Low Vacuum Production

By the "collector outlet" I take it to be the intake manifold on the top of the engine? At this point the vacuum should be reading 22 to 24 inches of mercury and should be steady. If the reading is below 20 inches start looking for a problem. What are you reading on your vacuum gauge?

Thanks for the answers. I'm measuring the vacuum at the collector outlet, my engine is the standard. The impression is a bit of a vacuum to move or change its system, but it can be just an impression. Do you have the correct PSI value that should be coming out of the collector?

Hi Fleibel, First are you running a standard or S/C engine? What are you considering "low vacuum"?

First item would be to disconnect the shifting and the windshield wipers from the intake manifold and hook up just the vacuum gauge to the manifold to make sure there isn't a vacuum leak in one of those systems and the engine actually has low vacuum.

Let us know what you find.
JIm

How are you determining this low vacuum? You might start by checking all the vacuum lines to all the vacuum items like the shifting solenoid on the side of the transmission and the windshield wipers. Thos suction lines are the only items vacuum is used for so it will be easy compared to any modern car these days.


Gary Parsons

Good Morning, I am finishing the restoration of my Cord 810 sedan, the engine after 50 years stopped is apparently running very well. We are finalizing the assembly of the gearbox and we notice a low vacuum production by the engine. Has anyone had this problem and imagine what may be happening?