Evenrude mercury 9.9 would not stay started so i pulled the filter, fuel pump and carb. Blew out all hoses links and carb cleaned everything. The motor started first pull in a barrel and I ran it for 1 hour. Alternating throttling and idling for 10 minute intervals. Then I only towed it 45 minutes to the lake where it would not start at all now. Plugs are firing with correct gap as well. Any help would be appreciated.

