I've got an 1990 140 Hp Johnson, it fired once and then it won't fire again? The compression on the bank of cylinders on the port side is 105 and the starboard is 100, this was done cold for I couldn't start it to warm it up, is it time for a rebuild? Also I did check the spark and the spark seems weak? On all the cylinders? How far should the spark jump? Is there anything else I should check? Help!!