Fuel Gauge Reading

Club Coupe

I have a strange thing going on with my Pacemaker's fuel gauge and I can't figure it out. I'm hoping that maybe someone else has experienced this problem and has a solution. For the last three winters, once the outside temperature drops below 40 degrees, my gauge quits working. Once spring comes and the outside temperature warms up above 55 or so, it works perfectly. The car is garaged with 2 other older cars and the other 2 don't have this problem. I know that the tank is about 3/4 full because I started the car 3 days ago (when it was 60 degrees outside) the guage worked. Last night the temperature dipped into the 30's and low and behold today the gauge shows empty. I don't take the car out in the winter so this isn't a real problem, but it's starting to really bug me. The temperature in the garage was about 55 degrees when I started the car a few minutes ago. Outside was 48 degrees. The temperature gauge works fine as do all the other electricals. Does anybody have any ideas?

Park_W

What year Pacemaker?

[Deleted User]

Has the sender been checked lately? Might be some crud hardening up at colder temps.Possibly a cleaning might be in order.

[Deleted User]

Sounds like a bad connection someplace ,metal move with temperature change. And can cause things like bad ground to work loose. Try puting a jumper wire on a clean spot on the frame to the sending unit screws or the tank ,
Roger

Club Coupe

Park: It's a 1951, switched over to 12 volt.
Hudzilla: Sender was replaced about 5 years ago but I haven't pulled it for cleaning. I've been using PRI-G gas treatment faithfully in the hope of keeping the crud levels down.
Tallent: A bad ground hadn't occured to me. I figured if it worked when warm it should work when cold, but never gave any thought to expansion and contraction of metals because of temperatures. I guess I need to check the ground this weekend.

Park_W

If it doesn't turn out to be a bad ground, try this: At a time when the gauge isn't working, turn the key on, then run a little jumper from the terminal on the sender to ground. If the gauge swings over to full, you'll know everything except the sender is OK Don't keep the sender wire grounded and gauge on the peg very long ... can damage the gauge.

Marconi

Got the same problem with my 62 Buick. I think I've got it figuered out to be the guage itself, as everything checks out O.K.

[Deleted User]

What Park says is right , essentialy all the sender does is provide a ground to the gauge. So grounding the wire back at the tank OK's everything else in the circuit if the needle swings over.
That is why grounding is so crittical to proper opperation ,
Roger

Club Coupe

Thanks a bunch guys. I'll see what I can get done over the weekend and report back.

Club Coupe

Park & Roger: I got under the car and grounded the sender and sure enough the needle went towards "full" so I suppose that I have a bad sender after all. The electric fuel pump is grounded to one of the sender screws, so I am thinking that the ground is okay. I did check the electrical connection at the sender and it is tight. I noticed today that the gauge will move slightly, to about 1/8. When it comes to electrical I freely admit to being a moron, so, here's another stupid question; is there anything else other than replacing the sender that I might try? It doesn't look like I can replace it without dropping the tank, so I'll have to wait until I run some gas out of it as the drain plug is impossible to get out. Thanks for all the help.

Park_W

If it's an original type sender you can try taking the little cover off the mechanism and spraying the "wiper" and the resistor windings with contact cleaner. You may be able to bend the wiper just a little to ensure it's making good contact with the resistive windings (you'll see what these terms refer to when you open it up).

Club Coupe

Park: It's a Ford truck type replacement sender. I'll get under the car tomorrow and see if I can find the little cover and get it opened up. Anything is better than dropping the tank by myself. Thanks again.

Park_W

To clarify, the aforementioned "little cover" is accessible only with removal of the sending unit from the tank. But that's not too difficult, just a bit awkward getting at some of the screws. If needed, you can loosen the hanger straps a little so the front end of the tank drops down a little.

Club Coupe

Park: I wish that I had read your post before I crawled under the car a few minutes ago. After I gave the sender a good look I sort of realized that you ment that the "little cover" wasn't outside of the tank. Like I said, I'm an electrical moron. I think that I'll order a new sender from Paul S., run some of the gas out of the tank over the winter and have myself a nice Springtime project, changing the sender. Thanks for all the help and advise.

Marconi

If your guage "moves a little"it could be that the float on the sender has sprung a leak and has partially sunk. Replacements are nylon from a 70s or 80s Ford.

Park_W

Good point, Marconi. I've had more than one float develop a crack and sink.

Club Coupe

So . . . this afternoon I start the car and the gauge goes up to 1/2, where it was when the weather turned cool. It was close to 70 degrees today. This is just a mystery to me, why the cooler weather effects the gauge reading. It may well be a bad float, ethanol gas causing crud that effects the float, or a bad sender just like you guys have suggested . I think that I'll replace the sender in the Spring, clean up and check out the current sender and maybe have an extra on hand, depending on my success, or lack of, with the current sender. Or, perhaps I could move to a warmer climate. The car did originally come from St. Petersburg, Fla, so maybe it wants to retire to where it started out. Again, much thanks to everybody for your help.

Glowplug

Today while reseraching a fuel guage problem using the 48-54 Body Manual, I discovered a bit of information I had "glossed over" while previously reading. That bit of information is- if the subject Hudson has a radio installed a noise supression condensor"maybe" connected to the power circuit of the fuel and temp guages. Should this condensor fail to operate correctly it will in turn cause the fuel and temp guage operation to be fautlty. Interesting that this point failed to register with me in the past. Wonder how many folks have had this problem and replaced guages or power regulators?

[Deleted User]

As far as this car goes an old paper capacitor would possibly be affected by temp. & moisture.
Roger