Vacuum system on 1969???
Thread Starter
Burning Brakes
Joined: Aug 2008
Posts: 845
Likes: 12
From: LAKE BARRINGTON IL
Vacuum system on 1969???
OK! So I swapped engines and now am having issues with the vacumm lines...from the interior ( I believe) 
the AIM does not have a very good layout...
I pulled the dash off previous and swapped speedos and tach.
all was working before pulled....now nothing is moving...
HOw does this thing get vacuum? does the car have to be running/on?
Thanks,
Ron
the AIM does not have a very good layout...
I pulled the dash off previous and swapped speedos and tach.
all was working before pulled....now nothing is moving...
HOw does this thing get vacuum? does the car have to be running/on?
Thanks,
Ron
Team Owner
Joined: Sep 2006
Posts: 31,267
Likes: 4,362
From: Westminster Maryland
Hi Ron,
The engine is the source of the vacuum except for that stored in the vacuum tank on the left side apron. If hoses have been removed the engine must be started to restore the vacuum need to open the wiper and headlight doors.
The vacuum supply is from the fitting in the intake manifold right behind the carburetor. The rubber hose goes through a white plastic filter and then into a grey metal check valve.
2 hoses come out of the valve, a large hose which is the supply for the actuators, and a small which is the supply for the control side of the system, the switches and relays. It doesn't leave the engine compartment.
The small hose enters the interior through a 3 hole grommet in the firewall towards the right and slightly below the level of the master cylinder.
It runs to a T near the solenoid mounted to the rear of the tach. It then continues on to the switches and vacuum overrides.
Regards,
Alan
Willcox has good vacuum diagrams and so does the AIM.
The engine is the source of the vacuum except for that stored in the vacuum tank on the left side apron. If hoses have been removed the engine must be started to restore the vacuum need to open the wiper and headlight doors.
The vacuum supply is from the fitting in the intake manifold right behind the carburetor. The rubber hose goes through a white plastic filter and then into a grey metal check valve.
2 hoses come out of the valve, a large hose which is the supply for the actuators, and a small which is the supply for the control side of the system, the switches and relays. It doesn't leave the engine compartment.
The small hose enters the interior through a 3 hole grommet in the firewall towards the right and slightly below the level of the master cylinder.
It runs to a T near the solenoid mounted to the rear of the tach. It then continues on to the switches and vacuum overrides.
Regards,
Alan
Willcox has good vacuum diagrams and so does the AIM.
Last edited by Alan 71; Mar 16, 2015 at 02:53 PM.
Thread Starter
Burning Brakes
Joined: Aug 2008
Posts: 845
Likes: 12
From: LAKE BARRINGTON IL
Hi Alan!
Figured I would repost it as a clearer question...
OK...so I do not have it hooked up to the engine!...that hose is going to the power booster!...unless I need a T hookup?
what color stripe does this rubber hose to the intake manifold have?
thanks!
R
Figured I would repost it as a clearer question...
OK...so I do not have it hooked up to the engine!...that hose is going to the power booster!...unless I need a T hookup?
what color stripe does this rubber hose to the intake manifold have?
thanks!
R
Team Owner
Joined: Sep 2006
Posts: 31,267
Likes: 4,362
From: Westminster Maryland
Hi R,
The hose for the power brakes has nothing to do with the vacuum supply hose for the headlights and wipers. It is connected to a fitting on the carb.
The supply for the vacuum systems is from a small fitting in the manifold between the carb and distributor. If it's an original hose it's white striped.
What sheet are you looking at in your 69 AIM?
Regards,
Alan
You can see the fitting in this picture.
Here you can see the single hose, the filter, the check valve, and the large and small hoses coming out of the valve. You can see the small hose passing into the interior through the firewall.
The hose for the power brakes has nothing to do with the vacuum supply hose for the headlights and wipers. It is connected to a fitting on the carb.
The supply for the vacuum systems is from a small fitting in the manifold between the carb and distributor. If it's an original hose it's white striped.
What sheet are you looking at in your 69 AIM?
Regards,
Alan
You can see the fitting in this picture.
Here you can see the single hose, the filter, the check valve, and the large and small hoses coming out of the valve. You can see the small hose passing into the interior through the firewall.
Thread Starter
Burning Brakes
Joined: Aug 2008
Posts: 845
Likes: 12
From: LAKE BARRINGTON IL
Hi alan!
Yes...i see the fitting...Zip corvette sent me a T fitting for the power brakes and vacumm hose off the manifold...?
I do not believe I have those check valves...will look...
Thanks,
Ron
Yes...i see the fitting...Zip corvette sent me a T fitting for the power brakes and vacumm hose off the manifold...?
I do not believe I have those check valves...will look...
Thanks,
Ron
Thread Starter
Burning Brakes
Joined: Aug 2008
Posts: 845
Likes: 12
From: LAKE BARRINGTON IL
OK! working!!!
soo....what does it mean when the engine goes to LOW idle...and the headlamps just slowly pop up? is this a precaution? when the engine revs...they go back down...
happens with the wiper door too, but not as much...
thanks,
R
soo....what does it mean when the engine goes to LOW idle...and the headlamps just slowly pop up? is this a precaution? when the engine revs...they go back down...
happens with the wiper door too, but not as much...
thanks,
R
Team Owner
Joined: Sep 2006
Posts: 31,267
Likes: 4,362
From: Westminster Maryland
Hi r,
The headlight doors and wiper door should stay where they are at low idle, any rpm, if the engine is shut off, or has been off and is started.
I don't know what to suggest except to check the hose routing again, the operation of the check valve, and then the operation of the switches and relays.
Regards,
Alan
Low vacuum can cause the system to act odd.
The headlight doors and wiper door should stay where they are at low idle, any rpm, if the engine is shut off, or has been off and is started.
I don't know what to suggest except to check the hose routing again, the operation of the check valve, and then the operation of the switches and relays.
Regards,
Alan
Low vacuum can cause the system to act odd.
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Thread Starter
Burning Brakes
Joined: Aug 2008
Posts: 845
Likes: 12
From: LAKE BARRINGTON IL
yeah...i think that is it...my vacuum goes down to 12 or so when at idle...
when I rev it, they return to normal...
500hp engine 454...
any idea how to check if the stock vacuum air filter or check valve are bad??
thanks!
R
when I rev it, they return to normal...
500hp engine 454...
any idea how to check if the stock vacuum air filter or check valve are bad??
thanks!
R
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