MF135 Spcl

[Sid Dunn]

I have 135 Special with Continental Z134 gas. The 2 and 3 cylinders plugs foul out pretty quick with dry black sooty deposits. Can run it fine with clean plugs which will last 45 minutes or longer. Normaly this indicates weak spark or rich fuel/air mixture.I checked spark from each plug boot and is good. The compression on the cylinders is #1- 131 psi, #2- 136 psi, #3-136, and #4-136psi, so everything seems ok with rings and pistons. If valves were bad it seems it would run bad all of the time, even with clean plugs. Went out today and changed plug wires and put some Marvel Mystery Oil in plug holes and will let it sit until tomorrow. If spark was weak, seems like all of plugs would foul, not just two. Any suggestions appreciated,thanks

 

[Tom-TX]

From what you have described, I would put on a new dist cap, new rotar, new points, new condensor, and new high quality plug wires on all cylinders, along with new coil wire, If no change, then new coil. Check all wiring for good conections. Tom