Crunch527

This just happened...it used to work fine...now it's totally pegged to the left and doesn't move.

Any ideas?

Thanks,

Frank

Frankie the Fink

First and quickest check I always do is a multimeter across the battery with the car running. If you see 13.8V to about 14.2V the alternator/regulator are prob OK and you have gauge problems; if less then you have alternator/regulator problems...and you can go from there...

Crunch527

Frankie,

Thanks for your time.

I checked at the back of the alternator and I have 13.9-14.2 ish...I bought another ammeter gauge from Zip the other day but haven't done the swap. I thought I might try connect disconnect the old ammeter gauge and connect the new ammeter gauge (loose) and see if the new gauge works....before I tear out the whole cluster...

While we are on this topic:

I have been experiencing a couple electrical anomalies: I have had symptoms that appear as though one of the bulkhead connectors (all new wiring) is not making good contact...for example, I will be driving and the whole car will go dead for a split second and then come back to life...it happened Sunday and the car lurched when it came back up as I was in the gas...tires squealed...the whole car jerked...this has happened a couple times recently and I thought it might be stumbling through the carb but its definitely going dead for a split second and coming back to life. Last night I moved it and when I went to start it, I got nothing...that was when I started checking all the connections...when I tried again it cranked as usual. I even jiggled the bulk head connectors while the car was running and I couldn't replicate the issue.

Another anomaly: when I turn the key to "on" the electric fuel pump will start for about 2 seconds and quit...when I turn the key to "off" the electric fuel pump will kick on for about 2 seconds. Its kind of bizarre...that is why I was eyeballing the ignition switch. It did this last night.

Could my ignition switch be going bad? I don't know much about the ignition switches...Could the contacts be worn out? Its original.

Cheers,

Frank

Frankie the Fink

Well -- its clearly an intermittent electrical problem...could be ignition circuitry or main circuits passing through the bulkhead. Its pretty easy for a bulkhead connector to get pushed in and not make contact. My '63 had an intermittent issue in this regard.

One way to isolate the problem is to take your next drive with the headlights on; if you have the problem and the headlights blink out its a main power connection; if they stray on it could well be ignition. Likewise, if the car won't start turn on your parking lights and see if you have main power...don't do the headlights in this case as the 'bump' when the doors come open could make the connection you are trying to isolate...

Not sure if the fuel pump issue is related or not...most do cycle when the ignition is turned on...

Bluestripe67

Frank, In your electrical anomalies description, "the whole car will go dead for a split second" is exactly what I have experienced three times this summer. I gauged it as a nano-second. It happened each time after a long period of driving, at or more than 45 min. I have not chased after this yet, but thought it could be tied to my engine kill system or my coil going bad. Now I'll look at the bulkhead connector. Dennis

Frankie the Fink

Its pretty easy to do some PM on the bulkhead connectors. Just pull them apart and look for any green corrosion, gunk, bent/pushed in pins, etc.. I took a .22 cal brass cleaning brush and scrubbed the connectors on both plugs at the firewall and inside the harness connectors (don't leave any stray strands of brass!). Followed by some spraying with electrical contact cleaner.

Then corrected some pushed in pin issues and coated things with dielectric grease and firmly reattached the connectors.

Of course, disconnect the battery before doing all this !!!!!!!

Easy Rhino

Also, looked for overheated components. Precursors to a potential fire.

JohnZ

There are two wires from the battery gauge (it's not an ammeter); one goes to the horn relay buss bar, and the other one goes to the big battery cable stud on the starter solenoid. One of those two wires has broken or has a terminal loose or pushed out in the bulkhead connector.

Crunch527

Ok. I had a loose connection on the starter last week...the wires were sparking when I would crank the car...could that condition possibly damage the battery gauge? I noticed the gauge being "out" about the same time.

Cheers,

Frank

toddalin

Actually, it seems that if one wire became disconnected or had a dirty terminal, the gauge would show "0" and not full negative. You need to complete the circuit to get movement.

It seems like to get a full negative, you would short one of the wires to ground, such as when you caused the spark.

So, yes, you may well have burnt out the gauge due to a short. Such a short could burn out the wiring and even burn down the car.

Crunch527

Man that would have sucked...all new wiring harnesses and because a starter wiring bolt works loose the car goes up in flames? Sheesh...I guess I am lucky. I have anew gauge, I may try hook it up temporarily and see if that fixes the issue.

Thanks!

Frank

Crunch527

I was just out fiddling with the old battery gauge...it still works...seems the needle is out of adjustment (I know there isn't an adjustment)...just seems weird. Oh, plenty of power getting to the switch. I also hooked up a new gauge and it works, so there is power through the wiring.

Enough for the night.

Cheers,

Frank

babbah

Both leads to the battery gauge have fusible links. Check them for continuity as well. Sounds like one side of the 2 feeds to the guage is faulty. Good luck.

Kuhn

I am trying fix my battery guage in my 67 corvette.Could someone tell me (or a photo) where the horn relay buss bar is located.
Thanks
Kuhn

JohnZ

It's in the left front corner of the engine compartment, screwed to the back side of the radiator support - see photo below. The buss bar is the part with the two fillister head screws.

65GGvert

I wonder if 427/435 and his buddy are reading this?

Kuhn

Thanks for the photo of the horn relay buss bar. Do you have a photo of the big battery cable stud on the starter solenoid (where the other wire is connected)
Thanks

65GGvert

Kuhn

Thanks for the photos ( they are very helpful )
Kuhn

Jim_C

Frank
The battery gauge measures very small voltage drop across a shunt. The shunt is the #10 wire running from the starter to the horn relay. If you had some sparking at the starter perhaps the shunt momentarily opened while the wires to the battery gauge remained connected. This would have put full 12 volts across the battery gauge. If this went on very long the gauge would surely burn out. But if it was short duration, "spark", the gauge would deflect really, really fast. The pointer would hit the limit pin and might have spun on the shaft. Perhaps you got lucky and just need to reposition the pointer.
CUL Jim