Ammeter replacement story in Hemmings.

Gerald Morris

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The ammeter ....

. A voltmeter doesn't indicate a problem until it's too late.

When the alternator dies it takes a while for the voltage to drop enough to be noticeable. Not good when you're nowhere near a safe place to pull off the road.

This I've found to be NOT so. I run my analogue d'Arsonval gauge voltmeters off the switched bus in the fuse box. When the alternator charges, the bus voltage zips up to 14.5 VDC, instead of ~12.5 normal to a good battery under minimal load. I've found in the 5 years I ran this setup on Mathilda that a 60A alternator, when charging the lead-acid battery I run, produces a +2VDC rise above the battery base line.

As soon as that alternator cut out, the drop showed instantly.
 

Sluggo

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Having the gauges in our '67 LeBaron redone and am leaving the ammeter as is after talking it through with the folks at Auto Instruments (Martinsville, VA). The following points lay out my "logic" 1. I'm not uprating the alternator (no electric fans or water pumps) 2. I will install the double Alt to Batt (dual fused) lines and 3. Will install the field load relay for the other side of the charging equation 4. Have installed new headlight harness with relays. They have assured me that the risk of fire is Greatly Exaggerated. Even if I get around to EFI, the fuel pump won't draw enough to need more juice from the alt.

I am open to criticism and conversation:)
 
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Gerald Morris

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Having the gauges in our '67 LeBaron redone and am leaving the ammeter as is after talking it through with the folks at Auto Instruments (Martinsville, VA). The following points lay out my "logic" 1. I'm not uprating the alternator (no electric fans or water pumps) 2. I will install the double Alt to Batt (dual fused) lines and 3. Will install the field load relay for the other side of the charging equation 4. Have installed new headlight harness with relays. They have assured me that the risk of fire is Greatly Exaggerated. Even if I get around to EFI, the fuel pump won't draw enough to need more juice from the alt.

I am open to criticism and conversation:)

You're probably safe, so long as no terminals corrode. THAT is one of the greatest contributors to automotive electrical fire.
 

Big_John

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I forgot to mention cleaning up the bulkhead connector and packing it with dielectric grease. Thank you Gerald
I'm not a fan of "packing the bulkhead connector".

Dielectric grease is an insulator. Look up the definition of "dielectric" if you don't believe me. Somewhere along the line, someone smeared this grease around the bulkhead connector and then it became "If some is good. more is better" and they began packing the terminals. The only way this works at all is the grease gets pushed out enough to make contact. It is done this way in large connections where they are out in the weather. Key word is "large". Even then it is used sparingly. The bulkhead terminals are small.

People disagree with me on this, but I don't have any of electrical issues that others do, so there's that.

The way to use the grease is to smear it around just the outside edge of the connector housing to help keep the seal tight.
 

Sluggo

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I'm not a fan of "packing the bulkhead connector".

Dielectric grease is an insulator. Look up the definition of "dielectric" if you don't believe me. Somewhere along the line, someone smeared this grease around the bulkhead connector and then it became "If some is good. more is better" and they began packing the terminals. The only way this works at all is the grease gets pushed out enough to make contact. It is done this way in large connections where they are out in the weather. Key word is "large". Even then it is used sparingly. The bulkhead terminals are small.

People disagree with me on this, but I don't have any of electrical issues that others do, so there's that.

The way to use the grease is to smear it around just the outside edge of the connector housing to help keep the seal tight.
Thank you. I trust you and your advice
 
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