That is what I found no vent, the new cap has a vent! I used this dizz out of a stocker motor and placed it in my perf.motor It like the stock but didn't do justis at the RPMs I turn it now! Thanks for the input guys! WT
This sounds goofy, but swear its true....Ford motor Co, in the mid '80's used dielectric silicone on the lugs under the cap (just a tad) to have a capacitive effect, it made the spark "jump" less and cured there premature rotor failures, which was killing those "Dura Spark" modules mounted on the fender of every POS they built (yeah, had a 1983 F150 ).
Depending on how often this is happening to you, use some electrical contact cleaner inside the cap once in a while.
Something very seldom thought of also, don't mix and match caps and rotors, sometimes the lugs are aluminum and most of the rotor contacts are brass, one will win, make sure they are of the same material.
Thanks for the info. GT I replaced the cap and rotor with new MSD! Woo Hoo problem solved at least for now! But that grease (AKA D.S.) is good to know for future reference! I was also told to use either a Cap A Dapt or a Pro Cap to spread the terminals and this would help! WT