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Discussion Starter · #1 ·
Well, I am still trying to finish installing my Painless Wiring harness that is anything but painless for me.

So, today I put power to the gauges and the temerature gauge and fuel gauge "pegged". I cut the power but the gauges stayed "pegged".

Now, what did I do wrong? I put switched 12V to what I believe to be the correct terminals and put the sending unit wires to what I believe to be the correct terminals (and a ground to the fuel gauge).

Why did the gauges "peg" and why won't they return to normal?

Final question... does anyone know where to get new gauges?


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Redrum (or Mike)
68 Corvette - 383 CI 427 HP
69 SS Chevelle being updated to Pro-Touring
97 Z-28
 

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Mike,
The sending unit wires probably didnt have a good connection somewhere, and that would cause the gauges to pin.

Which Guages are you using? Original Full Factory 68 gauges? Aftermarket gauges? I know I pinned my Autometer gauges while i was installing them, and afterwards they functioned fine. I don't know if 30+ year old guages will take that abuse though.

I would disconnect all the wires, then try to tap the needle down, hopefully then they will work. Then trace the wires, make sure they all have good connections.

Thats all the advice i can offer, I really dont know much about factory gauges. Hopefully someone else can chime in to tell you if the gauges are toast or not.

Good Luck
-Ryan

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1970 Chevelle Malibu
307 "fast as oiled snot!"
 

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Forgot to mention - on most gauges - the sender wire connection is located at the right most terminal (looking at the back of the dash). If you put 12v through there, you prob blew the gauge
sorry.
 

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Discussion Starter · #4 ·
69 SS 6000 RPM redline gauge pod....... I have the 12V to the right (drivers side) on all with a right side and at the top for the battery.

So, are you 100% sure that the 12V should be to the left (passenger side)?


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Redrum (or Mike)
68 Corvette - 383 CI 427 HP
69 SS Chevelle being updated to Pro-Touring
97 Z-28



[This message has been edited by Redrum (edited 11-30-2001).]
 

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Mike

I don’t have any experience with 69 gauges. However I believe they are pretty much the same as 70-72 gauges. The amp gauge is the only one that will return to 0 with power removed. So don’t be too concerned about them staying pegged. The gauges are pretty tough if you didn’t smell or see smoke it’s likely you haven’t damaged them. Visit Nonecks web site there you will find an informative article on 69 gauges. http://www.noneckschevelle.com/techtips1.htm photo#3 shows the correct connections for the power and sensors.

If you still have questions, don’t hesitate to ask.


[This message has been edited by Elree Colby (edited 12-01-2001).]
 

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Discussion Starter · #6 ·
I used Nonecks photo as my connection guide that is why I was questioning the side for 12V power. I still don't know why everything pegged and stayed.

I pulled the instrument panel last night and will verify all connections today and try again. The temp gauge was starting to go down, the oil pressure gauge is down and the fuel gauge looks to be starting down........ I still don't know what would cause this.

There was no smoke and the 10 amp fuse didn't "blow".

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Redrum (or Mike)
68 Corvette - 383 CI 427 HP
69 SS Chevelle being updated to Pro-Touring
97 Z-28

[This message has been edited by Redrum (edited 12-01-2001).]
 

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I'm sure no harm was done. When the fuel gauge goes over full it usually means the fuel tank meter is not grounded. Ground the pink wire to the fuel tank and turn the ignition on, the gauge should go to empty. If you feel the tank unit is properly grounded, make sure the engine is grounded to the chassis by use of those gold braided straps or something similiar. Another place to check is the instrument cluster ground, lack of this being grounded will do the same thing as a poorly grounded fuel tank meter.
 

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Discussion Starter · #8 ·
I have made progess, found a wiring discreprancy that cured some of the problems and I don't think the gauges were hurt. I still have 2 questions as I blew 3 fuses I am a tad nervous......


3)I have the fuel sending unit hooked on the passenger side terminal, a ground wire hooked to the bottom terminal and the switched 12V on the drivers side terminal.

I still am not sure the fuel gauge is connected right as the gas tank is empty. It pegs to full when I ground its sending wire and it stays there even if I break the ground. I suspect this is proper based on the way a sending unit was explained to work by a shop I called. So if this sounds right to you I think I am ok.

4) Now, I am not sure why I blew fuses and I have not yet hooked up the battery gauge. If I understand the Painless instructions I just hook up switched 12V to one side and ground the other. If this first assumption is right the problem is which terminal gets the 12V and which is grounded! Any clue?

Nonecks photo shows a brown sender wire but the "Painless" instructions show switched 12V and a Ground!?


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Redrum (or Mike)
68 Corvette - 383 CI 427 HP
69 SS Chevelle being updated to Pro-Touring
97 Z-28



[This message has been edited by Redrum (edited 12-01-2001).]
 

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Mike, sorry to worry you, when i said most gauges have the sender on the right, I was thinking of Aftermarket gauges. I rember my 70's dash to be the same, but that was a sweep gauges dash. Hopefully your guages are fine.
 

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Mike

You have the fuel gauge wired wrong. The switched 12V should connect to the passenger side, the tank sender to the driver side. This should stop the fuse blowing.

I disagree with the way Noneck has the amp gauge wired. One side should connect to the horn relay, the other side should connect to the J block next to the battery. I’m not sure if the painless harness uses the J block. If it doesn’t connect the second lead to the battery. I would put an inline 1amp fuse or a #18 fusible link on both amp gauge leads. The amp gauge is a voltmeter that measures voltage drop across the main power feed wire. When the battery lead is the most positive the gauge reads discharge. When the horn relay is the most positive (that way because of the alternator) the gauge reads charge. Hock it up turn on the headlights if it reads charge switch the leads on the amp gauge.
 

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Discussion Starter · #11 ·
Hmmmm... There is no horn relay and no J block. Painless "battey gauge" instructions just has one side to 12V switched and one side grounded to body.

If I understand you correctly, I shouldn't ground this gauge and that would explain the blown fuses.

I have a 50 amp fuse with a 10 Gauge direct feed from the battery. The other side provides 12V to the starter, a 30 amp secondary 3 circuit block in the trunk and the main 18 circuit Painless block.

The one wire alternator will have a 10 Gauge feed to the 50 amp block. I don't know which side it should go to but I believe it goes to the main battery feed side. Otherwise, there would be power even if the 50 amp fuse is blown! Right?

I am very disappointed in the instructions from Painless and have written them 10 pages so far with identifed errors in their instructions. Looks like I may need to write page 11 for the battery gauge? If talking directly to me would help....... 253-549-2320!

Well, the good news is before I started this I knew NOTHING about electrical wiring and I can actually understand most of what is said or told to me now.

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Redrum (or Mike)
68 Corvette - 383 CI 427 HP
69 SS Chevelle being updated to Pro-Touring
97 Z-28


[This message has been edited by Redrum (edited 12-01-2001).]
 

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I thought the reversed leads on the fuel gauge were blowing the fuse. It likely wasn’t. Yes if you ground one side of the amp gauge that will blow the fuse. I think the Painless instructions are for a Volt gauge not the factory Amp gauge. Connect the amp gauge to each end of the #10 feed from the battery. Use a #12 wire with an inline fuse at the battery end for one lead. For the fuse block end lead if you have an unused non switched fuse slot, use it. You can use a switched if you’re ok with the amp gauge not working with the ignition off. I can’t guarantee this will work it depends on the length of the #10 wire. The amp gauge will go full scale with about ½ volt. So if say a 40-amp draw from the battery gave ½ volt drop across the #10 feed wire it would be ideal. I’m guessing it will work satisfactorily.

Another option is to have the amp gauge converted to a volt gauge. Then wire it as per the Painless instructions. The general opinion is that a volt gauge provides a better indication of the charging system
 

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Also note: It is not unusual for a 69' to peg the temp and oil gauge at initial start up. They will drop back. This is because they temporarily get their voltage through a different source through the ignition switch while starting the car.
I realize this is not the problem you are referring to, but once you do get the wiring straightened out I don't want you to be surprised.

FastSS396Man

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Brian

69' SS396 Chevelle
L78 396/375hp
M-21 Close Ratio
Cortez Silver
10 year Resto
It's brand new again!
02' Harley FatBoy, Diamond Ice pearl.
 
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