frustrated newbie needs help 72mercury 7.5

[tori..nogt70]

First time to post. I have a 72 mercury 75 {7.5} . the top cyl has 100 pnds compresion about the same on the lower. both cyl have spark, the motor runs on the bottom cyl. top cyl. is real gassy. could this be a fuel pump problem, reeds, this has been very frustrating and I would appreciate any help

 

[jbjennings]

Re: frustrated newbie needs help 72mercury 7.5

Just my opinion:
Your spark is weak on top. Just because it sparks in open air doesn't mean you're getting spark under pressure in the cylinder. It's gassy because you aren't igniting the fuel entering the cylinder. What color was your spark and how far a gap did it jump when you tested it? If it jumped a 7/16 inch gap and was nice and blue on the top cylinder I'd be suprised.
JBJ