1968 fj40 lights dim when not on the gas (1 Viewer)

[Tx68fj40]

Lighting dramatically decreases when I let off the gas pedal, have replaced voltage regulator but that didn't change anything... any idea?

 

[igotta40]

Does the new alternator have a smaller pulley than the previous one?

 

[red66toy]

Is this in a stock engine setup? How are the electrical connections? Grounds are all good? The lights definitely dimmerf at idle vs higher RPMs but I am wondering if your lights are not as bright as they could be to begin with? Are you getting 14v at idle at the battery? How old is the battery?

 

[Tancruiser]

Just put a brick on the skinny pedal

 

[Tx68fj40]

Y

Is this in a stock engine setup? How are the electrical connections? Grounds are all good? The lights definitely dimmerf at idle vs higher RPMs but I am wondering if your lights are not as bright as they could be to begin with? Are you getting 14v at idle at the battery? How old is the battery?

Stock engine setup, connections should be good-battery 1 year old. Will check the voltage later today

 

[Tx68fj40]

Does the new alternator have a smaller pulley than the previous one?

Unsure

 

[B y r o n]

Lighting dramatically decreases when I let off the gas pedal, have replaced voltage regulator but that didn't change anything... any idea?

Your power demand seems to be exceeding the charging output of the alternator, at least when at idle. Your options are to somehow decrease the power demand or increase the power output.

 

[ToyotaMatt]

Unsure

if you have replaced the voltage regulator with a GENUINE TOYOTA Part ONLY ,

then this will get your head lights kicking Bright again

NOS Denso / NipponDenso Alternator 3-WIRE GREEN PLUG 50 AMP 9/76-1983 Interchange Part #'s 27020-61013 / 27020-61100 / 27020-61023 - VintageTEqParts.com

NOS Denso / NipponDenso Alternator COMES WITH THE CORRECT WIDE COG BELT PULLEY 27020-61013 / 27020-61100 / 27020-61023...

vintageteqparts.com

NOS OEM Genuine TOYOTA Parts Maker NipponDenso Voltage Regulator 27700-40010 Fits 1962 - 9/72 FJ40 , FJ55 - VintageTEqParts.com

NOS OEM Genuine TOYOTA 100% PARTS NEW Parts Maker NipponDenso Voltage Regulator 27700-40010 Fits : 1962-9/72 FJ40, FJ55 3 -...

vintageteqparts.com

 

[Living in the Past]

My 68 been doing this since I bought it. Replaced the alternator once and had to put original smaller pulley on it because the voltage regulator didn't like larger pulley and fluctuated all over the place any over idle. Turn the heater on and it gets worse.