Author Topic: Fuel Gauge Sending Unit Question  (Read 1492 times)

eaglerock75

  • Newbie
  • *
  • Posts: 14
    • View Profile
    • Email
Fuel Gauge Sending Unit Question
« on: October 13, 2018, 05:37:18 PM »
The gasket on my fuel gauge sending unit has failed on my 49 Frazer.  I've removed the sending unit to install a new gasket.  I discovered that it has an earlier sending unit, a 47/48 part number 200468 instead of the 205507 that shows in the parts book.  It seems to work okay, so that is not the issue.  I intend to reinstall it.  However, when I was cleaning it up, I noticed gas dripping out of it from the underside.  The underside of the unit that faces down into the tank has a rounded bulge that protrudes down inside the tank.  Attached to the side of this bulge is the pivoting arm with float.  On bottom of this bulge is a small rivet head.  This rivet has a tiny bit of movement when you touch it, and it is from this rivet/hole that the gas drips from.  In other words, there is gasoline inside this lower bulge.  I know little to nothing about how these things work, but I think that inside there are electrical parts that the gasoline might be in contact with.  Seems like a recipe for disaster........ gasoline and electricity coming together?!  So here's the question.  Is it okay for gasoline to be inside the bottom bulge of this unit?????   Your expert advice is appreciated.  Thank you, Jim

Fid

  • Hero Member
  • *****
  • Posts: 3854
    • View Profile
    • Email
Re: Fuel Gauge Sending Unit Question
« Reply #1 on: October 13, 2018, 05:50:42 PM »
I'm not sure what you're refering to. Of course I'm not familiar with that sending unit. I can only tell you that the brass float on my Henry J once formed cracks and gasoline got inside it. When that happens, the float goes to the bottom of the tank and gauge reads empty all the time.  I was able to press the crack out larger with a screwdriver, dump the gasoling out and solder the hole shut with a solder iron (not a torch!) and it works fine now. I doubt that's your issue as the gauge would always show empty if it was.
1953 Henry J Corsair Deluxe
Edgar Kaiser's custom 1951 Henry J
1951 Kaiser Special
1952 Allstate Deluxe

Need your classic car radio repaired? I repair vacuum tube radios

eaglerock75

  • Newbie
  • *
  • Posts: 14
    • View Profile
    • Email
Re: Fuel Gauge Sending Unit Question
« Reply #2 on: October 13, 2018, 06:44:11 PM »
Thanks for the input Fid.  Looks like you did a great job repairing your brass float for your Henry J.  I've attached a few photos to show what I am talking about for my Frazer.  In one of the pics I am using a screw driver to point at the rivet in question.  Another pic shows it with the rivet dangling and loose.  The gasoline was dripping out from around this rivet.  The last pic shows the whole thing, including the tired old gasket.  I hope this helps clarify.  Thanks again !

DTort96646

  • Full Member
  • ***
  • Posts: 232
    • View Profile
    • Email
Re: Fuel Gauge Sending Unit Question
« Reply #3 on: October 14, 2018, 04:22:02 AM »
Yes that is normal for fuel to drip from that rivet. The bulge is actually the cover for the rheostat for the sending unit. A small amount of fuel can get into that cover from the pivot arm for the float. No current flows to the sending unit. The sending unit is only a variable resistance ground for the dash gauge. The rivet is a drain of sorts to ensure fuel drips out.

Fid

  • Hero Member
  • *****
  • Posts: 3854
    • View Profile
    • Email
Re: Fuel Gauge Sending Unit Question
« Reply #4 on: October 14, 2018, 11:34:18 AM »
After seeing the pics, that's a big help. DTort96646 nailed it for you.  No concerns with that.  By the way, that unit looks quite different than the Henry J unit so I'll keep that in mind for future inquiries.
1953 Henry J Corsair Deluxe
Edgar Kaiser's custom 1951 Henry J
1951 Kaiser Special
1952 Allstate Deluxe

Need your classic car radio repaired? I repair vacuum tube radios

eaglerock75

  • Newbie
  • *
  • Posts: 14
    • View Profile
    • Email
Re: Fuel Gauge Sending Unit Question
« Reply #5 on: October 14, 2018, 07:17:12 PM »
Thank you very very much DTort96646 for your post.  And thanks to Fid as well.  Now I can sleep easy knowing that I won't go up in smoke, that it is normal for fuel to drip from that rivet, and that it does not need to be replaced.  Thanks again !!