• Mustang Forums
  • 1965 - 1973 Classic Mustangs -General/Talk-
  • Classic Mustang Specific Tech

Adjusting Fuel gauge

  • Thread starter Thread starter KramNation
  • Start date Start date May 2, 2005
K

KramNation

New Member
May 2, 2005
6
0
0
May 2, 2005
#1
  • May 2, 2005
  • #1
Hello all,

I have a 65 mustang I'm repaing. I have replaced the sending unit, but my gauge only moves to under a 1/4 on the gauge when I fill up. I could could bend the float on the sending unit to adjust it, but how about adjusting/Replacing the constant voltage? Also, the temp gauge goes off the voltage unit too and it does not read either. I was going to by a new temp sending unit, but maybe the consatnt voltage is the problem.

Questions are:
What is the correct voltage for the constant voltage unit?
Can it be adjusted?
Would this cause it to read just a little, or would it be it either works or not works?
Is adjusting the float on the sending unit the way to adjust.

Thanks for any help.
 
M

my66coupe

Founding Member
Apr 30, 2002
1,134
0
36
Arizona fountain hills
May 2, 2005
#2
  • May 2, 2005
  • #2
Im not 100% positive on voltage but I think its around 6 for the guages. The constant voltage regulator would throw it off for sure. If the sending units are bad then yes it can as well throw the reading off.Normally if the sending units are bad, you wont get any reading at all. Pop your wires off at the sending units, and ground the wire. if your guage pegs (to the right), then the wiring is good and your sending unit is bad. Make sure your ground strap from the firewall to your engine is attached and tight, that can throw the guages off. Good luck

Mike
 
F

ForceFed70

That's why they call it "dope"
Founding Member
Dec 6, 1999
4,818
1
69
BC Canada
May 3, 2005
#3
  • May 3, 2005
  • #3
If the voltage regulator was bad, all of your guages would be reading funny... not just the fuel guage.

My guess is that the sender/tank is not properly grounded. Try running a wire directly from a good ground to the sending unit body and see if your guage starts reading properly.
 

84convertablegt

New Member
Nov 6, 2004
589
0
0
Columbus, OH
May 4, 2005
#4
  • May 4, 2005
  • #4
also, if your connector that hook up to the sending unit is going bad or corroded or your wiring is going bad, you will gain resistance in the wire which will act like the resistor in the sending unit itself, limiting the amount of ground getting back to the gauge and that will make your reading low. i had this problem, all i had to do was replace the connector with a spade terminal and added a nut to the sender stud to make a tight positive connection. problem solved.
 
You must log in or register to reply here.

Similar threads

68 fuel gauge maxes out at half
  • connella08
  • Sep 5, 2025
  • Classic Mustang Specific Tech
Replies
10
Views
271
Classic Mustang Specific Tech Sep 8, 2025
connella08
C
4375 auto meter air/fuel gauge
  • Canadianfox
  • Jul 27, 2025
  • Digital Self-tuning Forum
Replies
0
Views
98
Digital Self-tuning Forum Jul 27, 2025
Canadianfox
C
7
1970 Mach 1 Fuel Gauge Issues
  • 70 Mach
  • Jun 13, 2024
  • Classic Mustang Specific Tech
Replies
7
Views
2K
Classic Mustang Specific Tech Sep 1, 2024
Mach1 Driver
M
C
Resolved Coolant temp gauge issue
  • csracing
  • Jun 14, 2025
  • 1979 - 1995 (Fox, SN95.0, & 2.3L) -General/Talk-
Replies
3
Views
193
1979 - 1995 (Fox, SN95.0, & 2.3L) -General/Talk- Jun 24, 2025
csracing
C
1999 Mustang GT - No Start- Need help understanding the fuel pump circuit and how it works
  • 99gtGuy
  • Nov 4, 2025
  • 1996 - 2004 SN95 Mustang -General/Talk-
Replies
1
Views
489
1996 - 2004 SN95 Mustang -General/Talk- Nov 7, 2025
04newedge-
0
Share:
Bluesky Email Share Link
  • Mustang Forums
  • 1965 - 1973 Classic Mustangs -General/Talk-
  • Classic Mustang Specific Tech
Menu
Log in

Register

  • Forums
  • What's new
  • Media
  • Resources
  • Contact
  • Sponsor
X

Privacy & Transparency

We use cookies and similar technologies for the following purposes:

  • Personalized ads and content
  • Content measurement and audience insights

Do you accept cookies and these technologies?

X

Privacy & Transparency

We use cookies and similar technologies for the following purposes:

  • Personalized ads and content
  • Content measurement and audience insights

Do you accept cookies and these technologies?