Headlights go on and off

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82sbshortbed

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Took it to work this morning and on the way my head lights turn of for about 30 sec or so then come back on. This went on the whole 13 mile trip.

Also right before I got to the shop it started running like **** wouldn't accelerate stumbled and died turning into the parking lot. Fired back up and was able to park. I don't know what's up with it. Gotta be that Edelbrock carb on it.
 

Paladin

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Had similar problem just with the headlights as you descibed. Would go out then come back on whenever. Turned out to be in the wiring as best I could figure. I replaced all wiring and put new sockets, cleaned ground spots and walla Fixed!!
 

75gmck25

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I remember Ford having an overload circuit breaker built into the headlight switch, instead of a fuse on the circuit, but I don’t know what GM uses.

Bruce
 

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Lights, I would say switch, except for the stumble and fall deal, just reading I would say the rough running and dying sounds coil, module. Personally I'm learning to like Elderbrocks, simple to tune and stay that way.....I do like simple and just my opinion. So, you either have 2 seperate problems that showed at the same time, or you have an electric weasel bouncing around in there and both the lights and bad running are a sympton of the one problem. I'm hoping for the first option!!
 

82sbshortbed

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I was really Leary about taking it this morning because it's dark and the farthest I've driven it. As long as I can get back home after work then I can fix the lights and carb. It ran well all the way there at about 190 degrees but just right at the end. Guess 13 miles is as far as she wants to go. Lol
 

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I remember Ford having an overload circuit breaker built into the headlight switch, instead of a fuse on the circuit, but I don’t know what GM uses.

Bruce

The switch has an overload built in, just a little metal strip that bends and breaks contact with too much heat. Sometimes they get old, sometimes too much current draw.....
 

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Are the high beams affected also? There is a circuit breaker built into the headlight switch, it may be tripping on and off. Or, it could be intermittent open in the wiring. Start by throughly inspecting all the wiring underhood, including the sockets. Usually, grounds cause problems like this, but since each headlight has its own ground,the odds or both failing and functioning at the same time is slim.
Next time the lights fail, use a test light to check for power at the headlight dimmer switch. There will be a light geeen, and tan wire. The light green is high beam power, tan is low beam. Whatever wire remains (either light blue or yellow) is the headlight feed from the headlight switch. If power is there, and power on the tan and or geeen, your problem is between the headlight switch and the headlights.

You can also use a fused (probably 10 amps is enough) jumper wire at the headlight switch. Applying power to the green wire at the dimmer switch should cause the high beams to come on, tan should make the low beams light. If everything checks out, replace the headlight switch.
 

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As for the lousy running engine, you COULD replace the Edelbrock with a Holley, but it already is giving you trouble. Why make it worse?

My vote is a well tuned Q-Jet. Find one that fits your engine, and get a rebuild kit that includes the parts to calibrate it to YOUR. combination. Properly rebuild it, dial it in, close the hood and enjoy.
The only time a Holley can make more power than a Q-Jet (or any other carb for that matter) is if the engine requires more airflow than a Q-Jet can provide. Considering every Q-Jet ever made is capable of at least 750 CFM, you would have to have a pretty stout small block to exceed that.

How many millions of cars/trucks did GM build with the Q-Jet? They were pretty reliable. Don’t forget Ford also used the Q-Jet on some of its high performance engines. Built right, they really are hard to beat.

In my experience, most of the problems people have with the Q-Jet are brought on themselves. A cheap rebuild kit and a couple cans of carb cleaner isn’t going to get it done!!! Not to mention trying to rebuild and tune a carb with worn out throttle shafts won’t work. Then you get the people who bolt on a carb originally designed for a weezy 305 onto a big block and complain about the “Quadrajunk”.

I’m done venting now. Good luck!!
 

82sbshortbed

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As for the lousy running engine, you COULD replace the Edelbrock with a Holley, but it already is giving you trouble. Why make it worse?

My vote is a well tuned Q-Jet. Find one that fits your engine, and get a rebuild kit that includes the parts to calibrate it to YOUR. combination. Properly rebuild it, dial it in, close the hood and enjoy.
The only time a Holley can make more power than a Q-Jet (or any other carb for that matter) is if the engine requires more airflow than a Q-Jet can provide. Considering every Q-Jet ever made is capable of at least 750 CFM, you would have to have a pretty stout small block to exceed that.

How many millions of cars/trucks did GM build with the Q-Jet? They were pretty reliable. Don’t forget Ford also used the Q-Jet on some of its high performance engines. Built right, they really are hard to beat.

In my experience, most of the problems people have with the Q-Jet are brought on themselves. A cheap rebuild kit and a couple cans of carb cleaner isn’t going to get it done!!! Not to mention trying to rebuild and tune a carb with worn out throttle shafts won’t work. Then you get the people who bolt on a carb originally designed for a weezy 305 onto a big block and complain about the “Quadrajunk”.

I’m done venting now. Good luck!!

It's a BBC 454 that I swapped the 305 for. I have a level 2 Quadrajet I'm gonna put on and see if that fixes it. It's been tuned for a motor with intake and hedders from national carburetor. It's pretty much new and I have the adapter plate for it. I talked to them and he said that should be enough for the BBC but, if not they can mail me bigger jets for 20 bucks. Do I'm hoping that will fix that.
 

82sbshortbed

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The wiring is a mess from po and I think the headlight switch might be bad. He also put a tilt wheel on it so the dimmer switch is 0n the blinker switch. It has the 89 burb grille and 4 head lights. Only 2 work at a time in high or low. Low seems to be brighter but, I'm not sure. I know when I switch back and forth. One is not very bright at all. The brighter of the 2 doesn't look to be high beam bright(if that makes any sense)at all. It could be grounds too.

Maybe the stumble and bad running could be in the dizzy too. Once it seems to get up around 190 or 200 it starts running like that. I have a brand new skip white distributor I pulled off the sbc 305 too. Would they be interchangeable with a BBC?
 

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I feel if you have both problems out of no where, you have a wiring problem and you cant supply a healthy current to the coil, its losts somewhere. of course then it runs rough, then alt doesnt make juice, etc.
 

AuroraGirl

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As for the lousy running engine, you COULD replace the Edelbrock with a Holley, but it already is giving you trouble. Why make it worse?

My vote is a well tuned Q-Jet. Find one that fits your engine, and get a rebuild kit that includes the parts to calibrate it to YOUR. combination. Properly rebuild it, dial it in, close the hood and enjoy.
The only time a Holley can make more power than a Q-Jet (or any other carb for that matter) is if the engine requires more airflow than a Q-Jet can provide. Considering every Q-Jet ever made is capable of at least 750 CFM, you would have to have a pretty stout small block to exceed that.

How many millions of cars/trucks did GM build with the Q-Jet? They were pretty reliable. Don’t forget Ford also used the Q-Jet on some of its high performance engines. Built right, they really are hard to beat.

In my experience, most of the problems people have with the Q-Jet are brought on themselves. A cheap rebuild kit and a couple cans of carb cleaner isn’t going to get it done!!! Not to mention trying to rebuild and tune a carb with worn out throttle shafts won’t work. Then you get the people who bolt on a carb originally designed for a weezy 305 onto a big block and complain about the “Quadrajunk”.

I’m done venting now. Good luck!!
im one of the people who are completely open to a quadragold, but its a matter of sending it in for rebuild because im not that level. i rebuilt a 16hp briggs carb, it only took 2 tries on the main part, and 4 tries on the diaphram fuel pump.

ive been buying new small engine carbs since then.
 

gotyourgoat

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Well, it could be all of the things mentioned.

Could also be a bad battery, an alternator dying or some loose connections. Just to give you a few more things to worry about. :eek:

I'd look closely at the burb headlight conversion wiring.
Only the highs or the lows should be on at any given time with a multiple light setup.

The floor switch isn't hooked up is it? Guessing the tilt wheel and the lights came together.
 

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