[Oreo C]

Can someone explain to me how the vacuum cowl part of the hood works? Specifically the vacuum pod. Not the mechanical side which I believe is completely separate.

My issue is that my cowl won’t ever open under WOT low vacuum conditions. It’s open with the engine off. And if I push it down with the engine off it is slow to come back up. So there has to be a way for air to leak back into the vacuum pod for it to open. Do I just have a bad vacuum pod?
I have it hooked up to manifold vacuum with the cowl induction flow control valve in the line to the vacuum pod actuator. I believe this is all correct.

Thanks for any insight.

 

[DC22]

If hood flapper closes, pod should be ok(unless it won't self return).Door normally open until engine running, closed by vacuum, open [email protected] WOT.

 

[DUTCH MAX HEADWORK]

Try running it without the flow valve. I bought a repop and it didn't work no matter which way it was installed. If it works without the valve, flip it around and see if it works.

 

[LevonH]

There is a tiny hole in the bottom of the engine side of the actuator on OEM actuators. It is a vent to allow air in to open the actuator. On repros it is often missing or it gets painted over causing grief. Also make sure the connecting hose is actual vacuum hose as wwasher hose collapses under vacuum. Lastly ensure the hose is not getting pinched at the firewall when the hood closes.

 

[72soft-top]

There is a tiny hole in the bottom of the engine side of the actuator on OEM actuators. It is a vent to allow air in to open the actuator. On repros it is often missing or it gets painted over causing grief.

How big it that hole? I have a reproduction and wondering if it’s there? My door opens but very late. Wondering if a hole or larger hole would help make the cowl door more active?

 

[LevonH]

I don't have 1 here to measure. It is small though like 1/32".
Look at this one.

Goodmark GMK40332307010A Goodmark Cowl Induction Vacuum Actuators | Summit Racing

Free Shipping - Goodmark Cowl Induction Vacuum Actuators with qualifying orders of $99. Shop Cowl Induction Components at Summit Racing.

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