Low Voltage
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From: Ventura, CA
Low Voltage
Im having a problem with the voltage in my 63 being low on idle and on power (around 10-11 volts idling and 13 max on power). The battery in the truck is brand new and the alternator was just rebuilt. i do have an aftermarket stereo system in the truck but even with the stereo off the voltage is still low. The motor is a 302 out of a Bronco that was just rebuilt. Could it be that the pulley on the alternator is to small?
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From: Rossmoor at Seal Beach
Im having a problem with the voltage in my 63 being low on idle and on power (around 10-11 volts idling and 13 max on power). The battery in the truck is brand new and the alternator was just rebuilt. i do have an aftermarket stereo system in the truck but even with the stereo off the voltage is still low. The motor is a 302 out of a Bronco that was just rebuilt. Could it be that the pulley on the alternator is to small?
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ill double check that its not hooked up to the old regulator. i didnt do the swap one of the POs did so i dont know off the top of my head. the shop that rebuilt the alternator tested it after so i seriously doubt the alternators bad.
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From: Rossmoor at Seal Beach
Another thought that came to mind, when the engine was rebuilt, did you use the stock crank Pulley, or go to an underdrive pulley as is very popular now? That would give you a smaller crank pulley which would slow down the alternator also! Smaller at the source means lower RPM at the alternator, it is the opposite of the Alt. Pulley. Smaller on the crank slows all of the other pulleys down. And as for the alternator being fine, I have had them rebuilt and fail right away there is no guarantee that it won't fail. You may have a guarantee for repair if it does though. Don't overlook any possibility.
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the crank pulley is still the stock crank pulley. the voltage is higher than it was before the alternator got rebuilt but it still seems low. the pulley seems like a cheap fix should i try it and see if that solves it?
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From: Rossmoor at Seal Beach
I would ckeck everything out first! Now when you are checking voltage at the battery, are you checking the idle after revving the engine up, some alternators don't start sending power until they have hit a certain rpm, after that they are okay at idle, but not before. I am assuming that you are using a standard voltmeter, and not just your dash guage? Guages can be incorrect. Mine shows 12 volts when I test at 13.5 at the battery, and it will go up to 13 when I bring the RPM up, and the voltmeter at the Battery will then show 14.3... lIke I say always double check everything. If you have a voltage regulator it will look like a metal box about 3in. by 2in, about 2 inches tall with a wiring harness with 4 wires or so going into it they are usually black in color, and frequently fastened to the right inner fender. Also how many wires come from your alternator? that is an indicator of what your set up is! 4 wire usually is a generator, 3 wires most often an externally regulated alternator, 1 wire is an Alternator. This is just a general guidline, the 1 wire most likely will actually have 2 wires, one is the positive lead to the Batt, and the other is the GEN or ALT idiot light lead
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Ok I'll have to double check everything when I get back into town for spring break. The truck is an hour away from my school and I have no way to get there till break. Thanx for the help
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Cargo Master
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From: Concord, CA
I would start at the voltage regulator first. Good chance it could be the original one. While they are adjustable there were very few who knew of it and how to do it. Voltage, at the battery, should be at least 14V even with rpm around 800. All mine measure that today. They all previously had point regulators which were adjusted correctly. However, voltage was not what one would call constant. That was obvious in the Cougar and Mustang where the interior lights would flicker at idle. So I saw a guy on eBay selling a bunch of NOS Motorcraft electronic regulators for $7.50 a piece! Bought them all and put them in all the Fords with the original covers now on them. Voltage is a constant 14.2V and no more flickering of lights.
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From: Rossmoor at Seal Beach
I would start at the voltage regulator first. Good chance it could be the original one. While they are adjustable there were very few who knew of it and how to do it. Voltage, at the battery, should be at least 14V even with rpm around 800. All mine measure that today. They all previously had point regulators which were adjusted correctly. However, voltage was not what one would call constant. That was obvious in the Cougar and Mustang where the interior lights would flicker at idle. So I saw a guy on eBay selling a bunch of NOS Motorcraft electronic regulators for $7.50 a piece! Bought them all and put them in all the Fords with the original covers now on them. Voltage is a constant 14.2V and no more flickering of lights.
Part of the issue is that he thinks he has an internally regulated alternator, if so there would be no external regulator, or at least there shouldn't be! He has to check and see what his system is before jumping to the regulator. If he has a generator with regulator system then the first suspect is the regulator, but if it is a trua alternator then that is a moot point! he does after all have a latter model 302 which most likely does have an Alternator.
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Part of the issue is that he thinks he has an internally regulated alternator, if so there would be no external regulator, or at least there shouldn't be! He has to check and see what his system is before jumping to the regulator. If he has a generator with regulator system then the first suspect is the regulator, but if it is a trua alternator then that is a moot point! he does after all have a latter model 302 which most likely does have an Alternator.
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From: Rossmoor at Seal Beach
Hey that is great news! awesome! I don't trust the OEM dash instruments, as they have never been very accurate. I have been swapping mine out bit by bit, but have been looking lately at the newer 6 in 1 digital gauge sets for the round face dash panels. The nice part is that they are programmable and can be zeroed for accurate readings . At 600-700 bucks it is a bit to shell out, but to replace all of the gauges with one digital unit that is not too bad. I still like the look of the OEM though. The other plus for the Digital is that they sure clean up the wiring behind the dash. Ahh I am still on the fence about that.... But other issues need to be dealt with first! Again Congrats on that! 
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From: Ventura, CA
ya i have stock the stock speedo, temp and fuel gauges and i modified the speedo housing to used a factory oil pressure gauge. then since i have the three gauge dash panel i put in an autometer tach and voltmeter. im going to post pictures of the dash tomorrow once i can take pictures
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