Dead miss #2 cyl. fresh rebuild.

[CooperTune]

I'm busy building engines and trannys. I have a engine test stand I use to run in cam/lifters and rings. Recent build A+ block and crank .040 bore Alloy 5 port head SW 5 -07 cam single Hif 44, LCB. Waiting for owner to send me his dizzy with Pertronics I ran this one in on my dizzy. Once run in I pulled the unit from test stand and installed in car. A couple of weeks passed and when his dizzy showed up I installed it and cranked the car. It started right up and ran but was clear it had a miss. I pulled plug wires and only #2 made no diff. New plugs, new cap, rotor and wires. I moved two plugs no change, I moved two wires no change. Changed cap and rotor still no change. Checked compression 190 across. I removed the magnet ring turned and replaced it and the dead cyl followed. It was plain the unit had been in service for quite awhile. Having never run into this before thought I would share. New unit on the way. Steve (CTR)

[mk1]

Did you try a new cap & leads?

I can't imagine anything in the unit causing that.

Very odd though.

[CooperTune]

Having run the engine for 20 plus min. at 2500 to 2000 I knew what the oil pressure, water temp and O2 were. The only thing changed was the dizzy. That included his new cap wires and rotor as well as a uesd Pertronics unit and the reluctor ring looked like it was dragging/rubbing the unit at some time. I checked for fire at plug , none. Checked at cap still none. changed everything but dizzy body and pertronics. Still no fire on two. It seems to me one magnet is not strong enough to trigger the unit. I held a small screw driver to the magnets and it seemed one pulled less no science just dangled it and turned the unit. Ordered a new unit and loaned my test stand dizzy. Wrong curve but does not miss. Steve (CTR)

[mk1]

Very interesting!

Does sound like a duff magnet doesn't it.