C2 - ampmeter dead

**Jack H.** · December 30, 2002, 10:35 PM

Big hammer.....

To check your alternator/voltage regulator combo are working do the following.

(1) Shut 'er down and put a voltmeter across the battery posts. You ought to see 11.5-12.5 VDC depending on charge state of the battery.

(2) Fire the engine and get 'er up above 700 RPM.

(3) Re-check the voltage impressed across the battery. It ought to be higher now (13-16 VDC depending on charge condition of battery) since a working alternator has to push the battery ABOVE it's native charge state to move current into the battery and re-charge it.

**Wayne W.** · December 30, 2002, 11:35 PM

Re: Big hammer.....

Without any equipment. Go out in the dark and turn the lights on, fire `er up and note the headlights. They should brighten as the RPM get up. If that dont convince you just alternatly un-plug and plug the two wire connector on the alternator with the engine running. The lights should brighten when the plug is connected.

**Donald O.** · December 30, 2002, 11:37 PM

Re: Big hammer.....

Jack,

I agree with your plan to check the alt/reg. But I would recommend taking the rpm to over 1500. On our older cars thats where the kick over starts.

Don

**TL Wright** · December 31, 2002, 04:56 PM

Re: Big hammer.....

Thanks to all. After reading this I kind of want to say duuhhh why couldn't I think of that. But it is always nice to get another opinion.
Now for that ammeter......Is it possible the needle is just frozen straight up from all the years of it not working? I didn't mention that only one side of the ammeter had voltage to it when I checked. I found the break in the wire and fixed so now both sides have voltage. But still the guage does not work. It does have continuity accross the terminals. Could the needle just be frozen and if so, can I break it loose without breaking the guage?
Thanks again.

**Gary Cederman** · December 31, 2002, 05:32 PM

Re: Big hammer.....

Confirming that there is voltage at the two leads is basically testing that the two leads are good. It has little to do with the meter itself. Also, when you confirmed that there is continuity across the leads is again, basically testing that the two leads are good. There is continuity between these two leads because the two leads are electrically connected to the same node (just at different locations). So, the point is, if the meter was out of the circuit completely, there would still be continuity and a voltage between the two leads.

The meter has three connections to it: The two leads and ground. You could have a bad ground connection.

I had the same basic problem with my meter. After taking it completely apart, I noticed that the screws that are used to electrically connect the two leads to the internal shunt wires were rusted. After cleaning everything, the meter then worked.

One other thing you could do prior to disassembling the meter is to measure the resistance between each of the three connections to the meter. You need to do this with the two leads completely disconnected from the meter. I did this before and after I fixed the meter and I have these numbers but, unfortunately they are not with me at this time. I could get them for you later if you would like to have them. This is how I found out that the rust was the problem because, the readings were very high for the before measurement.

When you make these measurements, you are not looking for exact numbers as to what I have. You just need to make sure that they are not open or shorted. Or very high or low readings. If any of the reading is very high (open) then it could be that is the cause.

Good luck.

**Jack H.** · January 1, 2003, 01:57 AM

Yes....

The meter movement is 'el cheapo' and not a low friction, high precision, jeweled bearing (neither was the price of the car originally). It IS possible for the needle to 'freeze' in its free-swing bearing based on prior mis-handling (shock, vibration, Etc.). This is a good case for sleuthing by way of 'borrowing' a known good panel meter from a local chapter member to troubleshoot. BUT, if the meter movement is really 'clamped', it's a real pain to go much further beyond a sharp rap/tap to see if you get 'lucky' in freeing it.... Then it would be a case for ye olde instrument restoration service!

**TL Wright** · January 1, 2003, 08:33 PM

Re: Big hammer.....

Hmmmm. I have to check that ground part out. I am sure I only saw the two leads. No ground wire. Where would that be located? Right at the plug or above? I will go back and look again. But I remember reading another thread where the ground was mentioned so I was kind of looking for it. That could be the problem.....

**Gary Cederman** · January 1, 2003, 10:42 PM

Re: Big hammer.....

There is a single ground wire (14 gage black/white) for the instrument cluster. It connects to a lug that is attached to one of the cluster screws For my '63, the lug is located near the three warning bulbs (Parking, High beam and headlamp). I don't think that it could be the wire or lug unless all of the cluster lights are not working also (i.e., the ground wire has many uses).

The meter is connected to the cluster via two small extruding screw posts and nuts (about a size of 4-40 screws). The screw posts are part of the meter and the internal end of one of them is connected to the internal ground wire of the meter. This area and the same basic areas of the other two leads that I was talking about in the other message is where I had the problem with the rust.

Jack could be correct about a stuck meter-movement but, personally, I would take it apart first and confirm that these areas are okay.

Good luck.

If I remember correctly, the internal ground wire of the meter is connected to only one of the screw posts. This is

**TL Wright** · January 2, 2003, 06:22 PM

Re: Big hammer.....

OK. Thanks for the advice. I guess I have to decide if the meter not working right now is worth pulling the instrument cluster. Cause that sounds like a job that will take some time.

**TL Wright** · January 3, 2003, 09:03 PM

Re: Big hammer.....

I did what you suggested. Thanks. I got a reading of 12.7 volts with the engine off and app 17.5 volts at 1500 rpm. Does that sound about right?

**Wayne W.** · January 4, 2003, 01:15 AM

Re: Big hammer.....

That sounds a bit high. 14.5 would be more like normal.

**TL Wright** · January 4, 2003, 10:51 PM

Re: Big hammer.....

I thought so as well. I may have checked it right after starting my engine and it was only the second time having it running since putting in the new alt. Anyway, igot the ammeter working. I tried what someone said on another thread. I took a 1.5 volt battery and connected jumper wires to the meter leads. Low and behold the the meter worked fine. Both directions, So I went back and started tracing wires. Sure enough, at the firewall, someone had reversed the connection on the two black wires that go to that block. Then I guess the horn would not work so they ran another new wire all the way to the horn relay from the steering column. Then they didn't know what to do with the wire that is supposed to attach at the starter sel, so they just cut it off. Once, I reversed the wires, got rid of the extra wire and attached the starter sel wire, everything is working fine.
Hey thanks to everyone. I would have never really figured it out on my own. Probably would have bought a new meter and then gone thru all the wire chasing.
Thanks again.

C2 - ampmeter dead

C2 - ampmeter dead

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