Mysterious engine dieing...help
Sorry I haven't been on the board in quite a while. I'm in the Air Force and just moved to California, moved again and then the 11th came and finally I'm back home for a little while.
On to the problem...Been driving the 79 CJ7 w/304 and complete Team Rush upgrade with all MSD parts for about a year and a half with no problems at all. Friday it died on me 4 times just like someone cut the ignition off. The only thing different about my setup is I have the switched 12v source for the MSD box on a 30 amp switch under my dash for a little theft deterrent. This weekend I went through the entire fuel and ignition system. Nothing wrong with fuel (or air or vacuum), replaced the filters just in case. Went thru the ignition and could find no loose/frayed wires or bad grounds. Cranked it up and it ran for about 5 minutes and died. Pulled the coil wire on the distributer and checked the spark on a ground by jumpering the two pickup wires off the distributer...nothing. I had 12v going to the MSD box. Jeep sat for 2hrs while I went for parts. Came back, checked for spark and got one. Jeep cranked right up. Ran for 5 minutes, died, checked and no spark. Changed coil...checked for and got spark. Jeep cranked right up ran for 5 minutes and died...checked, no spark. Sat for 5 minutes, checked for spark again and got one.
Any clue as to what's going on? Is it a heat thing? Is my MSD box on the fritz. When the engine is running there is about 14.7 volts going into the MSD main power wire. Too much, maybe frying stuff? Any help is greatly appreciated. Like I said it's been running great for over a year and I'm very pleased with the setup.