Non working gas gauge in 6V 52 Champion

[poweroptions]

I am new here and new to Studebakers. I bought a 52 Champion in April /10. The only problem I can't seem to fix is the gas gauge. Everything works on the car as it should including all the instrument cluster gauges except the gas. I have installed from SI a new gas gauge and a new sending unit in the tank. I have power at the sending unit terminal under the trunk cover and power at the bottom stud on the gas gauge when the ignition is turned on. I have studied the electrical diagram in my Stude manual which seems to show only a wire from the ignition to the gauge and the wire from the gauge to the sending unit. When I installed the new gauge I notice I have 2 wires that connect to the bottom stud of the gauge and one wire that attaches to the top stud on the gauge. What am I missing ??? I want to get the gauge working . Maybe this is worth mentioning the defroster fan only blows on low speed, the heater works on both low and high. OK , I have 2 glitches in the car, otherwise I love this car !

[bondobilly]

If you look carefully all Studebaker guages and switches have letters stamped on the cases and the fiber board they are made of.

You willl need to check usiing a wiring diagram that the proper color wire terminates at the proper connection. Some of the markings can be like this TS GF 2X

They also can look a bit off center to the connector. Also do a search on this Forum about testing guages.

Bill G

[poweroptions]

On the fiber insulator board the bottom post/stud on the gauge was marked ING. Unless I'm color blind all the wires were beige.

[Carl Purdy]

Put a wire on one of the screws that hold the sending unit down and run it to a good ground on the frame and see if that helps. And I have had to ground the dash also.

[poweroptions]

Will do, changing that gas gauge gave me the screaming fits. I'm 6'3" and 275 with hands the size of shoe boxes. It was a bearcat, now I think the old gauge was ok but hey the new one shines brighter at night even if it still says empty all the time.

[nvonada]

What happens if you ground the wire to the sending unit? That should peg the gauge or at least cause it to move. If not try a jumper from the sending wire terminal on the gauge to a ground. That should isolate your problem. Remember even your "new" parts are over 30 years old so assume nothing!

Nathan

[Jeff_H]

Should be 2 posts on the back of the dash gauge. The one marked IGN should have a wire going to your ignition switch. That wire is probably jumpered over to the temperature gauge's IGN post as well. The other post should have a wire that runs back to the tank sender.

Take a voltmeter or 6v test light and check there is 6v relative to the dash at the IGN post when the key is on. The case of the gauge must be grounded to the dash. I think a '52 is all metal parts there so it should be grounded assuming all the screws and bolts are in and not rusted. Then, check the voltage at the other, sender post. If the wiring and ground of the sender at the tank is good and the sender is working, the voltage at that post will vary from 0 to 6v as the sender arm is moved. If the wire to the sender is broken or disconnected (open), or the sender is open circuit internally, you should get 6v at the gauge post and it does not change. If you get 6v there and it does not change, ground that post for a short time and the gauge needle should go from E to F. That tells you the gauge is working. Then, go back to the tank sender and check the terminal there for 6V. If there was 6v at one end and not the other, then you have a open in the wire from the gauge to the sender. If there is 6v at the sender wire, make sure the sender flange where its screwed to the tank is grounded to the car. Rust on the tank hangers could be your problem or the screws holding the sender in are not making a ground. You can add a ground wire from one of the screws to the body. Ground the sender wire for a moment and the gauge should again go from E to F. If all the above is OK, I think it was the sender is bad.

OK, so I reread your original post after writing this.... I can't comment on the physical position of the gauge posts since I've not worked on a '52. But, you have 6v at one of the posts (your bottom one it seems) that sounds good. You said there are 2 wires on that post. One of those probably goes to the temperature gauge and the other to the ign switch. Make sure that that bottom post is really the IGN post and not the sender post by mistake. As mentioned, they usually have IGN marked on the cardboard insulator on the gauge back. The other post will have the sender wire. So, you also said there is 6v back at the gauge. I'd suggest you ground that and see if the gauge goes to F but before doing that make sure the other end of the wire is correct on the gauge. If for some reason that sender wire was connected to the IGN wire going to the ign switch instead, you are going to smoke your wiring if you ground it.

[poweroptions]

Sending unit is grounded, I checked this morning and added an additional wire. I checked the current at the sending unit with my voltmeter it is at 6.6V. I removed the extra ground wire and the still read 6.6V. There is power at all times to the sending unit, key off or on. Turning the ignition on I have power at the bottom terminal on the gauge which is marked ING. The topmost terminal with the one wire has no current with the key off or on, it has no reference to what the top terminal is. The dash is all metal and there is no rust anywhere so grounding should all be ok. I can't get the gauge to do anything but read empty

[Jeff_H]

6v at the sender with key off does not sound normal at all...

Does the voltage at the gauge ign terminal go sway with key off? You said it was there with key on but wanted to make sure it was switched off too with the key.

My experience is with the '53-'54 gauges but I thought they are electrically the same as a '52. Maybe not?

Has the car ever been rewired? The original cloth covered wires would be pretty brittle by now.

[poweroptions]

The gauge ign terminal go off when I turn the key off. The car has not been rewired. It had been garaged and a one owner since 1960 . All of the wiring looks pretty good and I don't seem to have problems with any other electric items, ex: blinkers ,brakes, heater, overdrive. It starts very easy after sitting for a week. I too had thought it odd that current is to the sender at all time. I have the 51/52 shop manual but it really just grazes the fuel gage operations. It kinda freaks me to ground the sender wire to the car as it really sparks and there is no fuse. I have only done this for a moment as I don't want to screw something.

[poweroptions]

"screw something up"

[Jeff_H]

Grounding the sender wire should not produce a spark. The fact it does and also that there is 6v there regardless if the key is on or off is telling me that somehow that wire is HOT to the battery.

I printed out a copy of the wiring diagram for a '52 as found at: http://www.studebakerparts.com/stude...es/52-wire.jpg

Looking at that, the wiring for the gas gauge is the same as my '53 so what I was saying earlier should apply. There are 2 posts on the gauge and one is connected to the heat gauge and also goes to the ign switch. That power should go on and off with the key and it appears it does. The other post has a single wire that is supposed to go to the sender at the tank. There should be a variable voltage on that post as the sender arm is moved. But, you are saying its 0V all the time.

I also noticed in the diagram that the sender wire goes from the gauge to a "6 way" junction block. If its the same thing as a '53 has, then that part is a bakelight piece with 3 sockets on each end. I wonder if there are some wires that are swapped into the wrong holes on that? Per the wiring diagram, the other 2 signals going to that connector are for the stop lights and the tail lights. The stoplight one in particular is going to be HOT all the time as its coming off the circuit breaker for the lights. Does not go through the key. Do your stop lights work when you step on the brakes?

If the sender wire and the stop light wire going IN to that connector are swapped, then the 6v hot from the breaker is going to the sender and will be hot all the time. Likewise, the sender signal from the gauge is going to the stop light bulbs. Those are going to be low resistance compared to the gauge internal resistance and will pull those near ground so then it makes sense you are seeing 0v or therabouts at the gauge post all the time.

All those cloth wires are probably faded out but the sender wire is supposed to be black with a red strip. The wire for the stop light is supposed to be solid red. If you can find that connector (under the dash??) make sure that the correct color wires go into each end. This part is sorta triangular shaped with the 3 sockets on each end. They go straight through so that each corner socket's wires should match for color going in as coming out. The 3rd pair of wires in there are supposed to be black with brown stripe and are for the tail lights.

Right now, my suspicion is that the stop light and gas sender wires are swapped at that connector.

[poweroptions]

The stop lights work. I'll have to check tonight if the stop lights work with the key off, I really don't know that. The junction block you're speaking of, I am not to confuse with the junction block of wires that is under my hood in front of the radiator? There is this block with lots of wires bolted to various individual post on that block under the hood by the latch. I can't thank you enough for your help Jeff ! I had been wondering about the sender wire always being live. I was so lucky when I installed the new sending unit because the wire dropped out of the tape that was holding it and it sparked just as I was lowering the new sending unit in. It's a wonder I was blown away the tank was half full. YIKES that really scares me now.

[Jeff_H]

No, this is a in-line connector. Not the one at the radiator. I'd expect it to be either under the dash OR hanging in the harness by the firewall on the driver side where the harness comes out from the dash through to the engine side. Might be along the driver side fender too, but will be nearer the firewall. There is a harness running along the frame that has the taillight wires and the gas sender wire in it that comes up from under the car right at the firewall and will plug into this connector. Then the other side of the connector has the corresponding wires for those functions going off to the dash harness and to the stop light switch that should be somewhere in that area in with the brake lines.

I attached a sketch of what I recall these look like. Its about 2" long and has 3 wires stuck in each end. Make sure the wires match going in one end and out the other.

So, if the stop lights are working that is making me wonder if there is a short between the stoplight and gas sender wire.

EDIT:

OK thought about this a bit more. The sender wire was disconnected and taped up when you replaced the sender? If that sender wire at the tank is hot all the time coming off the circuit breaker or wherever the problem is, then when the sender arm is at full tank there is going to be basically near a short there to ground through the coil wire in the sender. It may well burn it out as normally the current is limited by the resistance inside the gauge.

I'd disconnect the battery and remove the wire at the sender and tape it up right now until the problem can be fixed. Not only a risk of a spark near the gas but also the sender may be damaged. Once the problem with that wire is sorted out it can be reconnected.

The wiring for these cars is definately not error proof! There is nothing to prevent miswiring of the harness either by the factory people or someone doing service work.

[poweroptions]

Jeff I'll be off work in a couple days and will get after this. When I first got the car my mechanic put in a new master cylinder. It's under the floor board. I have had to take the leads off to the stop switch and clean them because they corrode with bluish funk. Just last night I notice my brakelights weren't working again. I got under it pulled the female plugs off and sure enough blue corrosion again. Now I had cleaned them just 3 or 4 weeks ago. I'm really thinking you're on the right path and I'll get this figured out with your help. Again you've been a HUGE help, THANK YOU!