Solex fouling plugs Q

[Geegc@aol.com]

The 1st and 4th plugs on my 68 are terribly fouled, and the engine idles the 
same with them connected or disconnected.  There is spark, however.  When 
running under open throttle, it seems fine.

We replaced the plugs, and the new 1 and 4 plugs fouled up almost immediately.

Any suggestions?

Gary C
1966 1600 
1968 2000 solex