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REALLY bright lights....

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Nunyas

Nunyas

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Tonight as I was going down Briggs road 3rd gear engine braking for nearly 2 straight miles I went over a bump, and ALL of my lights got REALLY REALLY bright. The headlights went from a yellowish tinge to a REALLY bright white, and the dash lights got REALLY bright too. I noticed the engine sounded slightly different when this happened too. About a quarter mile later I hit another bump or dip, and all the lights returned to 'normal' (maybe slightly brighter than before), and the engine returned to running the way it was before too.

It kind of freaked me out when this happened, and somewhat worried about burning something out. I know there are very few locations in the wiring that can effect *everything*. So, my initial thoughts are maybe something in the wiring between the alternator and battery. Maybe the main connection junction on the starter... I'm thinking maybe the connections somewhere between those areas might be a bit dirty or possibly loose.

You guys have any suggestions for other areas to check?
 
Sounds like your voltage regulator is on its way out! PJ /ubbthreads/images/graemlins/confused.gif
 
[ QUOTE ]
Sounds like your voltage regulator is on its way out! PJ /ubbthreads/images/graemlins/confused.gif

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/ubbthreads/images/graemlins/iagree.gif
I would look into that immediately, unless you are really into replacing fried wires! /ubbthreads/images/graemlins/pukeface.gif

Bruce /ubbthreads/images/graemlins/cheers.gif
 
Same conclusion here. V-reg went wonky, it'll play havoc on the system.
 
Sounds like a voltage regulator. If this is a generator car then the lights get bright for a few minutes followed by a strange 'sweet' burning smell followed by a red light on the dash. (this story from past customers , not me of course) The generator is not the problem to begin with but will be destroyed by the regulator. If this is an alternator car then there is a different scenario. The red light does not always come on when an alternator fails.

Alan T
 
New voltage regulators under 50 bucks, change it.
 
How can it be a LBC with an alternator? Is that an oxemoran, kind of. Oh well. Where ever it is change it, it's shot.
 
Jack, the Spridgets switched to alternators in '72. I think the B's changed in '68. My '67 GT6 was the only year that they ran a generator, and the Spits went over in '71.
Jeff
 
My 72 Midget (Aug '71) has it's Lucas alternator still in it.
 
[ QUOTE ]
My 72 Midget (Aug '71) has it's Lucas alternator still in it.

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So does my '72, and my '74. All my others are generator cars.
Jeff
 
on my 74 midget my red light glows brighter with acceleration.....could this be my regulator?.....
and am i understanding that its inside my alternator
ad can be replaced?...zimmy
 
[ QUOTE ]
on my 74 midget my red light glows brighter with acceleration

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No, that's likely a loose belt.
 
no my belt is tight and motor runs fairly smooth,
alt has a small wire and a big brown wire connected..
should there be another brown also?
 
well... I ran out and ordered a Fiesta Bosche unit today... AZ is supposed to have it ready for me to pick up by Wednesday'ish.

zimmy, there might be some dirty connections between the alternator, starter, and/or battery, if the alternator belt tightness is definitely good. My car had the same symptoms (as yours) until I rewrapped (insulated) the alternator wires, cleened and recoonected the starter wires, and cleaned and reconnected the battery wires (including the ground).
 
[ QUOTE ]
on my 74 midget my red light glows brighter with acceleration.....could this be my regulator?.....
and am i understanding that its inside my alternator
ad can be replaced?...zimmy

[/ QUOTE ]
If the light gets dimmer as you rev up the engine,(it should go out just above idle) then you most likely have a problem with the alternator. If it gets brighter, then the battery is most likely bad.
 
The following is some of what I have learned from logging in over a half-million miles in MGB's with alternators. #1 All of the battery connections must be clean and tight. This includes the grounds and especially the connections at the starter. Tug on the wire with the lug and make sure the slide on terminal is tight. (If your lights suddenly get bright then most likely you have lost contact with the battery and the alternator is overcharging. Lucas alternators are 'battery sensed' meaning they must have a stable battery and connection to charge properly.)#2 Do not 'jump-off' an MG unless you are desperate. Get the best battery you can buy and install it. #3 A glowing red light (when all of the above has been addressed) usually means that one or more of the nine diodes in the rectifier is no longer a diode . I have replaced ten rectifiers to one regulator. My 1971 MGB with over 350,000 miles still has it's original alternator on it with the exception of two sets of brushes and one bearing.
I'm sure I could say more but I need to get to work......
Alan T
 
i have a new starter and battery but i do suspect a ground somewhere.....
does the solinoid need to be bolted down or grounded maybe?
also if i take it for testing can the rectifier be diagnosed easily?.....zimmy
 
MG Midgets are a little different. They have a solenoid on the firewall and seldom have a sleezy terminal problem. The rectifier can be tested easily with a VOM. Set the selector to ohms and check the polarity of the diodes. If any conduct current both ways then the rectifier is faulty.
Alan T
 
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