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Ammeter bypass

diesel_lv

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I found the ammeter bypass done by MAD Electrical. Took out instrument cluster. Disconnected dash vent hose and removed vent. Removed radio. There is no way I can get my hand back there with wire cutters, crimpers, soldering gun, etc.... not from the top and definitely not from the bottom. Does anyone have any ideas? I've thought about trying to cut the black wire where it comes through off clean. Push the red wire through and connect it to the Black where they were connected at the ammeter. It's nice to have the 12v flow from both directions, but I don't think it's necessary. Please correct me if I'm wrong. By the way, this is a factory a/c car and everything installed under the dash. 1967 Coronet 440.

Thanks in advance
 
Wire cutters, crimpers and solder? I've got a 67 Belvedere. My ammeter leads have little eyelets that are held onto the ammeter studs with hex nuts. I just bolted them together and wrapped the connection with electrical tape.
 
Remove instrument cluster. Need to drop down steering column just under dash (not on floor). Three screws on top of cluster, note grounding steel strip on top. There's a few screws on bottom and speedo cable. Go to mymopar and download a service manual.
http://www.mymopar.com/index.php?pid=31
 
Wire cutters, crimpers and solder? I've got a 67 Belvedere. My ammeter leads have little eyelets that are held onto the ammeter studs with hex nuts. I just bolted them together and wrapped the connection with electrical tape.
I am referring to the MAD Electronics article. I am doing away with the spade connectors at the bulkhead and running a 10 gauge red and black wire straight though. These then get crimped, soldered and heat shrinked to the red and black wire inside the dash. The wires that are connected to the ammeter are cut then crimped, soldered and heat shrinked together also. Making a solid, safe connection.
 
Remove instrument cluster. Need to drop down steering column just under dash (not on floor). Three screws on top of cluster, note grounding steel strip on top. There's a few screws on bottom and speedo cable. Go to mymopar and download a service manual.
http://www.mymopar.com/index.php?pid=31
As I stated above, I have removed everything. I am asking if anyone know a way to reach those 2 wires way back in there? I do not have little tiny hands.
 
Leave ammeter in place and just jump alternator to starter stud?
 
So I decided to connect the solid red 10 gauge wire that I brought through the bulkhead at location "Z" on the wiring diagram to the black wire that "was" hooked to the ammeter. This black wire then goes to the large welded splice and delivers power to the rest of the dash area. This black wire came into the bulkhead at location"P" on the wiring diagram. I was able to cut off the female connector from the black wire and put a terminating cap on it so it does not arc or ground on anything under the dash. The solid red wire has a new 16 gauge fusible link that connects to the starter relay lug. The black wire that ran from the alternator, through the bulkhead via spade connectors and then to the welded splice and ammeter will now run directly to the starter relay lug with a new 14 gauge fusible link. Didn't feel like removing all of the a/c ductwork under the dash to hook it like they said. Only difference is that the dash does not get power from 2 directions, only one. But it is more than enough and is all crimped, soldered and heatshrinked. No more possible bulkhead issue with the main power to the dash.
 
Leave ammeter in place and just jump alternator to starter stud?
Thanks. I am having the ammeter converted to volt meter by Redline and gauges checked for accuracy and new volt limiter installed.
 
curious as I'm going thru the same thing except my dash wiring harness is laying on my bench so have free access to do what is needed, but considering NOT doing the ammeter bypass. I have no ac, high amp alternator, or other planned accessories that draw high amps.

I'd love to see the plan/schematic for converting to a volt meter.
 
curious as I'm going thru the same thing except my dash wiring harness is laying on my bench so have free access to do what is needed, but considering NOT doing the ammeter bypass. I have no ac, high amp alternator, or other planned accessories that draw high amps.

I'd love to see the plan/schematic for converting to a volt meter.
I am not sure what thread it is, but there is a guy on here that took an Autometer gauge I think and gutted it and put it behind the ammeter location. Otherwise, it's usually done by a company. That is what I'm having done. In that case, You still need to disconnect the ammeter and hook the red and black wire to each other. The voltmeter will get its signal separately.
 
So I decided to connect the solid red 10 gauge wire that I brought through the bulkhead at location "Z" on the wiring diagram to the black wire that "was" hooked to the ammeter. This black wire then goes to the large welded splice and delivers power to the rest of the dash area. This black wire came into the bulkhead at location"P" on the wiring diagram. I was able to cut off the female connector from the black wire and put a terminating cap on it so it does not arc or ground on anything under the dash. The solid red wire has a new 16 gauge fusible link that connects to the starter relay lug. The black wire that ran from the alternator, through the bulkhead via spade connectors and then to the welded splice and ammeter will now run directly to the starter relay lug with a new 14 gauge fusible link. Didn't feel like removing all of the a/c ductwork under the dash to hook it like they said. Only difference is that the dash does not get power from 2 directions, only one. But it is more than enough and is all crimped, soldered and heatshrinked. No more possible bulkhead issue with the main power to the dash.
Did you draw a schematic of your mod? If so can you post it?
 
When I sells the wire around wire, I suggest bypassing the ammeter and leaving ALL the oem wiring in place as long as the bulkhead connector is on good shape.

There is zero reason to connect the red/black together at bulkhead, run a fusible link and attach it to the starter relay as Mad suggest.

Take the two ring terminals at ammeter, machine screw and nylock, some shrink tube and tape and you're done behind the dash. No cutting or crimping required.
 
Here is a picture after I converted my gauge to volts...
20180227_130024.jpg

Pretty straight forward. The aluminum gauge face needed opened up and 2 small holes drilled to attach the new gauge. I bolted the black and red wire together w/ shrinkwrap as crackedback said.
 
Here is a picture after I converted my gauge to volts...
View attachment 699425
Pretty straight forward. The aluminum gauge face needed opened up and 2 small holes drilled to attach the new gauge. I bolted the black and red wire together w/ shrinkwrap as crackedback said.
I like that set up and was going to do that. But, my gauge is in the upper right and swings from the top center left to right. All volt meters that I have seen swing from the bottom left to right. Mounted upside down so as to swing from the top, it would swing right to left.
 
I am currently underhood looking at doing the ammeter bypass too. It looks like the most straight forward solution is to cut and join the original black alternator wire with the red wire to the battery/starter relay, inside the engine compartment at the bulkhead. It already has the factory fuseable link for the stock output of the alternator. If you upgrade to higher output alternator you would have to increase wire size and fuse. Obviously all splices must be insulated carefully. Am I missing something by not running a new wire?
 
If you simply splice the alternator output to the battery charge wire in the engine compartment, you will cut off the main power feed to the dash harness. Located on the dash side of the black wire at the welded splice within the dash harness. Unless the ammeter is already heat damaged by loose or high resistance connections, failed insulators, no reason to by-pass the ammeter. By-pass the charge circuit bulkhead connections first, the more common resistance/heat problem in that circuit.
 
Some photos of the actual modification on a real car would be very helpful.
Post your mod photos of the wiring if you have them, and then explain. Would be much easier to follow.
 
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