Classic/Antique Car Repair: 235 1955 Chevy Engine, Rough running 235 Chevy

Question
I've installed this engine (supposedly was rebuilt) in my 49 Chevy.  The engine is running a little rough.  When I take off the 3rd or 4th spark plug wires, there is no change in the way the engine idles.  I've changes plugs and wires.  No difference.  I have a new distributor cap.  When I took the cap off after then engine has idled for several minutes several times over the last few days, there was "gold" flakes/particles in the area where the points and condenser are.  What does this indicate?  Could this be the reason I'm having trouble with the spark?  Any ideas of what I can try next?

Thanks.

Michael


Answer
The metal particles are brass, coming from an interference between the rotor and the terminals on the distributor cap.  Either the distributor is not assembled correctly, or there are some incorrect parts.  This is a serious problem that needs to be corrected before the engine is run again - take the distributor cap off and see where you can find signs of the rotor hitting the cap terminals.

Whether or not this is the cause of the rough running remains to be seen, but fix this first, then see how it runs.

If it still runs rough, post a follow up to me and I'll see if I can lead you to the reason.

Dick