Current Classifieds

free transmissions
Date: 11/28/2019 10:21 am
Wanted early pinto
Date: 10/03/2019 02:42 pm
78-80 Windshield
Date: 10/29/2021 03:11 pm
Wheels and Parts

Date: 07/06/2018 04:50 pm
72 pinto drag car

Date: 07/08/2017 08:25 pm
Looking for leaf spring insulators
Date: 04/04/2020 09:38 am
1973 Pangra gauge and tach panel

Date: 11/02/2019 10:25 am
Wanted Pinto Fiberglass Body Parts
Date: 05/19/2018 04:56 pm
Wanted 73 pinto squire wagon
Date: 05/09/2020 11:59 am
Various Pinto stuff for sale.
Date: 11/21/2018 01:56 pm
New cam

Date: 01/23/2017 05:11 pm
1971 Pinto Parting out

Date: 07/06/2018 01:11 pm

Author Topic: Gas gauge  (Read 1093 times)

0 Members and 1 Guest are viewing this topic.

Offline caravan3921

  • Pinto Full Member
  • ***
  • Posts: 235
  • FeedBack: +0/-0
  • Gender: Female
  • Another Pinto Driver

  • Total Badges: 7
    Badges: (View All)
    Mobile User Poll Voter Topic Starter Tenth year Anniversary Windows User Apple User Fifth year Anniversary
Gas gauge
« on: June 05, 2021, 12:22:43 PM »
The gas gauge appears to be acting unreliable lately.
Seems to always be stuck at 3/4 full when it should be going down.
Filled it to full yesterday and drove it home 2 blocks away and it was at 3/4.
What would the experts do?
Thanks!

Offline Wittsend

  • Pinto Master
  • *****
  • Posts: 2496
  • FeedBack: +241/-0

  • Total Badges: 8
    Badges: (View All)
    Tenth year Anniversary Mobile User Topic Starter Poll Voter 1000 Posts Linux User Windows User Fifth year Anniversary
Re: Gas gauge
« Reply #1 on: June 05, 2021, 02:54:57 PM »
Likely it is a sinking float, or there is varnish on the sender resistor. I don't know if the floats are available but it isn't too difficult to remove one (the float itself and a length of the arm it attaches too) from a junk yard car and adapt (solder) it to the existing arm. And by that I mean solder a portion of  metal arm that holds the new-er float to the existing arm, not solder the float itself  - which today is likely plastic.

Varnish can be removed often by scraping it but be careful not to damage the wound wires on the resistor.

Offline oldandcrotchety

  • Pinto Member
  • **
  • Posts: 47
  • FeedBack: +0/-0
  • Gender: Male

  • Total Badges: 5
    Badges: (View All)
    Tenth year Anniversary Topic Starter Poll Voter Windows User Fifth year Anniversary
Re: Gas gauge
« Reply #2 on: June 05, 2021, 05:10:05 PM »
I don't know if Pintos used them, but a lot of the old fords had a resistor behind the fuel gauge that would go bad.  When it does go bad, the gauge will read 3/4 tank when it is really full, and then run out of gas with the gauge showing 1/4.  I had that happen on my '64 ford pickup and also on a 1970.  They are real easy to replace, but as I said, I have no idea if were used on the Pintos.

Offline Mattb

  • Pinto Member
  • **
  • Posts: 46
  • FeedBack: +3/-0
  • Another Pinto Driver

  • Total Badges: 1
    Badges: (View All)
    Fifth year Anniversary
Re: Gas gauge
« Reply #3 on: June 05, 2021, 06:27:55 PM »
Based on the picture of you car looks like you have a 77 or a 78.  For those years in my experience the Pinto and Mustang II used the same sending units. If you go to Spectra’s website and look at their e catalogue they list sending units for the Mustang  II.  You would probably want the FG 179B( I believe that is what I used). It has a second pipe for a return line. The V8 Mustang II  did not have a return line. It appears the 179B is not available right now. The 1976 cars use a FG 178B which looks like the same dimensions but has a slightly different Ohm range( 85-10 vs75-10).  When I pulled the tank we actually put in a new tank as well along with new rubber parts. Just something to consider. Best wishes.

Offline LongTimeFordMan

  • PCCA VIP
  • Pinto Sr. Member
  • ***
  • Posts: 450
  • FeedBack: +182/-0
  • Gender: Male
  • 1973 Red Pinto Wagon

  • Total Badges: 6
    Badges: (View All)
    Fifth year Anniversary Topic Starter Signature Windows User Linux User Mobile User
Re: Gas gauge
« Reply #4 on: June 05, 2021, 08:57:01 PM »
i think the "resistor is actually a voltage regulator to regulate the instrument voltage at 6 volts.

the oem ones had a system like a turn signal flasher that turned and off. there are also new style electronic ones avaialble.

but your problem seems like it might be the sending unit.

you can also test the resistance of the sending unit.. it should range from 10 ohms full to to.70 or 80 ohms empty (see the above post ) as the level in the tank

if the.resistance of the sending unit changes with the level, the problem could be the voltage regulator.

inpostes a post about building and calibrating an electronic regulator here awhile back.
Red 1973 pinto wagon DD, SoCal desert car, Factory 4 speed, 3.40 gears, Stock engine, 14" rims and tires, 60 K original miles

Offline PintoRoyL

  • Pinto Member
  • **
  • Posts: 61
  • FeedBack: +1/-0
  • Another Pinto Driver

  • Total Badges: 3
    Badges: (View All)
    Topic Starter Mobile User Poll Voter
Re: Gas gauge
« Reply #5 on: September 19, 2021, 08:09:41 PM »
Hello,
I am about to replace the fuel tank in my '74 Runabout, I want to get a new fuel sending unit. I understand that the 178B mentioned above will also fit in a 1974 Mustang II (according to RockAuto). Do you think it will also work for the '74 Pinto? (RockAuto does not list a fuel sender for a '74 Pinto)
Thank you.

Offline Mattb

  • Pinto Member
  • **
  • Posts: 46
  • FeedBack: +3/-0
  • Another Pinto Driver

  • Total Badges: 1
    Badges: (View All)
    Fifth year Anniversary
Re: Gas gauge
« Reply #6 on: September 20, 2021, 02:04:30 PM »
Based on my experience with my 77 if the fuel tank you are using works for a 74 Mustang II then the corresponding sending unit will probably work as well. You could pull the old one out and compare to the pictures. Are you using the Spectra F80A tank?

Offline PintoRoyL

  • Pinto Member
  • **
  • Posts: 61
  • FeedBack: +1/-0
  • Another Pinto Driver

  • Total Badges: 3
    Badges: (View All)
    Topic Starter Mobile User Poll Voter
Re: Gas gauge
« Reply #7 on: September 20, 2021, 06:42:56 PM »
Does Spectra make a new tank for Pintos? I am going to use the old original, I see nothing wrong with it. When I removed the tank several weeks ago, I emptied the old "gas" that was 25 yrs old, and after everything dried out, I stuck the hose from my shop vac in to get the debris that I was unable to shake out through the fuel inlet hole. Since the sending unit mounts low in front, I went ahead and reinstalled the tank without the sending unit installed. I took a chance and have already ordered from RockAuto the Spectra FG178B unit mentioned in an earlier post. RockAuto does not list a sending unit for a '74 Pinto, but says that the FG178B will fit a '74 Mustang, so I will give that a try.

Offline Mattb

  • Pinto Member
  • **
  • Posts: 46
  • FeedBack: +3/-0
  • Another Pinto Driver

  • Total Badges: 1
    Badges: (View All)
    Fifth year Anniversary
Re: Gas gauge
« Reply #8 on: September 20, 2021, 07:57:38 PM »
Well the Spectra F80A is listed as being for the 75-76 Pinto and the 74-76 Mustang II so not sure if the 74 Pinto tank is different from the 75 or different from the 74 Mustang II tank. Sounds like you have a usable original but if issues arise could try the F80A( or have your tank restored). Let us know if the sending unit works out.