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i don't know how better to describe this but my 1947 Super Clipper has developed a lazy clutch. Symptoms are that when the engine is stopped the clutch pedal goes in and out without any problem. After the car has been sitting for a few days once the engine is started the clutch pedal once depressed is slow in returning until the car is driven a few miles then all seems to be back to normal. The disc is getting thin and will need replacing at some point but it doesn't slip once engaged. The car has a working Electromatic system but this occurs only with the E.Clutch deactivated. The car has the booster spring which is also adjusted as per the manual. None of my manuals has any troubleshooting information about this type of behaviour. Any ideas as to what is causing this and what the fix is?

Am wondering if the on-off solenoid valve controlling the vacuum to your EC might be leaking. If there's an easy way to totally disconnect the vacuum to EC & plug things, I'd try that and see if it still acts funny.

Edit--An easier way would be to disconnect the curved pipe in the front going to clutch cylinder and just let it hang--that would prove the same thing without worrying about plugging anything. My theory until proven otherwise, is the rubber in solenoid valve is hard and when cold, vacuum can leak but when warmed up, a seal is made.

My 47 did the same thing. But, it did not return at all. I haven't had time to diagnose the cause. In order to use the car I unhooked the cable from the clutch. It work fine that way.
Let me know if you find the cause. It might save me some time in determining what mine needs.

Thanks for the help. My suspicion is that the vacuum control is leaking also but the fact that it gets easier as the car warms makes me wonder. I will disconnect the vacuum line to the cylinder and see if I can feel any vacuum draw at the control connection. I like the novelty of the E.Clutch and use it quite regularly so would miss having it.

HH56 and 49packard, I removed the outlet pipe from the E-Cluch control valve and detected a small vacuum leak. With the pipe plugged the clutch works like it should even cold so HH56 you were right that the rubber on solenoid piston is probably the culprit. Thanks.

Well, both good and bad news. Good that you have a cause, bad because you have to fix it now. I haven't had that valve off to know exactly what's inside, but at least it looks like it can come off by itself without disturbing all your adjustments.
Hope that's a true statement. If it were my project, would undoubtedly be one screw impossible to get at without taking everything off.

HH56, One more project to keep me busy.

That's great. I'm glad yours looks easy to fix. Hopefully I will be as lucky when I finally get time to work on it.

I finally got around to looking at the Electromatic clutch control. The solenoid did come off without removing the whole assembly. The solenoid rod and vacuum shutoff piston was Ok but the little poppet valve between the inlet and the solenoid piston is jammed. I don't really even know what purpose it serves but it appears to work open and close on some pressure dufferential between vacuum and the small return spring within the unit and may have something to do with why the vacuum does not completely shut off when the E.clutch is shut off. For now I have been using the E.clutch and it works very well so maybe I will just leave it on until I get around to locating a new poppet valve.

Interesting. The book just says "the poppet is there to prevent intake manifold conditions from affecting desired normal operation".

Since, as you said, it's spring loaded to close on low vacuum, I would take that to mean lugging or something similar when you wouldn't want the clutch trying to come in when shifting or otherwise be operational. Anything resulting in low vacuum at higher speed would be ignored anyway because of the governor cut off.

Does the on-off solenoid push directly against the valve or is there some kind of seat? Looking at the cutaway, can't see how even a cocked valve would allow a vacuum leak if the regular valve is working--unless the regular valve pushes against a tilted seat--, but obviously it must.

You've piqued my curiosity so have to take one apart now.