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Scott, 10.5 volts is not enough. with that alternator you should be running over 13.5 all the time. I don’t care what you switch on. What is the voltage at the alternator? Could be small wire voltage drop. I know the frustration but we always get it right in the end.
Tom
 

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Discussion Starter · #442 ·
I don't know the voltage at the alternator. I get a much lower value on my Dakota Digital instrument compared to a USB charger with a built in volt meter. My DD would read 10.4v and the USB voltmeter was reading about 11.4. Not really sure which one is correct, but I definately notice problems.

What does "Could be small wire voltage drop." mean? Are you referring to me possibly having a small gauge wire in my charging system setup? I am using a 10 gauge wire from Alternator to the battery and 10 gauge wire from the battery to the junction block which I used to replace the factor splice joint and regulator. This was the recommended setup from MAD enterprises. Again, never had my charging system running above 12 volts so I do not think the MAD setup is the fault. I am hoping it was a lemon of an alternator.

Cheers,
Scott
 
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Hello Scott,

"Small wire voltage drop" is where the thinner gauge wires can't carry as much power as a thicker gauge wire. Thinner wire has more resistance so the voltage drops, especially on a longer wire.

I also have a DD set of gauges in my EC and I see this same drop of almost one volt difference between what my DD voltmeter says and what a good multimeter indicates at the battery. Its the thin wires after the fuse panel on the way to the DD voltmeter where this problem is mostly seen. I simply add one volt in my mind to what I see on my DD voltmeter and keep on driving.

My multimeter typically measures 14.4 VDC before the e-fans and the AC kick on, measured at the battery. And around 13.7 VDC once everything is running and maybe 13.4 or so at night with the headlights on.

Rick

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Discussion Starter · #444 ·
thanks guys. i will do a couple checks at multiple points before i swap alternators. the edelbrock e-tuner also shows the same lower voltage as the DD gauges.

any idea what may have caused the issue with the fuse panel not passing electric to the accessory and ignition wires? it is either the fuse panel or the digital guard dawg ignition box causing this problem.
 

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Scott, As B52 said please check at the alternator with a good volt ohm meter before going farther. Check at battery also With motor running nothing on. If voltage is good turn on stuff and check again. On my setup you need voltage on the small wire to make the alternator work. You only have voltage on the small wire when key is on.
Tom
 

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Discussion Starter · #446 ·
Well, I pulled the fuse block and everything looked good. No damage back there. So, I figured thr problem must be at the DGD alarm box with the ignition wire taps. With the power on, all the wires were hot. So, then I traced each wire and sure enough the green ignition wire that ties into the car harness was not making a good connection. Arrgh. But, an easy fix.

So, I have the battery on a charger. When I get home from work tomorrow I will do some tests on the old alternator, then I will install teh new Mechman alternator and do a retest. I will post the photos too. Mechman has some specific instructions for testing for voltage drops at specific locations, so I plan to follow and report those tests.
 
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I am glad you found this before swapping alternators.

Are you still changing from the ProMaster 100 amp to a MechMan 170 amp, 240 amp, or the one that requires the twin 14 inch tall air turbines mounted on top of the cab?
 

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:LOL::LOL::LOL:
 

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Discussion Starter · #449 ·
Hey now, that is not funny. You know I will spend countless hours searching for those twin turbines and when i can't find it, I will design my own with linear actuators to move the turbine to a more lateral position to collect more air. i want it to look like the pod racer that aniken skywalker had in the force awakens.
 
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As a former NASA worker, I can help you out. I've put those very items on our airplanes. 😮
 

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@EL S ONE has these special mounting brackets he uses to mount them wide on each side.
Not only will these turbine alternators generate lots of real and static electricity, they also help out if your A/C isn't measuring up. Come complete with aerodynamic triple plated chrome bullet tips and are clearly marked with "Custom" badging. They come in black, white, cement and Verdugo Green and a luscoius Bomba Brown.
The prototype was first found near area 51.

But wait, there's more!
Today you get two (2) mounting kits.

Due to the classified nature and limited quantity, I am not permitted to add a link.
Yet you know who to contact.

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I have the last two. The other four were used on the Voyagers. Good luck retrieving those. 😮
 
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Discussion Starter · #453 ·
The Promaster is a 150amp alternator. The Mechman is a 170amp. Well, I did some testing and made the swap tonight. Unfortunately, I could not use the March pulley with cover. The shaft on the Mechman is very different in design. So, I had to use there billet black serpentine pulley. It is not as small as the March pulley I had on the Promaster. Nonetheless, the new Mechman outperforms the Promaster hands down.

Here is the photo journey for the install and results.


I had the battery on a trickle charger for a couple days and when I took it off with the car off I get 12.53v on the tester.
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The edlebrock reads 11.5v with car off.
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About 11.5v on the DD display with car off.
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now I started the car and turned on AC and headlights. Radio off. Car in park and not warm yet. And I get 11.99v.
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Same situation and the USB volt meter gets about 1v higher and this is consistent with all my readings.
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DD edelbrock are at 11.5v again. I should add that I was not driving in teh heat or uphill like the time when I had all these problems.
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So here is the Charge path test. According to Mechman, I hould have less than 0.1v. This is a fail. So, after reading the potential things to fix, I only have a 10g wire going from the alternator to the junction block "splice" and this is what is recommended with the MAD charging system setup.
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This is the Ground Path Test. This is a pass. So ground is good and charge wire may be too small.
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Discussion Starter · #454 ·
So here are the photos after install of the Mechman 170 amp alternator.



After installing the Mechman I fired up the car and before adding any accessories this is what I got, 14.6v.
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USB voltmeter is about the same.
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DD cluster shows about 14v.
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With AC and headlights off and radio off at idle I get a nice 14.2v on the USB display.
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DD cluster shows about 13v which is consistent for being a little lower.
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Back to the battery with everything above mentioned, running at idle.
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Now for the Charge Path Test. It is a tiny bit better, but overall still a fail.
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DD and Edlebrock are reading about the same.
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So, here are the Mechman instructions for performing a Charge Path and Ground Path test. It is important to note that the text box corresponds to the photo on the side of it, not bewlow or above it.
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So, I am going for a long drive tomorrow and a car show on Sunday. This will be another nice opportunity for a test.

Overall I am happy with the startup performance. The road test will help alot.

I plan to install a large 4 gauge wire from the Alternator to the battery tomorrow and will leave the existing 10 gauge wire in place that connects to the junction splice. This was the recommended strategy and wire size according to Mechman. I will retest the Charge and Ground paths tomorrow after the wire upgrade. It would be nice if I can reduce that Charge Path test to below 0.1v.
 

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Good Job Scott on your testing.

It seems the charger brought battery Voltage to 12.53 V.

It is then 14.6V before the images with the new Mechman alternator installed.
Do you know if any of that increase was from the older alternator bumping voltage prior to the switch?
 

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Discussion Starter · #457 ·
Old Bear, The 14.6v is with the Mechman alternator and the car running with no accessories on.
 

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Discussion Starter · #458 ·
Looks to me your biggest problem was the old alternator.
Tom
Tom, you are correct. I could not agree more. The testing did help me understand that my power wire size was too small. The MAD instructions are old and based on standard equipment and alternators. So, running the Charge Path Test was crucial to identifying this problem. I think this is a test everyone shoudl be doing with their charging system.

So check this out. Here are the results after adding the 4 gauge power wire back into my sstem like I had before folling the MAD instructions.



You can see the fat 4 gauge wire running up to the gold distribution block. This connects directly to the battery and then feed the audio system. The Charge Path test with the car running and no accessories is 0.020v. Previously this was 0.769v and the goal is to be below 0.100v.
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This Charge path test is with the car running, headlights on and AC on High. Still solid at 0.056v. Really impressed with this test.
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Lastly, I tested voltage with car running, headlights on and AC on High and get 14.85v with cold engine at idle. This is still an improvement over the reading last night of 14.06v before adding in the 4 gauge wire which was recommended by Mechman for this alternator size of 170amps.
Hood Automotive tire Motor vehicle Automotive lighting Automotive exterior



Heading out to visit Dad for Father's Day and a car show tomorrow. I will report back on the overall running of the car with AC on and hopefully no more break downs due to the power voltage drops.
 
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Discussion Starter · #459 ·
Successful drive to Vernon, AZ. I ran the AC the whole way and never saw the voltmeter dip below 13.5v. Most of the time it hovered 14.2v. I also had some rain along the way and the wipers were working great. Good day for the Elky and I hope it stays like this for the rest of the year. I also have over 800 miles since swapping the rockers and lifters and everything under the valve covers are quiet.

I am heading out to the Blazin M Ranch Car show in Cottonwood and hope to display the signboard with a beefed up pole and new attachments to prevent the wind from blowing it over. I hope it works.
 
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