Vacuum system suggestions
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From: Senoia GA
Vacuum system suggestions
PO removed the A.I.R. Pump as well as the compressor from my '76. So which route would be best to get heat/AC systems back to operational status. Are there other systems to retrofit that would use an electric compressor to operate system rather than AIR pump. Not sure the operational condition of fan motor and various vacuum air lines. Would prefer that system would work as it should but $$$ may be determining factor. Any suggestions.
Last edited by Higgy76; Jul 1, 2013 at 07:25 AM. Reason: Added year
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From: Oxford MA-----You just lost the game!!!!
The A.I.R. pump (AKA the "smog pump") is/was purely an emissions control gadget. It has nothing to do with ac or heating. As far as the ac goes, well, you'll basically need to replace what's missing, and that's hard for any of us to tell over the internet, if you see what I mean. Unless you are thinking about an aftermarket ac setup, which I know nothing about.
Scott
Scott
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From: mount holly NC
2025 c3 ('74-'82) of the Year Finalist - Unmodified
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From: Oxford MA-----You just lost the game!!!!
This is another good article about how the headlight system works:
http://forums.corvetteforum.com/c3-t...tem-works.html
The vacuum operated accessories on a C3 'vette are not limited to the headlights, either: the heater and A/C controls, wiper door on '68-'72 'vettes, etc. are operated using engine vacuum. It actually is not technically correct to say that these things are "operated" by engine vacuum, the vacuum is used as a signal, or trigger, atmospheric pressure is what actually operates the accessories, as in the low pressure area created by exposing a certain component to engine vacuum allows atmospheric pressure to move it, also known as "differential pressure". It would serve you well to learn a little bit about how differential pressure works, as your carburetor uses this principle to operate, also.
It sounds like you have no idea how the whole thing works right now, so if you study the links provided, and it still doesn't make any sense to you, don't be afraid to come back and ask dumb questions until it does. I have asked more than my share of "dumb questions" on this forum, that's for sure!
Scott
http://forums.corvetteforum.com/c3-t...tem-works.html
The vacuum operated accessories on a C3 'vette are not limited to the headlights, either: the heater and A/C controls, wiper door on '68-'72 'vettes, etc. are operated using engine vacuum. It actually is not technically correct to say that these things are "operated" by engine vacuum, the vacuum is used as a signal, or trigger, atmospheric pressure is what actually operates the accessories, as in the low pressure area created by exposing a certain component to engine vacuum allows atmospheric pressure to move it, also known as "differential pressure". It would serve you well to learn a little bit about how differential pressure works, as your carburetor uses this principle to operate, also.
It sounds like you have no idea how the whole thing works right now, so if you study the links provided, and it still doesn't make any sense to you, don't be afraid to come back and ask dumb questions until it does. I have asked more than my share of "dumb questions" on this forum, that's for sure!
Scott
Last edited by scottyp99; Jul 1, 2013 at 11:45 AM.
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From: Senoia GA
Thanks for the info. I'm glad I'm finding out what I don't know now, otherwise I likely would have been discouraged, but its just a indescribably nice looking car and still glad I have one. Just have to get educated. Thanks again for the links.
Higgy09
Higgy09
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As mentioned above, the headlights etc. operates by vacuum provided by the the intake manifold.
The A.I.R. pump compresses a small volume of air slightly above ambient pressure and injects it under certain engine operating conditions directly into the exhaust manifold . The oxygen in this fresh air, plus the residual heat of combustion acts to create a second 'burn' to consume any leftover fuel with the goal of reducing emissions.
It's a shame a previous owner removed the system on your car as it really does no harm. Despite all the hate and myths, the pump only consumes around 1 HP.
The A.I.R. pump compresses a small volume of air slightly above ambient pressure and injects it under certain engine operating conditions directly into the exhaust manifold . The oxygen in this fresh air, plus the residual heat of combustion acts to create a second 'burn' to consume any leftover fuel with the goal of reducing emissions.
It's a shame a previous owner removed the system on your car as it really does no harm. Despite all the hate and myths, the pump only consumes around 1 HP.
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