spock345
Well-known member
- Joined
- Nov 3, 2016
- Location
- Livermore, CA
It would seem there is something wrong with the charging system on my B20F (SU carbs) and could use some input because I am unsure where to look next for the problem.
Today I was out for a drive and got stuck in traffic in the woods where it was dark enough to turn on the headlights. I notice as the car sat there idling that it would slowly get slower. Eventually I had to feather the throttle and engage the fast idle through the choke to keep the motor running. I turned off the headlights and the problem fixed itself. It wasn't all that hot both under the hood and outside, which is generally what causes issues with my SUs.
It is running a GM 63 amp alternator, the lights are Hella H4s, otherwise stock wiring. My volt gauge reads about 14 volts when nothing is running in the car. It drops to 13 initially when idling with the lights on and eventually drops to 12 and keeps going down. Turning on the high beams or auxiliary lights on accelerates this. Parking lamps don't draw enough to cause problems. The battery isn't even a year old and never been drained enough that the car wouldn't start promptly. The alternator is outputting 14.35 volts at idle and seems to be working ok.
Normally it idles in the 750-850 range depending on how hot it is out. It'll drop below 700 and then hover just above the 500 mark on my tachometer while trying to die.
I've got the car sitting so I can get a voltage reading on the battery after it has sat.
Today I was out for a drive and got stuck in traffic in the woods where it was dark enough to turn on the headlights. I notice as the car sat there idling that it would slowly get slower. Eventually I had to feather the throttle and engage the fast idle through the choke to keep the motor running. I turned off the headlights and the problem fixed itself. It wasn't all that hot both under the hood and outside, which is generally what causes issues with my SUs.
It is running a GM 63 amp alternator, the lights are Hella H4s, otherwise stock wiring. My volt gauge reads about 14 volts when nothing is running in the car. It drops to 13 initially when idling with the lights on and eventually drops to 12 and keeps going down. Turning on the high beams or auxiliary lights on accelerates this. Parking lamps don't draw enough to cause problems. The battery isn't even a year old and never been drained enough that the car wouldn't start promptly. The alternator is outputting 14.35 volts at idle and seems to be working ok.
Normally it idles in the 750-850 range depending on how hot it is out. It'll drop below 700 and then hover just above the 500 mark on my tachometer while trying to die.
I've got the car sitting so I can get a voltage reading on the battery after it has sat.
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