On my '76 , I replaced the stock alternator with a 100 amp, changed the reg(100amp), also. But when I turn the headlights on, they are very dim. I've had the headlights for several years, and wonder if they are slowly going out? I put a full charge on the battery also.

 

check the voltage rite at the back of the headlite wiring term. an see what you get with the engine at idle with all acc. off. most times you just need to clean the connecter going to the lites ,.Ford has allways had a problem with the switch they run to small a wire . If I remember its a blue wire with a red tracer on it . The lites normally have less then 12 volts going to them , on older cars ( my sons 73 maverick his headlites were yellow new bulbs halgon up-grade were only getting like 9.5 volts to them )


If you want really bright lites , its best to put a relay in the circuit. try this , after you check your voltage going to the lites an cleaned the term.,,, get you a long jumper wire an go right from the battery postive post. to the back of the lite low beam side . an look at the diff. in the brightness of the 2 lites , the one with the jumper will be at least 50 to 100 % brighter. ( this is only a tempory thing for the test ) If you like the diff , I'll try an send you the wiring diagram on how to put a relay in the circuit to make the lites get full voltage.

I do this to all my vechiles an my 3 boys vechiles as well , it makes your low beam lites as bright as most high beams , an if you live out in the country it really is a safety issue , with the deers an hogs , an other animals running around. An never have had a problem , the lites dont burn out any quicker , etc

 

I don't know a whole hell of alot about electrical lighting problems in older vehicles. I do know that a 12 volt low beam uses 12 volts and whatever amperage the lamp is rated to, just like a 12 volt high beam uses 12 volts/amp rating. They both depend on available current. I would check the voltage at your lamp connectors as opposed to whats available across the battery terminals while the truck is running. Check the battery to body ground. If you're getting 9 or 10 volts at the terminals, you do need some electrical work. A relay type system like Ramrod48 suggested would do great to bypass an electrical problem in the truck as long as you do it exactly to the instructions in whatever kit you get. I'd suspect the improvement gained could be done somewhat easily in repairing the original problem. I can't say I agree with making low beams as bright as high beams since I commute in the early AM and late pm. I hate nothing more than high beams oncoming or in my rear view. On a country rd with little traffic I'd love it. Original performance is best but it's up to you and what you think is best for your driving conditions. Get the most from aiming your lights and being sure the electrical system is up to par.

It also wouldn't be the first time someone has purchased a weak alternator. Voltage across the battery terminals with engine running, loads on (lights and blower motor on high) should be roughly 14.0 volts. If it isn't, I'd take it back to the parts store.

 

My personal favorite is the guy coming at you with one headlite pointed up into the trees ( coon hunting I suppose ), an the other pointed rite at you , . Knowing they cant see S*#T ., whats that ole song I wear my sunglasses at nite !!!!!!!!!!!!, Happy Turkey Day Folk's............JIM

 

Ramrod: Go ahead and send me that wiring diagram if you would. Thank-you for the post!! Happy turkey day!!

 

Ok will do, I can send you aiming directions as well if you would like them ,,,,,,,,,,,JIM

 

hey ramrod48 got one customer .my headlight are pointed up and everyone is flashing there lights at me ,they were pointing up ,they put about 400 pounds af sand bags in the trunk of the car for more traction ,,that will do it

 

ich, bright headlights. no comment until you blind me. =p
(my high beams are brighter than any '76-'99 hi or low beams. Time for ya big boys to show some love. =p)

 

I saw a kit offered at dfuser.com. What it does is rewire the system. It will use your headlight signal to fire a relay with direct battery power. I jumped mine to see what happens and my truck is a 01. They got brighter. I have 100watt bulbs also. Like any transfer of energy, there is a loss in the distance it travels. I like to mess with wireing so I'm going to build my own.