weak spark problems

[basspirate]

i have a 78 evinrude 140 i'm getting a very weak spark using a spark tester set to about 5/16. if i go to 7/16 as recommended i loose the spark. my timer base is putting out .5 volts, my stator is putting out out 150 volts but the powerpacks are only putting out about 110 volts. both powerpacks are new. i checked the grounds on the powerpacks and the grounds are good. could it be possible the grounds on the coils are bad and that would cause a voltage drop or is there something else it could be? also i tried disconnecting the shutoff wires and it did not change the problem

 

[Barnacle_Bill]

Re: weak spark problems

When testing is the starter turning at full speed? It must turn the engine over at least 300 RPM.

 

[basspirate]

Re: weak spark problems

the starter is turning at full speed. i found the kill switch to cause part of my problem cause after disconnecting it i got a good spark on one bank but the other bank is still weak. i have to wait till morning to get a new one, but any ideas on why i would still get a weak spark on one bank

 

[emdsapmgr]

Re: weak spark problems

That engine has two power packs, one for each head. Switch them. If the weak spark problem moves to the other bank, replace the bad pack.