Notices
1973 - 1979 F-100 & Larger F-Series Trucks Discuss the Dentsides Ford Truck
Sponsored by:
Sponsored by: Moser

Fuel Level System

Thread Tools
 
Search this Thread
 
Old Jan 21, 2017 | 02:49 AM
  #1  
BGF100's Avatar
BGF100
Thread Starter
|
Mountain Pass
Joined: Jul 2015
Posts: 182
Likes: 0
From: Queensland, Australia
Fuel Level System

Hi Guy's, I have a 78 F100 Cleveland 351 4x4.

I have read that a lot of people have problems with the original temperature and fuel level indicators on their trucks. Apparantly they were not so good when the trucks were new?

I have attached a description of the system.

My gauge was not so good. Now its gone worse.

I was thinlng about using the IVR7805 ( 5V regulator) that I already use in the truck. Only now using an electronic mA digital indication panel instead of the bimetalic gauge in the cluster.

Has anyone done something similar or is there a better way?

Thanks,
 
Attached Images  
Reply
Old Jan 21, 2017 | 06:56 AM
  #2  
Blue and White's Avatar
Blue and White
Postmaster
Joined: Nov 2011
Posts: 2,553
Likes: 10
In general, as new, I believe the fuel level and temp gauges were quite functional and useful on these trucks. The ammeter (if equipped) was not very useful... it basically showed little or no movement as current flow varied.

The biggest problem with the fuel gauge now is on the tank end. Re-pop fuel level senders often do not have the same winding and resistance characteristics as the original.

For the temp gauge, variation in readings may aggravated by age/condition of the gauge itself and variations in replacement senders.

If you could program or map your digital fuel and temp gauge unit to actual characteristics of the senders you are using, I believe you could get accurate readings.
 
Reply
Old Jan 21, 2017 | 11:25 AM
  #3  
NumberDummy's Avatar
NumberDummy
Ford Parts Specialist
Joined: Nov 2006
Posts: 88,826
Likes: 787
From: Simi Valley, CA
Club FTE Gold Member
The fuel sending unit float is made from two pieces of brass soldered together. Solder breaks down, gas seeps in, float settles to the bottom of the tank.

C0AZ-9202-B (replaced B7A-9202-A) .. Float is available from Ford and fits ALL 1957/79 FoMoCo vehicles.
 
Reply
Old Jan 28, 2017 | 04:41 PM
  #4  
BGF100's Avatar
BGF100
Thread Starter
|
Mountain Pass
Joined: Jul 2015
Posts: 182
Likes: 0
From: Queensland, Australia
Fuel Level System

Hi, does any body know what the resistance is when the level is
1. low and when it is
2. high?

This will give me an indication of what the current is at theses two levels will be. Thanks,
 
Reply
Old Jan 28, 2017 | 06:43 PM
  #5  
Blue and White's Avatar
Blue and White
Postmaster
Joined: Nov 2011
Posts: 2,553
Likes: 10
Dent gauges are (roughly) 10 ohms full and 70 ohms empty.
 
Reply
Old Feb 4, 2017 | 03:50 AM
  #6  
BGF100's Avatar
BGF100
Thread Starter
|
Mountain Pass
Joined: Jul 2015
Posts: 182
Likes: 0
From: Queensland, Australia
Fuel Level 5V legacy or safety

Hi,
thanks Blue dn White for the resistive values.

Does any body know if the 5V fuel level system was from legacy or required for safety?

Thanks,
 
Reply
Old Feb 4, 2017 | 05:58 AM
  #7  
Blue and White's Avatar
Blue and White
Postmaster
Joined: Nov 2011
Posts: 2,553
Likes: 10
It needs to be regulated to some value so readings do not vary as the vehicle electrical system voltage fluctuates. I guess 5 v is safer than 12 volts. Is it a requirement? IDK. Aftermarket gauges are powered by 12 volts... though they may have a regulator or other current limiting device built into the gauge itself.
 
Reply
Related Topics
Thread
Thread Starter
Forum
Replies
Last Post
moejr
1948 - 1956 F1, F100 & Larger F-Series Trucks
4
Feb 28, 2017 05:23 PM
2zwudz
1961 - 1966 F-100 & Larger F-Series Trucks
1
Nov 5, 2013 09:33 PM
eriklane
1980 - 1986 Bullnose F100, F150 & Larger F-Series Trucks
3
Jan 19, 2012 08:49 PM
xxshine
1987 - 1996 F150 & Larger F-Series Trucks
4
May 31, 2011 07:59 AM
usmcsniper2/7
1967 - 1972 F-100 & Larger F-Series Trucks
2
Feb 9, 2011 11:50 PM




All times are GMT -5. The time now is 10:03 PM.

story-0
Top 10 Fords at 2026 Carlisle Ford Nationals

Slideshow: Top 10 Fords at 2026 Ford Nationals

By Joe Kucinski | 2026-06-09 11:10:08


VIEW MORE
story-1
3 Best / 3 Worst Parts of Modern Ford Ownership

Based on years of owning multiple modern Ford products.

By Brett Foote | 2026-06-09 10:53:36


VIEW MORE
story-2
10 Amazing Upgrades That Solve Common Ford Truck Owner Headaches

SPONSORED: From muddy boots to rain-soaked cargo, these upgrades address some of the most common frustrations Ford truck owners face every day.

By Pouria Savadkouei | 2026-06-08 18:50:34


VIEW MORE
story-3
Every 2026 Ford Engine Explained

Here's everything you need to know about every Ford engine available for the 2026 model year.

By Brett Foote | 2026-06-05 12:58:01


VIEW MORE
story-4
10 Ugly Ford Trucks That We Still Kinda Love

Slideshow: 10 ugly Ford trucks that we still kinda love.

By Joe Kucinski | 2026-06-03 09:51:16


VIEW MORE
story-5
10 Things Every Truck Owner NEEDS (2026 Edition)

Slideshow: the best gifts for dads & grads

By Michael S. Palmer | 2026-06-03 15:43:58


VIEW MORE
story-6
Rezvani's Latest Post-Apocalyptic Monster Is a Ford F-150 Raptor Underneath

Slideshow: Called the Fortress, the 850-horsepower pickup combines Raptor underpinnings with military-inspired features, survival equipment, and a starting price of $285,000.

By Verdad Gallardo | 2026-06-03 11:38:36


VIEW MORE
story-7
Top 10 Most Expensive Ford Trucks Ever Sold on Bring a Trailer

Slideshow: 10 most expensive Ford trucks ever sold on Bring a Trailer.

By Joe Kucinski | 2026-05-27 16:24:34


VIEW MORE
story-8
2027 Ford Super Duty Buyer's Guide (Every Model, Engine, & Package)

Here's everything that has changed for the latest model year.

By Brett Foote | 2026-05-27 16:17:28


VIEW MORE
story-9
Top 10 Ford Truck Tragedies

Slideshow: Top 10 Ford truck tragedies.

By Joe Kucinski | 2026-05-18 19:34:33


VIEW MORE