Ammeter and Voltage Meter - Not bypassing

[71_Duster]

It was a few years ago and I don't remember the cost is was a few hundred bucks and with Canadian exchange rates and shipping it wasn't super cheap but being in the U.S would sure help the cost. Shoot them an e-mail and they should be able to give a pretty good estimate.

The thing to remember about your amp meter is that everything the alternator puts out MUST go through that gauge otherwise it's not accurate. As things get older that's a lot of current through those connections and its the weakest link in the system. I've by-passed it on both my cars as shown in the MAD link and haven't regretted it one bit. The Duster has a Rallye dash that was all redone so I didn't want a dead gauge. They rebuilt it into a volt meter and added a scale to the face to show the volts.

 

[Shorthorse]

Both ends are dis-connected from the gauge. Attach ends together and insulate. It's one solid wire, at that point.

Would you foresee a possible issue if you remove one wire from the amp meter and simply attach it to the same post as the other wire?

 

[Ranger16]

Probably not, but why? Why not just pull both and use a screw and nut to attach them together and then insulate the joint?

 

[mmissile]

That's exactly what I've done on several old mopes.

 

[khryslerkid]

Would you foresee a possible issue if you remove one wire from the amp meter and simply attach it to the same post as the other wire?

Probably not, but why? Why not just pull both and use a screw and nut to attach them together and then insulate the joint?

I don't see the difference...

 

[HawkRod]

Both ends are dis-connected from the gauge. Attach ends together and insulate. It's one solid wire, at that point.

The problem isn't the gauge. Take a look at one and you'll see there is quite a bit of metal there. The problem is that you are running all this power through the terminal block in the firewall with a little spade terminal. THAT'S what will get you in trouble. So if you disconnect your gauge but leave the terminal block, you have not particularly helped yourself.

By that way, this will be another chance to plug fire extinguishers. Every single one of us should have one, as these old cars can have wiring issues. It would be a shame to lose one due to a short - buy one and have it in the car - it's cheap insurance.

 

[mmissile]

WRONG. The last one I did, the terminals were loose in the gauge. I also don't think an electrical fire is gonna be put out by a fire extinguisher. It'll have to eat itself up, or lose the power. Cable cutters would be more useful. If I had a bad electrical fire...I'd hope it would be a write-off.

 

[Ranger16]

For what it's worth, mine had loose connections on the gauge terminals. The studs where not screwed in tight. Rather than tightening them, I pulled the wires and connected them together. I have checked my bulkhead connectors several times and to my surprise, they where all clean. Last summer I pulled all 3 connectors and lubed the contacts with dielectric grease.

 

[HawkRod]

WRONG. The last one I did, the terminals were loose in the gauge. I also don't think an electrical fire is gonna be put out by a fire extinguisher. It'll have to eat itself up, or lose the power. Cable cutters would be more useful. If I had a bad electrical fire...I'd hope it would be a write-off.

I'm not trying to start a fight, but I respectfully disagree. First, loose terminals are another issue, and that could cause arcing, but that's not what the concern was. You could have loose screw terminals in lots of places in the electrical system, but I'm sure no one is suggesting we tear them all out. Absolutely we should make sure all those connections are good, but that's another issue.

When you put a lot of power through a wire, it generates heat. The smaller the cross section of wire, the more heat. That heat is obviously what can cause a fire. The alternator gauge is especially prone to this concern because all power except for the starter goes through it, so a lot of power goes through the gauge. The firewall terminals are a problem because they can have limited contact points, and that makes them act like a thin wire. For this reason many drill them out and pass a bigger gauge wire directly through.

An electrical fire isn't the electricity burning, but other stuff like insulation and other plastic parts burning from it. Yes, a fire extinguisher WILL put that material out. However, even if you don't believe it will, I still hope you carry one in case you have an under-hood fire. I'd hate to see anyone lose their car over something that could be avoided.

Hawk