I have 1985 50hp yamaha precision blend two stroke I took it to the river yesterday and won't go full trotle I check compression and #1 87psi #2 90psi #3 95psi I check spark and using inductive timing ligth and founded cilynder number one spark is too weak I swaped coils and the problem still in the number one cilynder ? Bad power pack maybe? Thanks please heeeeeelllpppp
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