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Jerrys 49

Engine sputters when accelerating with lights on...

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Back again! My '49 Roadmaster has been treating me real nice these last few months.. however, last night I took her out, and noticed first off that my dash lights and headlights got really dim after a few miles of driving. Now I think this is odd, since I have replaced my voltage regulator (yes I've polarized it before starting the car after installation), had my generator checked out (guy said it is fine), put a new fan belt on (and it's not too loose), and... I have even been able to leave my car sitting for weeks without removing the battery cables and when checking the battery with a multimeter the numbers read 6.2 while not running. SO..... I had to return her home since my headlights (and every light) were getting to dim to drive around safely. Well... while idling in the garage (with headlights on), I pressed on the accelerator to give her some gas and- SPUTTER SPUTTER SPUTTER. I noticed that when I turned the headlights off and pressed on the accelerator the engine sounded fine and was strong. I switched back and forth with lights on and lights off just to make sure that this was happening and it is.

You guys think my battery is weak even though it shows proper voltage (Yes, I do have the proper gauge cables as well)...

Is my new voltage regulator bad??

Is my generator bad??

ANY help or comments are very much appreciated.

Thanks.

Jerrys 49

1949 Buick Roadmaster 4 Door

in sunny SO CAL!

post-82409-143139106103_thumb.jpg

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Benefits of AACA Membership.

Sounds like a dying battery or maybe short in the headlight circuit.

What was the ampmeter showing? Would the car still crank after this?

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I wouldn't think BATTERY, car should run via generator alone. Battery is made to start the car, and that's about it, IMO.

Dale in Indy

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Jerry; I think the voltage regulator needs turned up a little more,there are adjustments for volt output and amps.It maybe fine during the day,but on the border line with the lights on.What does the gauge indicate? I think the regulator just needs tweeked a little more. Mark

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Old Tank.. the ampmeter shows 6.2 on the battery with the car off. Mark.. I haven't tried to hook up the meter with the lights on. Good idea.

So here's what happened today... I tried to fire her up and..... click click click... The only sound heard is the starter trying to turn the engine over. The sound is actually probably just the sound of the Bendix. I hooked up the ampmeter and it only shows 5.8 now as opposed to last night's and prior days' 6.2 (with engine off).

So.. the question is..... perhaps I am not getting a proper re-charge from my generator with lights on?? I always noticed that when idling at first fire up, the ammeter shows charging, but when I take her out it is always in discharge. AND, if I take her out at night (like most men like to do) the lights on the dash and headlights/tail lights get dim after about 15 min. of driving her.

The generator guy said the generator is good.. my voltage regulator is new.

I am actually thinking about pursuing an Optima 6 volt and buying a cover that looks original from a local guy just to keep her show. BUT.. if I can not figure out the problem then what's the point right?

I wanna just get her new and in working order like she was in 1949.

Jerrys 49

1949 Roadmaster 4 Door

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Sounds like your generator hasn't been charging sufficiently enough to keep the battery charged and when you drive with the lights on it sucks all the voltage that's left in the battery away to the point that there isn't enough to keep the engine firing properly. Either bad generator or bad connections between the battery and regulator

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Jerry,

Just to add my $.02.

Check your battery connections AND your ground connection at the block. Mine was all corroded and I experienced the same symptoms about a year ago.

Mike in Colorado

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Jerry;The regulator is new and works well but the settings may be "close" but not exact.It was set up at the manufacturer.There are 3 contacts inside that are adjustable.Cut in/out,volts,amps.The guy that did your generator could probably explain that.When you sit at stop,with the lights on drawing from the battery the lights will dim some what and discharge,generators need speed to produce power,alternators do not.That condition will be normal.If the car is off and you dis-connect and re-connect the battery cable do you see any kind of spark?That would indicate the regulator has not "cutout" the contacts are still closed causing the battery to dis-charge even though the car is "off".I'm sure you have a clock but the draw from it would be very very minimal.Iwould take your car to the fellow that did your generator,i'm sure he could check the function of the regulator,the guys that do generators/starters are very good with regulators too!! I love the pic of your car it looks awesome!!! Good luck Mark

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I wouldn't think BATTERY, car should run via generator alone. Battery is made to start the car, and that's about it, IMO.

Dale in Indy

Dale is correct. The battery is nothing but a storage device for electricity. It stores electricity to start the car. Once done the job is complete and it sits recharging through the generator. The generator runs all electrical once the engine is started. If the generator is not up to snuff the car will run off the battery until the battery is exhausted. The car can go for quite sometime with the battery running the ignition only. Put the headlights on and the new load on the battery will drain quickly. However, for the electrical system to be 100% all of the components need to be 100%. Battery included. Charge it and get a load test done. Usually the auto parts store will load test for free. If she checks out then concentrate on the connections/generator/voltage regulator. My belief is your voltage regulator is not working.

Edited by avgwarhawk (see edit history)

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I have found that a battery test done at retail stores, ISN'T always a good measure. Recently I took a battery to the large sears automotive store/shop. They put my battery on three different testing devices, all showed it to be in good condition, but it wasn't. A new battery solved my stating issue. A simple load test by one of the hand held gauges, doesn't always tell the story, IMO.

I believe you have a generator/regulator issue, could be wrong, BEEN THERE, DONE THAT.

I wish you well,

Dale in Indy

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I took two 12 volt batteries to the local auto parts store just to have them checked on the new equipment after I charged both of them for a couple of days on an automatic charger. They both tested bad. Came home and put them both on the old fashioned carbon pile load tester and one was good/ one bad. The test is putting a load on a 12 volt battery that was charged and see if the voltage drops below 9.6 volts. One battery went below 9.6 volts and the other did not. Kept the good one and scrapped the two time loser.

I would use a down and dirty check of the 6 volt battery by charging it up over night and them come out in the morning and remove the battery charger. I would then turn on ALL of the lights and accessories and after 15-30 seconds check the voltage on the battery. If it is less than 5 volts would think it is a bad battery. If above 6 volts would check all of the connections as suggested above.

Edited by Larry Schramm (see edit history)

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