Vacuum system HELP! Here we go again!
Thread Starter
Safety Car
Joined: Oct 2006
Posts: 3,993
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From: Gig Harbor WA
Vacuum system HELP! Here we go again!
Well, I have moved on to the vac system, neither my headlights nor wiper door are working...dead.
I have the vacuum troubleshooting guide, and have been trying to work thru it, though its a little confusing to me.
So I have around 15" vacuum at the manifold, thru the filter, and on the "large" side of the check valve. On the "small" side of the check valve (going into the dash and override valves, etc) I only have about 5" of vacuum. The check valve is clear, I can blow thru it.
I havent taken the dash out yet, so access to the headlite switch, and the T down there is pretty limited.
There is good vacuum going into the vacuum tank, and the tank is holding vacuum, according to the test in the troubleshooting guide.
There is NO VACUUM at the headlite actuators. All hoses (original I think) look fine, all connections are tight and the system is correct according to my diagram.
Any suggestions as to where to go on this??
Thanks!
I have the vacuum troubleshooting guide, and have been trying to work thru it, though its a little confusing to me.
So I have around 15" vacuum at the manifold, thru the filter, and on the "large" side of the check valve. On the "small" side of the check valve (going into the dash and override valves, etc) I only have about 5" of vacuum. The check valve is clear, I can blow thru it.
I havent taken the dash out yet, so access to the headlite switch, and the T down there is pretty limited.
There is good vacuum going into the vacuum tank, and the tank is holding vacuum, according to the test in the troubleshooting guide.
There is NO VACUUM at the headlite actuators. All hoses (original I think) look fine, all connections are tight and the system is correct according to my diagram.
Any suggestions as to where to go on this??
Thanks!
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Thread Starter
Safety Car
Joined: Oct 2006
Posts: 3,993
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From: Gig Harbor WA
Race Director
Joined: May 2006
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From: Dayton, Ohio
So you have vacuum going into the tank but nothing coming out?
Thread Starter
Safety Car
Joined: Oct 2006
Posts: 3,993
Likes: 9
From: Gig Harbor WA
Yup..But according to the trouble guide, I tested the reservoir by removing the two hoses that go from the tank to the actuators, plugged one of the outlets on the reservoir and tested the other outlet. Got 15" (my reference number). Supposedly thats a good test for the reservoir. But with everything hooked up and the car running, headlite switch OFF and override valve pushed IN, I get NO vacuum at all at the headlite actuators. I even tried to isolate the wiper side of things by plugging the input hose on the wiper override switch.
Thread Starter
Safety Car
Joined: Oct 2006
Posts: 3,993
Likes: 9
From: Gig Harbor WA
My hoses are pretty old and faded, which ones are the yellow ones (I could probably hit them with some Simple Green and figure out the colors!)? Do they connect into the middle position on the actuator?
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From: Dayton, Ohio
Thread Starter
Safety Car
Joined: Oct 2006
Posts: 3,993
Likes: 9
From: Gig Harbor WA
The check valve IS working properly as far as one way flow!! The small port definitely has a lower reading than the larger one. The large port vac reading IS the same as the one port side. Initially I got NO flow thru the small port, but cleaned it out and now it flows. It may be bad, due to the different vacuum readings.
Thread Starter
Safety Car
Joined: Oct 2006
Posts: 3,993
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From: Gig Harbor WA
Actually thats what I was thinking as well. I need to totally isolate the wiper portion. Looks like the place to do that is at the T connection under the drivers side dash?? Any other suggestions as to a more accessible place?
Race Director
Joined: May 2006
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From: Dayton, Ohio
I think you should focus on the large hoses they are your real vacuum----the small hoses are just triggers for up and down-just like a light switch---the large hoses are the POWER that makes things work.
Thread Starter
Safety Car
Joined: Oct 2006
Posts: 3,993
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From: Gig Harbor WA
but will reattack tomorrow!!!