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77 rt side headlight stuck open

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Old Jul 4, 2013 | 10:23 PM
  #1  
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Default 77r t side headlight stuck open

hello all. brand new guy here. I have a 77 took the 350 out and put in a 383. runs good but only 9 lbs vac at idle. I don't reall care but my headlights, which were always slow wouldn't open. no problem... I,ll help em. well that worked once. now the rt side is STUCK open. lt side opens and closes with a nudge but rt side will not budge. did a search and found nothing about stuck lights. car doesn't get driven much so I don't mind helping them open/close but stuck open sucks. any thoughts?
thanks in advance
dave in north central pa.
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Old Jul 4, 2013 | 11:06 PM
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From: mount holly NC
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Pull down on this part from underneath.


The other side should not just push down, it needs an adjustment.
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Old Jul 4, 2013 | 11:10 PM
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well thank you! as I said they used to work although a mite bit slow. old motor had 14 lbs vac at idle this one has 9... that the cause???
thanx again
dave
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Old Jul 4, 2013 | 11:43 PM
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they are vacuum operated, and the 9 probably isnt enough, do you have a hose leak or off somewhere, can you adjust your idle screws to get more vacuum/?
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Old Jul 4, 2013 | 11:54 PM
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From: mount holly NC
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Many times the seal in the actuator goes bad.
You can jump to that part or go through the whole system.
http://www.corvette-101.com/vacuum.htm#top

For me getting or keeping everything working is part of pride of ownership.
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Old Jul 5, 2013 | 07:02 AM
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Is the engine only capable of producing 9" Hg, or do you think you have vacuum system leaks? If you are not sure, disconnect all the vacuum 'source' lines from the carb and intake manifold...except one, so you can hook a vacuum gauge to it. Fire the engine and adjust the carb and timing for max vacuum. Then you will know what vacuum level the engine is capable of producing. If it really is only 9" Hg, then you are on the borderline of your vacuum systems functioning.
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Old Jul 6, 2013 | 12:14 PM
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No.. I think 9 is all this combo will make. It's a new motor and I was told to expect it.... Thank you for the replies!
Dave
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Old Jul 6, 2013 | 12:38 PM
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Your lights will work with only 9 lbs. vac at idle.
I have about the same 9 lbs. with my setup. (355 with a Holly sysm. max kit 425hp)
I had a problem with mine and after looking it over I found a relay bad on mine and I bypassed it and the vac. tank and split the out on the good relay so it works both actuators. So far it has worked 8 yrs like this.
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Old Jul 6, 2013 | 06:21 PM
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i'd like them to work I will check that out. only had the car about 8 months but the lights never opened quite right. one sooner than the other.
thanks
dave
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