Mercury 85hp running bad

Question
Ron,
 Last year I got a free 15ft. Glastron boat with a 1976 Mercury 85hp outboard on it.  After cleaning the engine up the boat ran well for about a month.  Then all of a sudden we couldn't get any power to pull up skiers or much to even get around the lake.  We let it go for the winter and I'm trying to get it going again.  We can get it to run great when it's idleing.  But as soon as we put it in gear to go forward...the engine bogs down and often dies.  Please give me any advice that you can.  We'd love to get out on the water soon.  Thanks

Answer
Hi Bryan - Thanks for sharing your concern with me. I'm not a master marine mechanic, however, there could be a single problem or multiple problems that need trouble-shooting. First, have you filled the fuel tank with fresh gas? Old gas just won't do. I would check the fuel filter. It may be clogged and requires replacement. Secondly, check the fuel pump to ensure it's full. The diaphram may be damaged and needs to be replaced. I'd double check the fuel line for secure connections from one apparatus to another and right to the carb or injectors. Maybe there's not be enough air mixing with the fuel, or it just needs a darn good overhaul. Best you select a reliable marine mechanic and have them diagnose the source - quickly. It could save you time and money, and get you mobile a whole lot sooner.

Safe Boating
Ron