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| | | | Joined: Mar 2014 Posts: 195 Shop Shark | | Shop Shark Joined: Mar 2014 Posts: 195 | Hello again.
Today I refaced and cleaned the speedometer and odometer, and also placed a new needle on te speedo. Went really well, and easy. Tested both meters by "connecting" it to my electric screwdriver and it worked.
Now to my other gauges.. Amp meter works, fuel gauges doesn't (was never connected), temp and oil press gauges are stuck on lowest point.
So my question is, if I disassemble both "pipes" that go to the temp and oil gauges, press some air through them, should that be enough to make them
Work? I don't know how the temp gauge works at all. But as far as the oil gauges goes, I guess that's the only way to make it work?
When I move the needles by hand, the mechanics behind the oil and temp gauges move as well and then the needle drops to min again. Ofcourse I'd like to repair my gauges and sensors instead of buyin new ones. Anyone help an tips would be greatly appreciated!!
Raoul
Chevrolet 3100
Year: 1951
engine: inline 6 217CI
Transmission: Manual 3-Speed.
12Volt. | | | | | Joined: Jul 2004 Posts: 5,708 'Bolter | | 'Bolter Joined: Jul 2004 Posts: 5,708 | Raoul, Sounds like you have the restoration well in hand. Regarding the "pipes" you mention, the temp gauge uses a liquid filled tube that is factory sealed so no chance of blowing anything through there. The oil pressure gauge has a line leading into the gauge that terminates in a brass bellows that is pressure affected to move the needle on the gauge. If you put air to it, the gauge should move, but too much air pressure will damage the unit..easily. If your truck runs, the best thing to do would be hook the gauges up and see what they do. If you are in doubt, you can check their accuracy with a thermometer in the radiator fill or another mechanical oil pressure gauge 'Teed' into the engine. Even a pot of water on the stove with a thermometer can check your temp gauge. I wouldn't move the needles by hand too much..you might get a surprise. Good luck with your restoration.  Stuart | | | | | Joined: Mar 2014 Posts: 195 Shop Shark | | Shop Shark Joined: Mar 2014 Posts: 195 | As I said in my first post, neither the temp or oil gauges work with the truck running.
So the only way to make the temp gauges work is by throwing it in the garbage and order a new one?
How can the tube be factory sealed if you can take it of the gauge? or is it suppose to heat the end of the tube that goes in to the gauge? I can take pictures of mine later, maybe it isnt original?
And now to the oil gauge: do you think i need a new tube from the gauge to the motor? or should I replace that gauge too?
The reason I ask here is because i want to save these gauges instead of replacing them with new one (they're so expensive with shipping costs to Sweden..)
EDIT: Maybe a stupid question: But there is no electricty required for the temp and oil gauges right? Becuase in that case.. The fuel gauge has not been wired and in use for at least 16 years.. Do these gauges take the electricity from the fuel gauge maybe?
Last edited by Raoul; 03/09/2015 7:27 AM.
Chevrolet 3100
Year: 1951
engine: inline 6 217CI
Transmission: Manual 3-Speed.
12Volt. | | | | | Joined: May 2005 Posts: 8,983 Sir Searchalot | | Sir Searchalot Joined: May 2005 Posts: 8,983 | As Stuart says, IF the temp is a liquid filled type, it is sealed. Capillary tube and emersion bulb like this is NOT repairable. Throw in garbage if you don't want to test in hot water first. No voltage necessary unless you have an electric gauge/sender.
Oil pressure: Not permanently sealed, Partially undo connection at sender to see oil coming out, if so, problem is further up the line or... Undo connection at gauge to see oil pressure there (motor running) if not, Clean out tube or replace tube. If pressure there, gauge may be defective or just stuck with gunk and age. If no luck, throw in garbage and replace with aftermarket. No voltage necessary unless you have an electric gauge/sender.
I recommend replacing both with electric. Leave the gauges in dash/cluster for looks, hide electric under dash or modify new gauge face to match original look and place in cluster.
Right is right, even if everyone is against it, and wrong is wrong, even if everyone is for it. - William Penn
| | | | | Joined: Mar 2014 Posts: 195 Shop Shark | | Shop Shark Joined: Mar 2014 Posts: 195 | Thanks, very helpful! I'll be testing after work today!
Chevrolet 3100
Year: 1951
engine: inline 6 217CI
Transmission: Manual 3-Speed.
12Volt. | | | | | Joined: Aug 2009 Posts: 311 'Bolter | | 'Bolter Joined: Aug 2009 Posts: 311 | I sent my original '48 Temp gauge to Jim Carter with a note asking them to not clean or replace the gauge face just the capillary tube. Less then a month later I received my gauge back looking just like I sent it, and functioning like new! I believe it cost me about $125. You can see the gauge in this picture. Curt
Last edited by 801curt; 03/09/2015 5:19 PM.
| | | | | Joined: May 2005 Posts: 8,983 Sir Searchalot | | Sir Searchalot Joined: May 2005 Posts: 8,983 | Well I guess they ARE repairable. There you go, if want to pay $125 plus ship both ways to Sweden. Jim Carter is a very reputable Guy. Good info from Curt.
Right is right, even if everyone is against it, and wrong is wrong, even if everyone is for it. - William Penn
| | | | | Joined: Mar 2002 Posts: 9,115 'Bolter | | 'Bolter Joined: Mar 2002 Posts: 9,115 | I have seen an oil gauge fail to move because of a blockage right at block fitting. My heart almost stopped because it was after a friend put the engine together. | | | | | Joined: Mar 2014 Posts: 195 Shop Shark | | Shop Shark Joined: Mar 2014 Posts: 195 | Thanks for the answers, but i guess it'll be cheaper to just buy a new temp gauge. I refaced the gauges, and noticed that the needle on oil gauge was pressed all the way to the plate, so hopefully thats the only reason why it didn't work. The temp gauge tube is broken, so now i know why that one doesn't work. Now i need to rewire the fuel gauge-fuelsender , but i thought it was supposed to be wires like this: 12V source - 6V resistor - Fuel Gauge IN Fuel Gauge OUT - Fuel Sender Unit. And then the fuel sender unit would be grounded. But now i saw that there are to connectors on the unit. I guess one (outer) is for ground and the other (center) is for to connect to the gauge? picture of senderthe wires that are connected don't go anywhere.
Chevrolet 3100
Year: 1951
engine: inline 6 217CI
Transmission: Manual 3-Speed.
12Volt. | | | | | Joined: May 2005 Posts: 8,983 Sir Searchalot | | Sir Searchalot Joined: May 2005 Posts: 8,983 | Gus, can you post that diagram that Denny posted on another Gas gauge post? That picture that came from the GMC Jolly site. That would help the poster here and you are good at saving/posting info. If DG see's this, maybe he will post. A great diagram. Raoul: your sender connections, as you know, are way rusted. The gas gauge gives many people problems. The sender is available I believe ($30). Many gas gauge problems are the wiring, especially ground.
Right is right, even if everyone is against it, and wrong is wrong, even if everyone is for it. - William Penn
| | | | | Joined: May 2005 Posts: 8,983 Sir Searchalot | | Sir Searchalot Joined: May 2005 Posts: 8,983 | But now i saw that there are to connectors on the unit. I guess one (outer) is for ground and the other (center) is for to connect to the gauge? YES
Right is right, even if everyone is against it, and wrong is wrong, even if everyone is for it. - William Penn
| | | | | Joined: Jan 2010 Posts: 4,263 Shop Shark | | Shop Shark Joined: Jan 2010 Posts: 4,263 | Seems like a question about the fuel gauge comes up about once a week. I believe even a fifth grade student could understand the workings from this drawing that is circulating on the internet: http://www.pbase.com/dennygraham/image/159356931 You’re working with a basic series/parallel circuit in which the current runs thru the first winding (load) then splits into two legs for the current to flow to ground. One is thru the second winding in the dash gauge to ground. The other path is to the Sender winding to ground. When the wiper at the sender is in the empty position it offers no opposition to the current flow and since current follows the path of least resistance all of it will seek ground through this path and none will pass through the gauge. When the wiper at the sender is in the full position it offers a very high resistance to current flow in relation to the meter and the vast majority of the current flows through the gauge sensing coil and the needle show full. If the circuit is open between the gauge to the sender or if the sender is stuck in the full position then the gauge will read full. If the circuit is shorted between the gauge and the sender then no or very little current will flow through the Gauge sensing winding and it will read empty. That’s basically all there is to it. Denny Graham All gassed up in Sandwich, IL | | | | | Joined: May 2005 Posts: 8,983 Sir Searchalot | | Sir Searchalot Joined: May 2005 Posts: 8,983 | Gus/DADS50 has documented the whole process and trouble shooting procedure with pics and videos. He is your man on your AD. He will be glad to travel to Sweden if you pay the fare. 
Right is right, even if everyone is against it, and wrong is wrong, even if everyone is for it. - William Penn
| | | | | Joined: Mar 2014 Posts: 195 Shop Shark | | Shop Shark Joined: Mar 2014 Posts: 195 | Thanks guys, again, and as usual. I have seen the diagrams and everything before but couldn't find them when i used search. Sorry about that.. Im going to take out the sender, clean her up, and while I'm at it i'll clean everything behind the seat aswell (Found an old rusty american FORD(!) can with break fluid.. The truck is imported to Europe 1996 or something, haha!) then connect everything and see if the gauge works. Two more question though. 1. If i test the gauge without putting it back in the instrument panel, do i have to ground the gauge housing too? (thats how it looks like on the wiring diagram) Nevermind, i read DG's quote that DADS50 posted. 2. Does the gauge have to "stand up" to make it work? (is it sensitive for gravity?) Thanks a bunch guys, you are truly the best!!
Last edited by Raoul; 03/09/2015 9:51 PM.
Chevrolet 3100
Year: 1951
engine: inline 6 217CI
Transmission: Manual 3-Speed.
12Volt. | | | | | Joined: May 2005 Posts: 8,983 Sir Searchalot | | Sir Searchalot Joined: May 2005 Posts: 8,983 | Gauge not sensitive to angles but float when in tank is.
Right is right, even if everyone is against it, and wrong is wrong, even if everyone is for it. - William Penn
| | | | | Joined: Mar 2002 Posts: 9,115 'Bolter | | 'Bolter Joined: Mar 2002 Posts: 9,115 | While the sender is out it would be a good idea to check it with an ohm meter. | | | | | Joined: Mar 2014 Posts: 195 Shop Shark | | Shop Shark Joined: Mar 2014 Posts: 195 | My Ohm meter is broken.. Shifts between 40 and 180 but the sender is broken. I took the small housing apart and then connectors fell out, but the coil thing is still in place so I wonder if it's beyond repair or not but then I need a picture of a correct sender units inside so I can see how it's supposed to be, does anyone have that? Dads50 maybe? You have pictures of everything
Chevrolet 3100
Year: 1951
engine: inline 6 217CI
Transmission: Manual 3-Speed.
12Volt. | | | | | Joined: Jan 2010 Posts: 4,263 Shop Shark | | Shop Shark Joined: Jan 2010 Posts: 4,263 | I don't have an original sender Here is a picture of a replacement ...pic... How did you determine it shifts between 40 and 180? | | | | | Joined: May 2005 Posts: 8,983 Sir Searchalot | | Sir Searchalot Joined: May 2005 Posts: 8,983 | What do you mean by "connectors"? Pictures? A conductive, insulated metal strip is connected between the rheostat/coil (thru the housing) and the center terminal on the sender mounting flange. If you were to open up the housing (can), I'll bet the coil is disintegrating/rusting. New sender is needed. Jim Carter is capable of handling currency conversion and foreign shipping. He typically only charges actual shipping and no handling and is a sponsor here.
Right is right, even if everyone is against it, and wrong is wrong, even if everyone is for it. - William Penn
| | | | | Joined: Mar 2014 Posts: 195 Shop Shark | | Shop Shark Joined: Mar 2014 Posts: 195 | Thanks Dads50, but thats the outside,
i do now know how it works. The ohm meter i've got shifts between 40 and 180 even if i don't connect it to anything so i can't measure anything with it.
I opened the housing, the coil was intact, and works. The metal strip that goes from the mount to the housing is gone, the linkage inside the sender is totally broken and cracked, so tried to solder some stuff together but now its not reliable. So i'm going to buy a new sender i guess.
Last edited by Raoul; 03/10/2015 9:34 PM.
Chevrolet 3100
Year: 1951
engine: inline 6 217CI
Transmission: Manual 3-Speed.
12Volt. | | | | | Joined: May 2005 Posts: 8,983 Sir Searchalot | | Sir Searchalot Joined: May 2005 Posts: 8,983 | There is a spring foot wiper that wipes across the curved coil operated by the float arm. As you know.
Right is right, even if everyone is against it, and wrong is wrong, even if everyone is for it. - William Penn
| | | | | Joined: Dec 2013 Posts: 178 Shop Shark | | Shop Shark Joined: Dec 2013 Posts: 178 | While we are on gauges.....anyone find a good cheap source for the gasket (o-ring?) that goes between the glass/bezel? they should be cheaper than the ones I saw at a typical resto supplier.
Have you ever noticed that anyone driving slower than you is an idiot and anyone driving faster than you is a maniac? - George Carlin
| | | | | Joined: Mar 2014 Posts: 195 Shop Shark | | Shop Shark Joined: Mar 2014 Posts: 195 | Yes bartamos I assumed it would have been a spring loaded contact point that wipes the coil. Even though it was very much broken.
I mailed Jim carter about shipping costs so ill buy a new aftermarket iff the shipping isn't too high.
Marko, here in my town in Sweden we can buy rubber in different dimensions and cut it at disirable length for almost no money at all. Then you can make your own o-ring with some glue. Maybe that's an option if you want to get it cheap?
Chevrolet 3100
Year: 1951
engine: inline 6 217CI
Transmission: Manual 3-Speed.
12Volt. | | | | | Joined: Mar 2002 Posts: 9,115 'Bolter | | 'Bolter Joined: Mar 2002 Posts: 9,115 | Where I live, I can buy a useful volt/ohm meter for less than $10. It doesn't have to be expensive for this type of application.
| | | | | Joined: Dec 2013 Posts: 178 Shop Shark | | Shop Shark Joined: Dec 2013 Posts: 178 | Like it Raoul, I had'nt thought of that.
Have you ever noticed that anyone driving slower than you is an idiot and anyone driving faster than you is a maniac? - George Carlin
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