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electrical gremlins

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Stewart

Stewart

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Run into a weird problem today. Finally got the 73 close to being dialed in (rear throttle return spring broke so I cant sync the carbs) and now that its running like a sports car should now when I rev the engine up in gear to 5k indicated the red ignition light comes on. Shift and it goes out however it did not come on while at that rpm in 4th (Dont ask how I know)I'm pretty sure the tach may be off as it's been funky since I got the car but would the ign light glow for an over volt or just undervolt condition? At idle its putting out a healthy 14.4.

The other gremlin I've run into is with the head lights the left one in particular. It hasn't burned out but it just glows weakly and the high beam indicator is dimly glowing. High beam is also weak. Right side is fine. Any ideas
 
Alternator belt loose or diode bridge dropping at higher RPM.

Grounds on the "glowing" headlamp.

..at least that'd be where I'd start.
 
Head lights fixed. The white wire going to the marker light had been cut at somepoint by the dpo and then twisted back together. Once that was fixed properly everything is back to normal. Strangely the marker was working perfect. I cant wait till I get the new harness in so I dont have to deal with dpo fixes anymore.

Now to figure out why the alt. is going what its doing. Belt is nice and tight.
 
Hello Stewart,

the ignition warning light will light up if the alternator output voltage gets too high, does you battery area smell of sulphuric acid, a sure clue to overcharging?

Alec
 
Ditto on Piman AND belt slippage (not likely) but the other things that can be easily looked into are...

Weak/worn/bouncing brushed in the brush pack. You can yank the white plastic pack and look inside. The outer brush will always be worn more than the inner, but it still should have some length to it and it's spring should be sufficiently strong to keep the face of the brush against the contact ring on the armature.

The other thing requires removal of the unit. At very high revs it is possible to cause and "open" in the armature (stator) windings due to simple centrifugal force. You'll have to have a pro at an alternator/starter specialty shop look for that one.

BTW: When you go back together with it, use a name brand (Gates) belt that has "teeth" on the inside. They run cooler, last longer and don't have as much of a tendency to slip.

Jack
 
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