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1949 Ford Coupe RESURRECTION
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Discussion Starter · #1 ·
This has been an issue since I built the car... off and on... and other minor issues...
Picture attached but I didn't show the other connections to the fuse box, etc. except on the first drawing. When I first built the car I had a 60 amp alternator and it wouldn't keep up with the two fans, 1,600 watt sound system, A/C, headlights, etc. Drove to g/f's house one relatively hot evening (headlights, a/c, radio blaring..), and the battery read less than 12 volts (dash mounted volt meter) when I got there ......So I bought a Proform 100 amp and things were better.

I thought (and I still may have) a battery issue, but this is suspicious enough to investigate. Yesterday I stopped at a 7-11 and then had to get a jumper from a nice fella who pulled in. HATE THAT!

So today, I ran a few voltage/amperage tests on the system. I didn't draw in the entire circuit(s) but just my readings at the alternator and at the trunk mounted battery. What has me wondering, is that with all accessories on (a/c, headlights, fans, amplifier/radio, interior lights, etc. The output amps only reads 47.7, with only 0.51 going to the + of the battery (the rest going to the accessories/loads), and output voltage at the alternator of 13.2 volts and 12.6 at the battery.

The highest voltage at the alternator this afternoon was 13.8V with no loads, (although I have seen it on my dash mounted two decimal digital voltmeter as high at 14.6 volts at times) and 13.2V fully loaded. Would that be my voltage regulator or diodes in the GM style single terminal internal regulator? OR something else. I'm comfortable that all connections are good and the belt is good and tight. Thanks in advance for your thoughts.!!!

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I'm fairly confident that your 100 amp 10SI alternator is severely overloaded. 47 Amps is about all you'll get from any 100A SI series alternator. And it's entirely possible it's burned out some internals.

There's a reason GM developed newer alternator designs when cars started coming with electric radiator fans.

With electric fans, you should be looking for at least a CS-130 , and with that stereo, maybe even a CS-144D or AD244.

We just upgraded one car from a 10SI alternator to a 105A CS-130 unit. I'm not sure we've got enough alternator on that one yet, but I was pressed for time and had to get it running.

Also, with the battery in the trunk, and a high amperage alternator, you may need a larger cable from the starter to the battery. On another car I care for that has a 145A alternator (AD244 design) and the battery in the trunk, we weren't getting full charge with 2AWG cabling from the battery to the starter. Upgrading to 1/0 AWG cable from the battery to the starter resolved charging issues and weak starting problems.
 

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I agree with RacerX-, and here are my suggestions:
-make a list of ALL of your loads (the Manufacturers of your components should have the specs or get them online, add them up and add 15-20%-
(I found over 180 Amps in my Car, and initially installed a 185 amp, then upgraded to a 240 Amp alt))-
There is no downside (other than weight) to oversizing your charge cables, so go big (1/0 AWG), and run similar sized ground wires from the Alternator case to the block and chassis grounds (if you are running Aluminum heads they are terrible grounds)-
The CS130 is a great Alternator below 100 Amps, but it struggles above that as it needs a lot of airflow to keep cool, as the fan isn'tbig enough (they can also strugglewith idle Amps)-heat and airflow can be a problem in a tight engine bay-I like the Nippondenso Alternators as they have a large internal fan-
 

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This has been an issue since I built the car... off and on... and other minor issues...
Picture attached but I didn't show the other connections to the fuse box, etc. except on the first drawing. When I first built the car I had a 60 amp alternator and it wouldn't keep up with the two fans, 1,600 watt sound system, A/C, headlights, etc. Drove to g/f's house one relatively hot evening (headlights, a/c, radio blaring..), and the battery read less than 12 volts (dash mounted volt meter) when I got there ......So I bought a Proform 100 amp and things were better.

I thought (and I still may have) a battery issue, but this is suspicious enough to investigate. Yesterday I stopped at a 7-11 and then had to get a jumper from a nice fella who pulled in. HATE THAT!

So today, I ran a few voltage/amperage tests on the system. I didn't draw in the entire circuit(s) but just my readings at the alternator and at the trunk mounted battery. What has me wondering, is that with all accessories on (a/c, headlights, fans, amplifier/radio, interior lights, etc. The output amps only reads 47.7, with only 0.51 going to the + of the battery (the rest going to the accessories/loads), and output voltage at the alternator of 13.2 volts and 12.6 at the battery.

The highest voltage at the alternator this afternoon was 13.8V with no loads, (although I have seen it on my dash mounted two decimal digital voltmeter as high at 14.6 volts at times) and 13.2V fully loaded. Would that be my voltage regulator or diodes in the GM style single terminal internal regulator? OR something else. I'm comfortable that all connections are good and the belt is good and tight. Thanks in advance for your thoughts.!!!

View attachment 626027
When you're testing total amp output what are you using to load the system.
 

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When I said "load" I meant turn on all items that use electricity
To test true alternator out put you need an AVR tester with a Carbon Pile load. You put the Amp clamp around the Battery wire from the Alternator and Pos cable. Turn off all accessories run engine at 1500 -2000 Rpms. With the tester heavy leadsconnected to battery posts. Adjust the carbon pile load down to approx 12 volts read the amperage. That is total alt amps available. Let the engine idle and voltage stabilize. Voltage at battery should be about 14.1-14.5 volts. If you have a Rated 100 Amp alternator you should get approx 90 amps or a bit more at 2k rpms with carbon pile load. All accessories off. If you do the Alternator is working at It's total capacity. You also use the carbon pile load to test the Battery. Engine off heavy leads connected to Battery terminals. Amp Clamp around the Tester heavy positive cable Load carbon pile down to 12 volts see what amp meter reads.
 

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Another option, if you can get the alternator out easily is to take it to your FLAPS* and have them run it up on their tester and see if it's good. Most can print a report showing how it performs and identifying any faults found with the alternator.

re:
The CS130 is a great Alternator below 100 Amps, but it struggles above that as it needs a lot of airflow to keep cool, as the fan isn'tbig enough (they can also strugglewith idle Amps)-
I agree that for this one, that's probably not the best choice. But a CS-130 does much better at idle than a 10SI. I wish I had the horrible performance curves on a 100A 10SI unit. I do have the test report that came in the box with the remanufactured CS-130 that I just installed. Here's the report on the one I installed this week.

Font Parallel Pattern Rectangle Document


We're getting about 80A out of ours at 700RPM engine idle speed (~2100RPM alternator shaft speed). It goes up quickly from there. It's not as good as a AD244, but it's way, way better than a 10SI rated at even 140A. The SI units I've seen tested are all well below 50% of their rated amperage at 2000RPM alternator speed, and the curve is much more gently sloped on those, reaching rated capacity right near 6,000RPM alternator shaft speed (usually around 2000RPM +/- engine speed depending on pulley ratio).
 

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Good grounds are a must especially with trunk mounted battery. Install dedicated ground straps from body to frame, engine to frame, and battery to frame or even better to engine or transmission. Think about it. Body, engine, trans, exhaust system, shock absorbers, and suspension are all rubber mounted. I've seen cars where the only grounds were the speedo cable and e brake cable. Definitely not good enough.
 

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OK, you're drawing 46 amps from the fuse panel, which drops alternator voltage a bit much. How much current do your cooling fans draw, and how are they connected? I suspect they are your largest current draws, unless the stereo system is truly 1600 watts RMS, and not some pie-in-the-sky peak power rating. Heck, even 400 watts RMS would draw 30 amps.

Sounds like the guys above have good advice about a higher capacity alternator and 1/0 battery cables. But the alternator seems to be the major suspect, not only from a capacity standpoint, but you've seen its low-load output voltage jump up and down. I'd do the alternator first and then tackle the battery cables if necessary. But do double check grounds from negative battery cable to block, and then block to to frame and body.

There's another thread started by Racer-X on installation of a CS-130.
 

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1949 Ford Coupe RESURRECTION
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Discussion Starter · #12 ·
Thanks guys.... once again I've learned a lot in just a few minutes! Since the mounting on the engine is very tight with clearances I was concerned with going with a CS 130 but I just reviewed dimensions and it appears that it's pretty much the same as what I have installed now. Anything any larger is pretty much out of the question without some major modifications. There seems to be dozens and dozens of alternator vendors and I'm guessing three quarters of them are made in China... Any recommendations on a high quality CS 130 alternator?
 

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I had the same issue (size/Amps), and searched for a CS130 alternative-
This is what I ended up with, and it is a direct replacement for a 10SI/CS130 in size.
Extreme price? Absolutely, however there are now many copies of this design at much lower pricing (the Flaming River one comes quickly to mind, as well as others), but even at lower amperage ratings they have superior idle amps compared to a CS130-
They are US built (but overseas guts)-
 

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1949 Ford Coupe RESURRECTION
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Discussion Starter · #14 ·
THANKS, 35Window... yikes, well you are correct about the pricing.. but it looks like these are sorta like TWO alternators in one.... seriously considering this... hard to do... retired... SS... hmmmm...
 

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I've always had good service from AC Delco rebuilt starters and alternators. Most, if not all, are rebuilt in Mexico, but at least it's an AC Delco facility, not some low bidder Chinese factory.

Make sure you get one setup for proper rotation.
 

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Thanks guys.... once again I've learned a lot in just a few minutes! Since the mounting on the engine is very tight with clearances I was concerned with going with a CS 130 but I just reviewed dimensions and it appears that it's pretty much the same as what I have installed now. Anything any larger is pretty much out of the question without some major modifications. There seems to be dozens and dozens of alternator vendors and I'm guessing three quarters of them are made in China... Any recommendations on a high quality CS 130 alternator?
Just because its made in China doesn't mean the quality is good , bad or indifferent . The cost of doing business in the US chased everybody out ,offshore is all that's left !
 

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Since the mounting on the engine is very tight with clearances I was concerned with going with a CS 130 but I just reviewed dimensions and it appears that it's pretty much the same as what I have installed now.
Correct. If a 10SI is in there now, a CS 130 will fit on the same mounting system. They are the same spacing on the mounting holes, and about the same size overall.
There seems to be dozens and dozens of alternator vendors and I'm guessing three quarters of them are made in China... Any recommendations on a high quality CS 130 alternator?

Also, if you have v-belts, the CS-130 for the 1986 Camaro 4 cylinder comes with a v-belt pulley already installed. No swapping of pulleys required. AD-Delco 335-1022 or equivalent. There's also one that's clocked at 3 o'clock for the plastic connector (with the pivot point straight down). I don't have the part number handy for that one, or the application.
When I don't need it right freaking now, I prefer to get an AC Delco unit from RockAuto.com.

When I need it right freaking now, and I need quick warranty support/replacement, I go with the best local FLAPS* that's close by. Most of the remans available locally (in the USA) are rebuilt in Mexico. I think someone else already pointed that out.

AC Delco units may be Chineseum these days, but they have a good warranty, and they seem to be fairly good about quality control with their Chinese sources.

Buy from a reputable auto parts dealer or reputable online source. I've seen counterfeit stuff from both fleaBay and Amazon. If you know how to identify the counterfeits, you can generally return them (free returns for Amazon, you often have to pay shipping with fleaBay vendors). The only issues I've ever had with RockAuto has been with stuff marked "private label packaging." I avoid that unless I'm willing to gamble. It's often not what they say it is. Whether it's better or worse than what they claim is a crapshoot. I've gotten counterfeit junk with that disclaimer, and I've gotten very high quality stuff from high end, low volume sources as well. RockAuto seems to just guess on the "private label packaging" stuff, and they guess wrong as often as they guess right.

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*FLAPS = Friendly Local Auto Parts Store
 

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1949 Ford Coupe RESURRECTION
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Discussion Starter · #18 ·
Well, guys......after doing some shopping/investigating/reading reviews, I just ordered a Chrome CS130 - 160 Amp by ProForm. They are factory tested with a performance data sheet....128+ bucks plus tax and free shipping from Summit ... strange that the S10 and S20 are both higher priced .. I will report back when she's got the "new heart"..
 

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You really need a volt meter this tells you the pressure of the current. Electrical pressure is like any other it goes from higher to lower. Amps is a measure of how much in volume essentially not the force of that volume.

Problem with Amp meters is most are really volt meters that are calibrated in an amp scale whether that’s anywhere truly representative of the amps actually flowing is dubious at best.
A real amp meter has an expensive shunt inside which adds a lot of cost so as I said most automotive amp meters are really just volt meters that are calibrated with 0 being 12.4 volts and more than 12.4 being positive volts displayed as amps with volts under 12.4 being shown as negative amps .

So what .51 amp really means without volts being known is pretty questionable especially when what being displayed likely is inside the manufacturing tolerances error of the gauge.

Batteries, they fail in several ways but a common is shorts develop between the plates of a cell this of course can happen in one than more sell. This can be a spider web of material deposited on a plate such that it makes contact with an adjacent plate. A battery is just a plating solution not unlike the process of caroming parts and if you’ve ever seen parts just out of solution you know their surface is rough not bright and shiny. Same similar goes on in the battery with these plate onto the negative plate than replace back to the positive, rinse and repeat with each discharge and recharge cycle. The other thing is these pieces of material break off and sink to the bottom if the case and oxidation products produced also fall to the bottom if the case making a conductive sludge. When this stuff ties any combination of plates together their individual capacities are lost. The amperage supply from the battery is decreased where one of the first places this is seen is the starter won’t turn the engine over.

The only surefire test is a load test to see how long the battery will support a certain load. Then recharge and repeat that load, battery manufactures publish these and test stations should have this data.

In your case there are three possibilities the first you suspect that the alternator cannot support the loads and have enough reserve to charge the battery. The second stand alone is the battery is internally shorted in the plates reducing its capacity and may possibly be acting as a load to the alternator’s other activities. The third is both may be present.

Bogie
 

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1949 Ford Coupe RESURRECTION
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Discussion Starter · #20 ·
I forgot to mention that I'm a retired registered professional engineer and I'm 79 years old and I understand volts and amps. I used a DC clamp ammeter which actually measures electron flows or at least the magnetic field created by the electron flows. My illustration that is posted as part of my original shows amp and volt ratings under various conditions. The battery will hold a good charge for quite a few days even with the sizable parasitic loads ( clock, dash mounted volt meter, radio memory, remote door lock system) that are in the The Judge. That's why I just went ahead and ordered the CS130... And no it probably won't actually put out 160 amps, but it certainly will put out more than 49 under load at 12.2 volts. I will keep you posted.
 
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