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I am trying to diagnose a vacuum problem with my 1969 Astro Ventilation. It's a non AC coupe. Everything is fine from the metal tube to rubber connection in the centre console to the back. Vacuum holds and the louvres actuate as they should. However when I put vacuum to the supply side coming through the firewall, it either doesn't hold vacuum at all or loses it quite quickly. It gets to a maximum of 15 PSI and then drops. Does anyone have a diagram of the actual control and how the vacuum is redirected? Is there a seal or gasket in there? Aside from the Astro (I have another name for this that also starts with "A") Ventilation working, my bigger concern is draining vacuum from the rest of the system and causing issues with my wiper door and headlights
Last edited by 5869Corvette; May 12, 2020 at 12:19 PM.
I have this diagram. It's very good and helps me in understanding the system. What I need is how the actual control (the thing with the wheels on it) in the console moves the flow from one tube to the next. There are 4 usable ports on one side and 2 on the other (as per the diagram and wha's actually in the car). I'm really looking for a way to diagnose the vacuum loss between the firewall and everything that runs from this control with the exception of the back vents which I have already determined are fine. When I had the car apart I checked everything and it seemed good so my spidey sense is directing me to that control unit... but I could be wrong and am asking for wise help!
I'll look through my stuff, the only thing I know right off is the rear only gets vacuum (shuts the doors) when the control is set to heat, (that's the one on the right side two ports)
I think I labeled them when I removed mine so I'll have a look
M
So the vacuum on the right wheel only closes the rear doors when it's on heat, otherwise does nothing and they stay open
Left wheel controls vacuum to either side of the defrost door (#3 and #5 ports on the other diagram) and the AIR DOOR VALVE (#4) and the vac supply goes over to the right wheel regardless
I have the 70 Chassis Manual. Things are well explained. Figure 15 is essentially the same as your schematic above. It outlines the connections to the two vacuum switches. It's those switches that I am asking about. Can anything go wrong internally? Can leakage occur there? Thanks!
Anything is possible but it's highly unlikely it would be there, it's just a matched set of slots inside.
The big connector plug has been known to leak from distortion/tearing. I'd suggest that before the valve it's self,
If you have a hand-vac pump it would be easy to test. or get a short piece of vac hose and a couple of nipples and test the connector plug input to 3 then 4 etc
if the plug is bad you can eliminate it and connect the hoses right to the nipples on the valves
If it's the valves, I don't know that they are repairable
Hopefully Ernie sees this and maybe has something to add. Willcox has played with a lot of this stuff over the years
M
Ok... Thought I had checked all of these things separately before I put everything back together. Get it right the second time... Mityvac and I have a date in the garage! Thanks
By the way, I just noticed you are in Toronto. I am just north of the city in Cookstown. Once this weather gets better we should meet at a cruise night somewhere. I take my 58 out quite a bit. Cheers
Astro Ventilation Control
