Question for Joe Lucia or John DeGregory

[David Z.]

Can anyone give me the part number for a correct weight cam from a 914 dual point fuelie distributor ?

Thanks to all who read this... Dave Z.

[William C.]

Re: Question for Joe Lucia or John DeGregory

Group 2.388, P/N 1881371, same as any Chevy Passenger car of the era. The advance secret is in the springs and the shape of the cam the weight moves against.

[Joe L.]

Re: Question for Joe Lucia or John DeGregory

Can anyone give me the part number for a correct weight cam from a 914 dual point fuelie distributor ?

Thanks to all who read this... Dave Z.

Dave------


I'm not sure if you're talking about the cam/weight base or the advance weights, themselves. No matter. The weights were GM #1924737, discontinued without supercession in July, 1990.

The cam/weight base was originally GM #1941232. That part was discontinued in July, 1965 and replaced by GM #1957873. The latter was discontinued without supercession in March, 1981.

[David Z.]

Re: Question for Joe Lucia or John DeGregory

Thanks guys...now a follow up question....when the number correct part is installed correctly, would you expect there to be any play or vertical clearance between the top of the weight base and the bottom of the rotating plate (where the other ends of the springs attach) ie: should it be able to move any vertically up the distributor drive shaft? Are there any visible stamped numbers on the correct part to identify it?

Thanks again, Dave.

[William C.]

Re: Question for Joe Lucia or John DeGregory

Normally there will be some up and down movement, it's directly proportional the the clearance between the drive gear and the bottom of the distributor shaft housing.

[David Z.]

Re: Question for Joe Lucia or John DeGregory

That is why I posted the question..... I have a " correct" amount of play (7thou) between the drive gear and housing at the bottom , no shaft wobble, in fact the car is running really well... yet the weight cam and attached rotor have the ability to move up and down I would say somewhere between 1/8 and 3/16 of an inch I realize that when the weights and springs are attached it somewhat negates the ability of the rotor to move, but I just would like to know if this is normal, or the result of an incorrect part having been installed by an earlier owner.

Thanks again , Dave.

[Jerry G.]

Re: Question for Joe Lucia or John DeGregory

On FI distributors you have TWO points to shim. One is the bootom of the shaft and the other is inside the drive gear housing at the base of the gear that drives the cross shaft. Jerry

[David Z.]

Re: Question for Joe Lucia or John DeGregory

Thanks Jerry, but as I read this..shims, or lack of shims in the gear housing below the cross drive gear would only affect up and down movement of the main drive shaft and would have no bearing ( no pun intended) on the free movement of the point cam and attached weight plate which rides on the shaft above the breaker plate no?? It is the up and down free play of that, above the breaker plate, which in theory could allow the rotor to move up and down, that I am questioning. My Main drive shaft clearance is not an issue at this point.

Thanks for your patience guys.... Dave Z.

[William C.]

Re: Question for Joe Lucia or John DeGregory

Actually Dave, the situation you are seeing is not uncommon on an FI distributor, because as you can see from the attached exploded drawing, there is a thrust washer under the gear on the mainshaft of the FI distributor, so that when you are adjusting the clearance on the gear that is driven off the cam, you are really only controlling the movement between the lower gear and the cross-shaft area of the distributor. Whatever travel exists above is unchanged because of the limitations of the thrust washer working against the gear in the pump drive area of the distributor. The only way the reduce excessive travel in the upper cam would be either to install a new (unworn, taller) upper bushing in the distributor, or sneak a small shim in the underside of the weight plate to reduce any excess play. I really don't think you have a problem here, it's just a different design configuration than the standard distributor in the amount of control applied to the cam/weight base assembly.

[David Z.]

Re: Question for Joe Lucia or John DeGregory

Yes Bill you are correct...I don't see or feel any signs of this causing anything bad at all , just curious for the most part.

Many thanks to all,Dave.