Help with amp meter
Thread Starter
Drifting
Joined: Oct 2002
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From: ar
Help with amp meter
I am trying to make sure all my gauges are working correctly before restoring my cluster on roadster project.
What should it read after a cold start up and when the lights are on, etc?
I have ran the car 4 or 5 times the last year and have not had to charge the battery so I feel like the charging system is working fine, just need to know if the gauge is working correctly.
Thanks Jeff
What should it read after a cold start up and when the lights are on, etc?
I have ran the car 4 or 5 times the last year and have not had to charge the battery so I feel like the charging system is working fine, just need to know if the gauge is working correctly.
Thanks Jeff
Thread Starter
Drifting
Joined: Oct 2002
Posts: 1,818
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From: ar
The meter shows a little left of center and goes a little more left when I turn on the lights. I guess since the battery is getting charged, I may need to figure out how to check the gauge. Any suggestions?
Jeff
Jeff
Drifting
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From: DeBary Fl. Amateur Radio Operator K3CQR
Jeff, if the engine is running at more than idle speed, and you show no + on the meter, then it's a charging problem. Check if alt belt is tight, Check with a Multi meter on the batt contacts that you are showing at least 13.9 volts with engine running at higher than idle. Bill
Tech Contributor
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From: Conroe Texas
To add to Bill's comments - the Amp meter in these things just measures a voltage differential (so I've learned here). By removing the 2 wire connector from the back of the meter, and then measuring voltage to ground for each of those 2 wires, you will learn what the gauge is seeing.
For example, if your gauge is not showing any deflection from zero, but both wires report the same voltage as each other, then the gauge is correctly reporting what it is being told.
For example, if your gauge is not showing any deflection from zero, but both wires report the same voltage as each other, then the gauge is correctly reporting what it is being told.
Team Owner
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Army
Jeff, if the engine is running at more than idle speed, and you show no + on the meter, then it's a charging problem. Check if alt belt is tight, Check with a Multi meter on the batt contacts that you are showing at least 13.9 volts with engine running at higher than idle. Bill
Thread Starter
Drifting
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From: ar
Thanks guys, I had checked at the alternator and it is putting out 13 plus, but have not checked the battery, just assumed since it has started and ran for the last year or so the battery was getting charged. I'll put the vom on the gauge and battery this afternoon and see what I have.
Jeff thanks on the vent window advice, I was able to get the pin welded back on the frame, polished and new rubber installed and it works well and looks good.
Jeff
Jeff thanks on the vent window advice, I was able to get the pin welded back on the frame, polished and new rubber installed and it works well and looks good.
Jeff
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From: Going too fast over the hill. Iowa
I am trying to make sure all my gauges are working correctly before restoring my cluster on roadster project.
What should it read after a cold start up and when the lights are on, etc?
I have ran the car 4 or 5 times the last year and have not had to charge the battery so I feel like the charging system is working fine, just need to know if the gauge is working correctly.
Thanks Jeff
What should it read after a cold start up and when the lights are on, etc?
I have ran the car 4 or 5 times the last year and have not had to charge the battery so I feel like the charging system is working fine, just need to know if the gauge is working correctly.
Thanks Jeff
Since the battery meter only measures the voltage difference between wires connected to the horn relay and the starter solenoid, IMO your problem is elsewhere. Could be CORROSION at the bulkhead plug contacts for the two battery meter wires), the horn relay, the battery terminals, the large starter solenoid terminal, the regulator or the alternator. Otherwise it could be the regulator or alternator themselves.
What voltage do you see at the battery POSTS when the car is running?
Thread Starter
Drifting
Joined: Oct 2002
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From: ar
I am reading 12.5 volts at the battery terminals at idle and about 12.6 to 12.8 when I bring up the rpm.
At idle the amp gauge is at just a little less than 0. When I turn on lights it falls to the left and when I turn on brights it goes left some more. When I bring up rpm it moves back to the right almost to center. When I turn off lights with some rpm it moves past center just a little.
Since I am trying to replicate originality (please don't ask why) I am using 65 amp alternator and stock voltage regulator.
I am assuming after Magic V8 comments that it is working ok.
Thanks for all the help,
Jeff
At idle the amp gauge is at just a little less than 0. When I turn on lights it falls to the left and when I turn on brights it goes left some more. When I bring up rpm it moves back to the right almost to center. When I turn off lights with some rpm it moves past center just a little.
Since I am trying to replicate originality (please don't ask why) I am using 65 amp alternator and stock voltage regulator.
I am assuming after Magic V8 comments that it is working ok.
Thanks for all the help,
Jeff
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C2 of Year Finalist (track prepared) 2019
I am reading 12.5 volts at the battery terminals at idle and about 12.6 to 12.8 when I bring up the rpm.
At idle the amp gauge is at just a little less than 0. When I turn on lights it falls to the left and when I turn on brights it goes left some more. When I bring up rpm it moves back to the right almost to center. When I turn off lights with some rpm it moves past center just a little.
Since I am trying to replicate originality (please don't ask why) I am using 65 amp alternator and stock voltage regulator.
I am assuming after Magic V8 comments that it is working ok.
At idle the amp gauge is at just a little less than 0. When I turn on lights it falls to the left and when I turn on brights it goes left some more. When I bring up rpm it moves back to the right almost to center. When I turn off lights with some rpm it moves past center just a little.
Since I am trying to replicate originality (please don't ask why) I am using 65 amp alternator and stock voltage regulator.
I am assuming after Magic V8 comments that it is working ok.
Your charging system.... not so much.
You wanna see something north of 13.5 Volts at the battery with the alternator charging.
Jim
not so much.
Drifting
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From: DeBary Fl. Amateur Radio Operator K3CQR
Jeff, it's a charging problem, most likely the alt since you said only getting 13v. Is that 13.0, or more? That answer is important. Let us know the exact voltage off the alt with the engine at a high idle. Bill.
Instructor
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From: Dover Delaware
This post has me curious now. Sorry to interupt but mine is showing a positive all the time(close to +30) when the engine is running. I just changed from the generator to alternator, but you guys are saying it should zero out, is that as the battery is charged?
Drifting
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From: DeBary Fl. Amateur Radio Operator K3CQR
Michael, well it won't completely zero out depending on what acc's are on, but yes, it should go to near zero after the battery is fully charged. A 5 mile ride won't fully charge a drained battery. Bill.
Tech Contributor
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From: Conroe Texas
Micheal, also note that in your 62 you have a true meter of Amperage, where as the 63-67 has a gauge to measure voltage differential which is touted as an Amp gauge.
My 62 always shows more than 0 when running. I still have the original generator and voltage regulator in mine.
My 62 always shows more than 0 when running. I still have the original generator and voltage regulator in mine.
Thread Starter
Drifting
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From: ar
Jeff
Drifting
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From: DeBary Fl. Amateur Radio Operator K3CQR
Jeff, Bad news and good news. Bad, the alt has several bad diodes in it. Good, read Badbirdcage's offer in this thread and take him up on it. For your info a no A/C car used a 37A alt. Me, I'd go higher, especially if you do a lot of night driving. Good Luck, but it is the alt. Bill.
Thread Starter
Drifting
Joined: Oct 2002
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From: ar
The main thing is I feel like the gauge is working correctly, the alt was purchased as a rebuilt back when i put the chassis together about a year ago and and will be easy to change.
Now I need to add some fuel and make sure the fuel gauge is working and I can start redoing the gauge cluster.
Thanks again for all the input
Jeff
Now I need to add some fuel and make sure the fuel gauge is working and I can start redoing the gauge cluster.
Thanks again for all the input
Jeff