When i purchased my car 8 years ago this was on the old intake manifold. Since then I've rebuild engine and changed lots of parts. However today while looking through my old parts I noticed this on the back of the manifold. Any ideas ??

 

36 views no takers?? Come on guys...

 

its a vacuum valve thats controlled by coolant temp, for a choke pull off maybe

 

Whats the point of it?

Why would someone want it/need it?

Would this have anything to do with Vaccum needle bouncing back and forth?

 

I don't think you need it with the air filter your running now. That vacuum switch would open or close the valve in the original air filter assembly intake neck, kinda acting like a choke so the engine would grab air from the hot exhaust manifold piping on a cold start.

But judging by your location, let me know if I should explain what "cold" is lol.

As for the bouncing needle, if all vacuum connections, and hoses are good, and there's no vacuum leak, some will say you may have a bad cylinder or some other internal damage.

From your other head gasket thread, has this motor ever been hydro-locked ? Doesn't take much to bend a connecting rod that way.

 

If I had a bad valve, it wouldn't seat properly. All valves checked out ok at the machine shop. Not sure what else it could be??

Yea I know cold. I'm from NY don't forget /)

 

That think was in the water passage though. It has some sort of temp valve on it ??

 

I think those valves were used to move a baffle in the air box so that when the engine is cold, warm air routed over the exhaust manifold is drawn from below to assist in fuel atomization in the carburetor and intake manifold. Improves cold starting performance and reduces emissions. Once the engine warms up, the vacuum valve moves the baffle to draw cooler air from the air cleaner snorkel instead.

 

Oh crap, I was just going by your "Cyprus", and after Googling it , thought you were some rich guy living in a Mediterranean Island paradise. The pic has that kinda feel to it lol.