1981 90 hp rude random misfire (e90tlcim)

[81_chapparel194]

~~ok I have a sporatic/random misfire on number 4 coil (not that the position matters) I swapped this coil with #2 coil and still had a misfire on the 4 coil. my question I guess is what pulses or fires the coil? its not a dead skip as sometimes it fires sometimes not. but I will say it fires more times than not. i checked the fire with an inductive timing light. all 3 other coils never missed a beat.

 

[Bosunsmate]

timing base or powerpack
check timing base with a multimeter, if thats ok suspect powerpack, if thats the two powerpack motor, swap them over like you did with the coils
http://issuu.com/cdielectronics/docs/troubleshootingguide

 

[emdsapmgr]

Follow Bosun's recommendation: That engine has two identical power packs, one for firing each head. Swap them. If the "no spark" condition moves to the other head, replace the bad power pack.

 

[81_chapparel194]

it was the stator.. it had several cracks and was oozing black "tar" from the cracks.. runs so smooth now and fires up on bump of key.