Still have electrical surging

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Triumph215
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Still have electrical surging

Post by Triumph215 »

I bought this 77 Waggy about two months ago. I ran well but was mechanically neglected, one thing going on was the Ammeter and lights surge pretty rhythmically. No problem I thought, I can fix that. At this point I've replaced a lot of worn out parts but still the surge persists, here's where I'm at.
Replaced:
Alternator, Voltage Regulator, Distributor, Coil, Ignition Module (got tired of futzing with the melted Ignition module and the mechanical advance on the Prestolite was frozen so I threw in the towel and went 78 duraspark and stealth HEI controller, works great).
Pulled dash and replaced burned out Temp and Oil Pressure gauges, dod the LM7805 conversion, works great.
Still suggest but now occasionally the surge quits for a few minutes and when the idle is low like at a stop it doesn't do it at all. But if cruising it bounces regularly between 0 amps and 30 amps. If I turn on the headlights it bounces faster but the overall draw remains the same. I can hear the alternator load up when it starts bouncing and relax if the bouncing calms down. What the heck could be pulling that many amps without burning something up?
Here in a few days I'm going to try and take it to an auto electrical place nearby but in the meantime does anyone have any ideas or ideas on how to search for it? I fear for my ignition system.
1964 Triumph TR4 with 1964 Olds 215 heart transplant
1977 Wagoneer
2009 BMW GS1200

bigun
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Re: Still have electrical surging

Post by bigun »

Check your grounds

GrandW
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Re: Still have electrical surging

Post by GrandW »

Sounds simple, but is the belt tight enough? If it's slipping it can cause your voltage to bounce.
1987 Jeep Grand Wagoneer

Topic author
Triumph215
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Re: Still have electrical surging

Post by Triumph215 »

Good points. Battery ground was poor and I replaced three cables, battery to starter, battery to engine block, engine block to frame.
I hadn't thought about the belt but it is tight, i tightened it up well when I installed the alternator but maybe the belt has a problem. I'll inspect it today.
1964 Triumph TR4 with 1964 Olds 215 heart transplant
1977 Wagoneer
2009 BMW GS1200

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Triumph215
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Re: Still have electrical surging

Post by Triumph215 »

I've been reading a lot here and at ISFJA trying to figure this out and ran across and old post referencing brown circles around the Ammeter posts on the PCB. I have these brown circle too but I can't find the original thread. The wires seen fine, no corrosion, no bubbling and the crimped connections seem good but I did notice the discoloring and wondered about that.
Do the brown circles hint of impending doom? I'm trying not to turn this into a build project but am thinking Ammeter bypass after seeing that reference to the PCB and Ammeter posts. Also wondering if my Ammeter surging can be contributing to this heat, seems likely to me.
1964 Triumph TR4 with 1964 Olds 215 heart transplant
1977 Wagoneer
2009 BMW GS1200
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tgreese
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Re: Still have electrical surging

Post by tgreese »

The ammeter bypass putting both wires on one ammeter post is very easy, and worth a try.

All the other bypass stuff just streamlines the wiring, and does not significantly change the circuit. Without the ammeter, there is no reason for the charging current to go up to the dash and back to the battery.
Tim Reese
Maine beekeeper's truck: '77 J10 LWB, 258/T15/D20/3.54 bone stock, low options (delete radio), PS/PDB, hubcaps.
Browless and proud: '82 J20 360/T18/NP208/3.73, Destination A/Ts, 7600 GVWR
Copper Polly: '75 CJ-6, 304/T15, PS, BFG KM2s, soft top
GTI without the badges: '95 VW Golf Sport 2000cc 2D
Dual Everything: '15 Chryco Jeep Cherokee KL Trailhawk, ECO Green
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Triumph215
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Re: Still have electrical surging

Post by Triumph215 »

After more research I read that only current for charging the battery runs through the ammeter. To me that indicates my bounce problem is on the Red wire side of the ammeter, do I understand that correctly?
If it's not raining tomorrow I will pull related fuses one at a time to see if isolating any of these circuits will cure the bounce.
Will pull 13B/Back up lights 15A and then run the engine
Then 12C series one at a time Hazards 15A, Tailgate relay 30A, Tail/Stop lamps 15A running the engine after each pull.
If none of that has any effect I'll peel off the wiring loom cover to the bulkhead and inspect. I need to do that anyway as I peeled some back to upgrade my ignition but couldn't find a fusable link, I'm a little concerned there isn't one.
If nothing obvious there I'll pull the dash and bypass the ammeter, I'll do this anyway but am interested to see what isolating the circuits might do before I make the bypass. I'm trying to better understand electrical systems but it's still not super clear.
If still no change I'll separate the bulkhead connector to see what there is to see in there. Will I have to destroy the seal to separate the bulkhead connector? Is this an available part or might I need to have material on hand to fabricate a new seal?
Lastly, am I way off the mark here before I spend the time on this and it's obvious to someone I'm chasing the wrong things?
Many thanks
1964 Triumph TR4 with 1964 Olds 215 heart transplant
1977 Wagoneer
2009 BMW GS1200
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tgreese
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Re: Still have electrical surging

Post by tgreese »

So much text.

TL;DR

The properly operating ammeter is effectively a short between both posts. It measures a tiny voltage drop across that short. Put both wires on the same post and try it. This an easy ammeter bypass, and will tell you if the ammeter is part of the problem.

Try one thing at a time. On IFSJA, someone suggested you disconnect the alternator as a test. I would probably take the belt off and see if the surging goes away. I'd make the belt really loose so the alternator does not turn. Divide and conquer.

For safety, do the ammeter bypass first, and leave it bypassed.
Tim Reese
Maine beekeeper's truck: '77 J10 LWB, 258/T15/D20/3.54 bone stock, low options (delete radio), PS/PDB, hubcaps.
Browless and proud: '82 J20 360/T18/NP208/3.73, Destination A/Ts, 7600 GVWR
Copper Polly: '75 CJ-6, 304/T15, PS, BFG KM2s, soft top
GTI without the badges: '95 VW Golf Sport 2000cc 2D
Dual Everything: '15 Chryco Jeep Cherokee KL Trailhawk, ECO Green
Blockchain the vote.

Topic author
Triumph215
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Re: Still have electrical surging

Post by Triumph215 »

Will be more succinct going forward.
Much appreciate your kind dedication to the preservation of these trucks and amazing patience to help so many people.
Thank you
1964 Triumph TR4 with 1964 Olds 215 heart transplant
1977 Wagoneer
2009 BMW GS1200

77Chief77
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Re: Still have electrical surging

Post by 77Chief77 »

Any updates on this issue?
1977 Chief, Wide Track, 360, TH400, QT

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Triumph215
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Re: Still have electrical surging

Post by Triumph215 »

I did the ammeter bypass, added the solid state dashboard voltage regulator, eliminated the red wire from the alternator to the firewall connector and ran a new wire with fusable link directly to the starter solenoid/battery. The problem still persists but is diminished by about half. Voltage at the battery wavers between 13.5 and 14.5 about 4 times a second but is usually a little less than that now.
My PCB had the dark rings around the ammeter posts that imply overheating so my belief is the ammeter was bad and he needle bounce was a bad gauge along with all the normal Jeep wiring issues.
It’s annoying at night but at least now I’m not afraid to drive it. One of these days soon I’m going to take it to the local auto electric shop and ask their opinion just to check my work.
1964 Triumph TR4 with 1964 Olds 215 heart transplant
1977 Wagoneer
2009 BMW GS1200

77Chief77
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Re: Still have electrical surging

Post by 77Chief77 »

Thank you for the update. Mine was pulsing so I cleaned the connections on the voltage regulator and cleaned up it's ground. The problem went away but then came back so I suspect the voltage regulator is on it's way out. I still need to do the ammeter bypass as Stucka has scared me into doing it haha, jk. I understand it's a an industry wide issue with those ammeters.

Keep us posted if you run it by a pro car electrician.
1977 Chief, Wide Track, 360, TH400, QT

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Triumph215
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Re: Still have electrical surging

Post by Triumph215 »

My voltage regulator is brand new from NAPA but I’ve gotten some surprisingly poor quality electrical parts there recently and I’m suspicious of it. The check at the electrical shop will hopefully pinpoint the problem. Will update here after they look at it.
1964 Triumph TR4 with 1964 Olds 215 heart transplant
1977 Wagoneer
2009 BMW GS1200
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Stuka
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Re: Still have electrical surging

Post by Stuka »

Assuming the voltage regulator is not the cause, having the voltage fluctuate like that typically means an issue in the alternator/regulator (yours should have an internal regulator), a ground issue (sounds like you cleaned all of those), or a short/intermittent load.

If you are stuck, try disconnecting the chassis power feed (or pull fuses) and see if the fluctuation goes away. You may have a short or a bad body ground.
2017 JKU Rubicon
Pevious Jeeps: 1981 J10, 1975 Cherokee, 2008 JK, 2005 KJ, 1989 XJ

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Triumph215
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Re: Still have electrical surging

Post by Triumph215 »

I'm going into Watsonville tomorrow and will hopefully have a chance to go by Osuna Electric and see what they think about the surging. Will keep you posted.
1964 Triumph TR4 with 1964 Olds 215 heart transplant
1977 Wagoneer
2009 BMW GS1200

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Triumph215
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Re: Still have electrical surging

Post by Triumph215 »

Went buy Osuna and it was $150 to look. I don't fault them for charging for their time but the problem is minor at this point and i didn't have them go through it. Later when I get a few other more pressing things straightened out maybe I'll go back and let them have at it.
Sorry about that 77 Chief.
1964 Triumph TR4 with 1964 Olds 215 heart transplant
1977 Wagoneer
2009 BMW GS1200
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tgreese
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Re: Still have electrical surging

Post by tgreese »

The battery has a (small) resistance, and by Ohm's law, there will be a voltage drop associated with the current through it. The regulator looks at the voltage across the battery, which is the electrochemical potential (12.6 volts) plus the charging current times the battery resistance. The charging current is the sum of the alternator output (output) minus the demand of the vehicle (load). When the load increases, the voltage drops. This acts as feedback and the regulator sends more current to the alternator field, raising the charging current and compensating for the load, returning the voltage close to the "set point" (about 13.5 volts).

This compensation is not immediate; there has to some damping in the feedback, otherwise the system could go into wild oscillations. What you are seeing is the time-lag between feedback and compensation. The most obvious source for this lag is the regulator. It has a pre-set gain that determines how quickly and how closely it responds to the feedback when there is an increased load.

I would start removing or replacing components and see if the surging goes away. I would want to measure the voltage level in real time, using an instrument that responds much more quickly than the surging, maybe an oscilloscope or a VTVM. An analog multimeter might be ok; digital mutimeters typically convert only maybe 5 or 10 times a second, and the display probably won't keep up. Then start trying to isolate the effect. First I would disconnect the alternator and watch for any surging. Next I'd try a different battery, and see if that has an effect. See what happens at each step, and use your understanding and ingenuity to isolate the problem.
Tim Reese
Maine beekeeper's truck: '77 J10 LWB, 258/T15/D20/3.54 bone stock, low options (delete radio), PS/PDB, hubcaps.
Browless and proud: '82 J20 360/T18/NP208/3.73, Destination A/Ts, 7600 GVWR
Copper Polly: '75 CJ-6, 304/T15, PS, BFG KM2s, soft top
GTI without the badges: '95 VW Golf Sport 2000cc 2D
Dual Everything: '15 Chryco Jeep Cherokee KL Trailhawk, ECO Green
Blockchain the vote.
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1978J10REDWHITE
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Re: Still have electrical surging

Post by 1978J10REDWHITE »

Perhaps remove the ALT and have it tested at a local parts house - O'reillys part store shop etc.
You can check the diodes yourself to see if they are all good with a DVM, once its out .
“New regulator" does NOT mean “OK”, I went thru several regulators last year on my Pontiac before My charging issues settled out.
ALT just provides the voltage, the REG is supposed to clip it off at the set range.

Take a good look a the wiring connections on the entire harness for strained twisted or tugged wires as their connection points if they are poor -crud oily etc will mask voltage current flow.
You need :
1. Good voltage source ~ a healthy steady voltage from the ALT.
2. Good heavy enough wires & Healthy point of connections for a good current “path” to push the Voltage to the devices.

I assume your belts are N0T slipping and your pulleys are proper concentric in shape rotation!

Absolutely look at the wire harness firewall junction box connection.
THAT is sometimes a Mucky oily crapped up mess, needing the spade connections Cleaned off to allow sufficient voltage & Current to flow and operate the system properly.

Like MANY older vehicles, the OEM “die-eleciic" in the junction box, the die-electric installed from factory, over time, age & heat etc, turns into a conduit of "CROSS electrical flow” due to it breaks down and becomes conductive, Opposite its original purpose!!
The material tar like die-electric materials in the box, works its way into the male/female spade connection points and causes lots of mysterious electrical issues..

Hope this helps out some.

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Triumph215
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Re: Still have electrical surging

Post by Triumph215 »

I can have the alternator checked. Agree that new doesn't mean it's good, have bought several bad new electrical parts from NAPA lately.
I searched through all the wiring and repaired everything I could find that was suspect.
Ground cables are all new and that made quite a difference.
Belts are new and not slipping.
Now to that pesky junction block, I'm glad you brought that up. I did the Ammeter bypass and wired the alternator directly to the solenoid. I cut the heavy red wire out of the harness and I wanted to separate the junction block to remove the connector rather than cut the wire and clean out the old grease but the block wouldn't separate. I'm finally experienced (old) enough to know that if something doesn't come apart like it's supposed to then don't force it so I reinstalled the screws and cut the wire. I covered the end well with E tape and shrink tubing. Later I read there are clips on the J block that need removed as well as the screws. Is that correct? I didn't see anything like that but wasn't looking for them either. I haven't been back in there to mess with it but how easily does that thing come apart? I would like to open it up and clean it out.
1964 Triumph TR4 with 1964 Olds 215 heart transplant
1977 Wagoneer
2009 BMW GS1200
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1978J10REDWHITE
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Re: Still have electrical surging

Post by 1978J10REDWHITE »

On the disassemble of junction box,
Make sure you are clear on this point as to prevent adding problems points if not done correctly.

Body panels as inner connect for voltage return GND are not that good, so possibly a GND wire added from BATT NEG to the REG case might add some stability here and making your ALT GND equal to the REG GND Potential.
Look to see if the TSM says the REG case is used as GND.

Re-readng the Orig post, 0~30 AMPS is huge swing like an AC compressor is trying to cycle on yet shorting almost like a thermal switch going on/off, possible on its own as being defective somehow, If you have AC Disconnect it at the dash switch or Pump under hood if possible.

You headlights likely have a relay device that draws a lot of AMPS too.

I would start unplugging as much as possible and see if this stops the cycling.
Including the idle solenoid if it is on the carburetor.

Trying to think here about getting your system to its most simplest connections in order to verify the charging system is healthy, then eliminate circuit by circuit.

Was there ever any aftermarket devices of any kind added then removed or still connected anywhere like under dash?
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