Packard Forum Index » Pre-War (1899-1942)

I have a wiper motor that has been rebuilt several years ago but does not work at all. The vacuum derives from the vacuum part of the fuel pump and appears to be working.
With the engine running what should the vacuum read prior to going into the vacuum motor?

Being the car sits like most collectible cars do, how can I keep the vacuum motor working after having it rebuilt?

Rick

Is the 37 vacuum source actually pump only or is it like later cars being actually manifold vacuum which just passes thru the vacuum pump on it's way to the wiper motor. As such it should be the same as manifold vacuum or roughly 18-20 inches. If it is pump only then no idea on the amount. Later pumps were there to just supply a small amount of vacuum sufficient to keep the wipers moving slowly if manifold vacuum was diminished due to engine load.

As for upkeep, there is a service counselor article issued in 49 recommending periodic lubrication of the wiper motor.https://www.packardinfo.com/xoops/html/downloads/SC/SC-VOL23NO10.pdf See no reason it couldn't apply to earlier cars. I believe instead of the Trico oil, the suggested modern replacement is vacuum pump or air tool oil.

Thank you for your information, honestly I think more like you said the vacuum does come off of the manifold and then over to the bottom of the fuel pump and from there up the fire wall to the vacuum motor. so the vacuum pump on the fuel pump must assist only.

When the weather gets warmer I will measure the vacuum pressure prior to entering the vacuum motor and if OK I'll give the vacuum oil a try. I have never serviced the motor, It makes sense things would get dried out. Thank you for leading me to the service bulletin for vacuum pumps.

Rick