MAD electrical upgrade question??

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4spdragtop

4spdragtop

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So the 67 cuda is doa and symptoms are leading to original ammeter. Ive read the MAD upgrade article.
Instead of pulling cluster ( big job, ac radio etc lol) Can I not just snip the large red and black wires (black one after the splice)
And loop together closer to inside bulkhead connector?
Not pulling cluster would save me quite a bit of time and bs

Cheers
Steve
 
Well, sort of.

The black wire is connected to a welded splice in the harness and has a couple different legs coming off of it. Just make sure you find the one between the ammeter and the splice!

Pulling the instrument panel is not that bad if you lower the column. You don't have to pull it all the way out either, just enough to reach in to be able to detach the wires from the back of the ammeter.
 
Cool if it doesn't have to be completely removed all the better. I figured cutting between ammeter amd splice.
Thanks Ram!
 
4spdragtop said:
So the 67 cuda is doa and symptoms are leading to original ammeter. Ive read the MAD upgrade article.
Instead of pulling cluster ( big job, ac radio etc lol) Can I not just snip the large red and black wires (black one after the splice)
And loop together closer to inside bulkhead connector?
Not pulling cluster would save me quite a bit of time and bs
Click to expand...

That would work but I was able to reach in up behind my cluster and loosen the 2 nuts and slide all of the wires onto one stud. Took about 5 minutes.

Cheers
Steve
 
Last edited by a moderator:
I don't like the way mad suggests doing the wire around.

You need to get the two wires connected at your ammeter.

IMO, leave the factory wiring alone and add a charge wire from alt to starter relay.

Let me know if you need anything. Been building charge wires for a while
 
I guess if you can, reach up and disconnect the wires from the ammeter. But... you may not have enough length/room to do what you need to do, space is pretty limited back there and you most definitely do not want to half *** splicing those two wires together. They need to be joined with a butt connector, soldered and heat shrink tubed, not just twisted together and taped.

All I am saying is that if you don't want to pull the cluster then at least make sure you can splice the wires competently with it in place. If not, then it's really not a big deal to pull it out.

You could also do what Rob suggested and put the charge wire to the relay but the other part of the equation is the ammeter wire connection at the bulkhead. The connections inside can corrode over time causing excess resistance which is why the ammeter can melt.

If you don't splice the wires behind the gauge, at least pull the ammeter wires out of the connector, clean them if necessary, pack with dielectric grease and re-connect making sure they are tight.
 
I choose to believe the fault is before that gauge. If not the male/female service disconnect on the fusible link, the link itself, or the bulkhead terminals. I wont argue that OEM amp gauges have failed but those failures are far out numbered by those other members in this current path. I challenge you to prove the instrument itself is the fault.
Any "work around/bypass" method suggested above would work. All lead to the same end result too. A dead instrument. Without some indication you cant know if you fixed anything nor will you know when there's a problem tomorrow.
Maybe you already have or plan to have another instrument mounted somewhere.
Converting the OEM amp gauge to a volts gauge is the most practical route but... more effort than R&R the panel is required. That doesn't address those more typical points of failure either.
 
RedFish said:
I choose to believe the fault is before that gauge. If not the male/female service disconnect on the fusible link, the link itself, or the bulkhead terminals. I wont argue that OEM amp gauges have failed but those failures are far out numbered by those other members in this current path. I challenge you to prove the instrument itself is the fault.
Any "work around/bypass" method suggested above would work. All lead to the same end result too. A dead instrument. Without some indication you cant know if you fixed anything nor will you know when there's a problem tomorrow.
Maybe you already have or plan to have another instrument mounted somewhere.
Converting the OEM amp gauge to a volts gauge is the most practical route but... more effort than R&R the panel is required. That doesn't address those more typical points of failure either.
Click to expand...

I believe the main thrust of eliminating the ammeter is because ALL the current in the car goes through it. Therefore, any fault in the system due to resistance, bad ground, etc. can potentially increase the chances of it frying even if the fault is not in the charging circuit itself. The gauge is certainly not the most robust thing in the car.

The ammeter was fine when the cars were new but 30-40-50 years down the road, the gauge can wind up being the 'sacrificial lamb' of the system. Wires get frayed, insulation cracks, connectors get pulled apart or corroded yada yada. The worst is if and when some dumb *** hacked into the harness to wire in a stereo or some crummy gauges.

I've messed with these cars for long enough now to know that even if a car looks outwardly OK, the wiring is probably shot. At the least, it should be gone over carefully, cleaned up and re-installed with sound methods.
 
Thanks all for the advice. I just finished pulling my aching arse from the front floor of the car. I removed AC diffuser to see if its remotely feasible to do it from under dash. Not a damn chance! Lol. Sooo gonna pull bezel at least partway. Reasons to pull.
1 Ammeter bypass.
2. Factory tach needs calibrating. (Under warranty)
3. Some dash leds non op.
4. Dbl chk dual front speakers I installed in spring.
Damn this **** snowballs lol

Under dash harness in great shape. I believe they are M&H repops, as 2 outta 3 under hood harness are M&H and in great shape.

Only damage to wiring/bulkhead that Isee is a slight melt point on bulkhead when fusible link under hood burnt up.This happened 4 years ago when Dad bought the car and was due to a bad alternator (thanks to Dels diagnosis). Melting was minimal on bulkhead and no damage to any wiring inside cab.

Ben I have a Demon IVR I purchased from you. Is this something that can be installed relatively easily? I guess like you said it would need a complete R&R ??

Also I would like to add a Volt gauge. I have an aftermarket set of Coolant Temp and Oil psi mounted under dash. Lots of room to add the 3rd gauge.

Thanks all!
 
The amp gauge is the best built/most rigid of the grouping.
I consider any gauge as a news reporter. They shouldn't have the ability to interrupt or shut down the story they're reporting. So yeah this design has a Clark Kent potential. That way of thinking is the only reason I converted my amp gauge to a volts gauge.
Back to Steves car. He stated its suddenly DOA. I read that as no current inside at all. I can't imagine a alt gauge suddenly and completely interrupting current flow. Anything is possible, but what is more likely ? A burned open fusible link or one of the related spade terminal connections out there under the hood. I've seen too many cases where some add on ( stereo, gauge pod, fog lamps, etc.. ) inside was the route cause too.
So Steve, Did you recently add a lighter well to this center console ? If so, Is it possible that you unknowingly created the new problem ? Shifter linkage pinched/cut a wire maybe. Chit happens
Your IVR question... Since that isn't directly related, lets save that for later.
 
Thanks Ben. The only recent electrical changes I have made.

1. Replaced 4 yr old battery under warranty.
2. HL relay kit in spring. No issues with install. Works great.
3. New alt last year or year before. Great no issues.
4. Some under hood wires replaced/repaired this week (coil neg to bulkhead gray, blower mtr green wire to bulkhead, fusible link connector cleaned, added external ground from VR mount to batt -ve) This was done this week.
No signs of issues until 3weeks ago when alt gauge started to fluctuate also one instance there was an odd smell that did NOT originate from me.

Thanks!
 
RedFish said:
The amp gauge is the best built/most rigid of the grouping.
Click to expand...

I was not implying the gauge was at fault.

What I was saying was that it can be a problem since a rather large amount of current is running through it under normal circumstances. If there is an issue somewhere else and e the fail safe system (fusible link, fuse etc. ) fails to mitigate the problem, the potential for a melted gauge goes way up.

A melted amp gauge is not the fault of the gauge in any way shape or form. But, if it's only designed to handle a certain amount of current before it fails, any added, unregulated or extra current is going to be a bad scene, no?
 
KitCarlson said:
A loose connection with amperage, can burn up a good part.
Click to expand...
Agreed, and the original amp gauge is a good part (at least in my B-body :D), with clean and tight connections it can handle a lot of amps without a problem. Myself I have a modern 100 Amp alternator feeding thru the original amp gauge, upgraded wiring though.
 
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