3 cy 90hp merc has spark,wont turn over **1968 Larson restore project

I have tried everything...The engine is a 87-89 ? Mercury 90 hp 3 cy..It was running when I purchased it. At one time it would backfire but now it wont even backfire..New Plugs (correct plugs verified by 3 marinas) unpluged the wireharness and jumped the silonoid to see of that was the issue, but it wasnt? I have unplugged everything except the battery and still it will not start up. Tried WD40 shots in the carbs..notta.. What could this be? It is getting fuel to all three carbs, and getting spark, verified each plug against the block with ignition on. Althought the spark seemed dull or faint, it still should at least fire and run, correct?> ANY suggestions are welcome...Marina said it was an electrical issue (maybe coils, or stator) but if that were case I wouldnt have any spark I don't think..Compression is good, fuel is good, has spark (not sure how much spark is good?) Can you adjust the timing on OB? it has the marks on the wheel but I am not sure how to adjust it? maybe the timing is completely out??

Re: 3 cy 90hp merc has spark,wont turn over **1968 Larson restore project

If it was running when you bought it, timing did not change mysteriously and it is best you keep away from that as it is very likely not the problem. Faint spark apparently is the issue. No - faint spark means something is amiss in the ignition system Faint spark fails entirely under compression. If you have good spark and good fuel and it is getting to each cylinder it should run. WD40 should be replaced with a fuel/oil mix and sprayed into the carbs. Are the plugs wet when you pull them out. If so, you have poor/no spark. If they are dry you have a no fuel situation.

Re: 3 cy 90hp merc has spark,wont turn over **1968 Larson restore project

S-,
The plugs are wet when they are removed, and do you know of a link that would have OHM specs for the coils, stator, or board, etc.? I guess I would begin with coils, it just seems strange that anything electrical could of gone bad when it was just running..I thought the timing was a stretch, but wasnt sure why it wouldnt turn..I tried the gas and oil mix but no luck..if I flick the starter really quick and fast i can get it to backfire..Only did that twice, so I dont blow out a new problem! Thanks for the advice, I keep trying as long as you have patience!