I have a 1992 Truck with a 305. It ran fine yesterday, but went to crank today to leave and it just spins. When I bought the truck, the guys I bought it from had to replace something in the distributor, not sure what it was. But the mechanic and the seller, (same person) acted like it was a common occurance in these. I did notice something, there is no popping sound when I crank it with a plug removed. I was checking for spark. The other day I did have to replace a fouled plug, and I cranked it without a plug, at popped loudly. Why not this time?I am getting no spark.

 

Got it started. It was the plugs. 2 days ago, twp plugs were soked in gas, and black. I replaced those 2 only. Today after the "no-start" episode, I pulled the two new ones and they were again black, gass/oily along wth a third plugf I found in that condition. (??) I replaced all 8, and it busted off with one key bump. What would make these three plugs like this? This motor is on its last leg by the way, just doctoring it until quits permanetly.

 

Too much fuel, weak spark (bad coil,cap,rotor or wires) Too much air(major vacuum leak)Low compression.