www.garysgaragemahal.com/icvr.html. And you are right, Jim. I found that 5.4 volts put the three sets of gauges I tried right where they should be. So that's the voltage I dial in.

Gary, AKA "Gary fellow": Profile

Bulletproof250

Re: Fuel Sending unit, fuel gauge, and instrument resistances.

Thanks Jim, Thanks Gary,

1. For not razzing me too much for NOT searching-before-posting
2. For the highly detailed and understandable responses.
3. For your help keeping this Bullnose alive.

Gary Lewis

Re: Fuel Sending unit, fuel gauge, and instrument resistances.

Administrator

Alex - We have over 550 web pages, and some of those hold multiple documents, so it can be very difficult to find things. But, since I'm the librarian I usually know where put it.

So we aren't into razzing people for not searching. Nor for much of anything else, in reality.

Gary, AKA "Gary fellow": Profile

ArdWrknTrk

Re: Fuel Sending unit, fuel gauge, and instrument resistances.

Administrator

In reply to this post by Bulletproof250

We're are all here to help each other!
I'm sorry if my saying that Gary had left a place marker seemed cryptic....

Perhaps Gary, you should just remove the 1984 heading....
I'm just glad you worked your magic, and did whatever you did so that I can access them.
It helps me a lot to leave people a link or drop an image in a reply to someone's question.

Jim,
Lil'Red is a '87 F250 HD, 4.10's, 1356 4x4, Zf-5, 3G, PMGR, Saginaw PS, desmogged with a Holley 80508 and Performer intake.
Too much other stuff to mention.

Gary Lewis

Re: Fuel Sending unit, fuel gauge, and instrument resistances.

Administrator

I could delete it easily, Jim. But can we answer the question first? It was a test of what we thought of the new approach of placing a whole pdf on a page instead of breaking it up by section and having jpgs of each page.

As I see it the advantages are that it is easier for me. But we then cannot right-click, grab the link to the page's picture and put it in a post, which we seem to do a lot. Plus there's the issue of downloadability, which we've discussed.

So I think we should delete what's there. What say you?

Gary, AKA "Gary fellow": Profile

ArdWrknTrk

Re: Fuel Sending unit, fuel gauge, and instrument resistances.

Administrator

The '84 manual serves no purpose to me.
I find it challenging enough to have multiple pages open on my phone and navigate between them to compose an informative reply (like I tried for Alex this morning)

I DO want to thank you for all you put into this site, and your never ending efforts to improve and update it.

Jim,
Lil'Red is a '87 F250 HD, 4.10's, 1356 4x4, Zf-5, 3G, PMGR, Saginaw PS, desmogged with a Holley 80508 and Performer intake.
Too much other stuff to mention.

Gary Lewis

Re: Fuel Sending unit, fuel gauge, and instrument resistances.

Administrator

Thanks, Jim.

I didn't delete the '84 EVTM but just hid it. That way I can get back to it easily if needed.

Gary, AKA "Gary fellow": Profile

ArdWrknTrk

Re: Fuel Sending unit, fuel gauge, and instrument resistances.

Administrator

Probably for the best.
I just meant that it doesn't appear there and be a distraction.

Jim,
Lil'Red is a '87 F250 HD, 4.10's, 1356 4x4, Zf-5, 3G, PMGR, Saginaw PS, desmogged with a Holley 80508 and Performer intake.
Too much other stuff to mention.

delco1946

Re: Fuel Sending unit, fuel gauge, and instrument resistances.

Thought I’d share this link - Dennis Carpenter appears to have a solid state replace that is plug n play. It’s also easy to find if you search DCs website. Might be worth adding to the documentation.

https://www.dennis-carpenter.com/trucks/electrical/battery/d1az-10804-a-instr-cluster-voltage-regulat

Christopher in Portland Or. 1981 F250 Ranger XLT 4x4 trailer special 351M, and auto C6

grumpin

Re: Fuel Sending unit, fuel gauge, and instrument resistances.

Nice! Thanks for the link.

Dane
1986 F250HD SC XLT Lariat 4x4 460 C6-Sold
1992 Bronco XLT 4x4 351W E4OD
1998 GMC Sierra SLE K1500 350 4L60E
Arizona

Gary Lewis

Re: Fuel Sending unit, fuel gauge, and instrument resistances.

Administrator

In reply to this post by delco1946

That's great! Thanks.

The page at Documentation/Electrical/ICVR now says:

Gary, AKA "Gary fellow": Profile

Bulletproof250

Re: Fuel Sending unit, fuel gauge, and instrument resistances.

Thanks Gary, and team,

This is slightly long read but it needs some clarity over the PN's in the Documents section regarding fuel sending units.

So it's been a while and I recently had some time to crawl under the truck and find out why I was having such difficulty with the fuel gauge. I started to run out of fuel for the last time 1/4 mile from the house and was able to limp it in, where I parked it and it died. So, I dropped the tank to see what might be going on, and behold there was DEFINATELY fuel in the tank, I'd sat about 30-50lbs of it. I pulled the sparkly clean sending unit out and held it up to the side of the tank, where ir would be mounted, to see where the pickup tube stopper and it was an easy 4"+ away from the bottom of the tank. I had forgotten where I got that sending unit, but I knew it was not from the company that made the tank. I decided go to the parts store and get the right one. They got it in a couple of days and I brought it home, the weather delayed my install but I took it out of the box and matched up to the old one.... IDENTICAL Pickup tube. I plan to bring this one back, however I don't' know what I should be asking for.

What I know:
The tank is a 4252B from (https://www.gastankdepot.com/4252b-plastic-fuel-gas-tank-ford-pickup-19-gallon.html)

It is side mounted 19 Gallon,

The truck is a standard cab, long bed, with a single fuel tank

The sending unit that I have is a Spectra FG74A (shows that a 19 Gallon mid ship tank is the corresponding tank)

The Fuel gauge shows nearly 1/2 tank, however I have been messing with voltages trying to dial in the fuel level, but I think the level sender is the main issue

Documentation page shows the Sending unit for this truck to be a E0TZ 9275-G

This problem has left me stranded multiple times,

Please help,

ArdWrknTrk

Re: Fuel Sending unit, fuel gauge, and instrument resistances.

Administrator

I feel your pain. 😖
Earlier this year my side tank started weeping fuel.
When I went to replace it I found the pickup sock had come loose and was floating around in the bottom of the tank.
Obviously this wasn't even close to reaching the bottom of the tank but I had little alternative than to stick it back on the dip tube and reinstall the sender/pickup unit.

Long term I think my solution is to use a flat 'sock' like the Walbro 125-190 and extend my dip tube to the bottom of the tank with a length of hose cut at a diagonal so it can't make a seal.
225l an hour = 60 gallons and that is in line with the spec for a stock 460.

Jim,
Lil'Red is a '87 F250 HD, 4.10's, 1356 4x4, Zf-5, 3G, PMGR, Saginaw PS, desmogged with a Holley 80508 and Performer intake.
Too much other stuff to mention.

Gary Lewis

Re: Fuel Sending unit, fuel gauge, and instrument resistances.

Administrator

I think Jim has the right approach for extending the pickup. If you do that please take pics and let us know how it goes.

As for the part numbers, there's no way to correlate the factory numbers to the aftermarket ones. And the aftermarket ones tend to be one-size-fits-all, so the pickups don't always reach the bottom and the range on the sender doesn't map well to Full and Empty. What some people have done is to put a new, empty tank on the bench and looked in via the fill port to determine how much the pickup needs to be extended and how to bend the arm. But that's not easy nor safe with a used tank.

Gary, AKA "Gary fellow": Profile