Have a 79 115hp merc with a couple of problems. first of all it is cold blooded as all get out. takes a while to get going. that doesn't bother me so much, but when I get it running and get out of the nowake boyees it will not go full throttle, even with it floored. eventually it finally kicks in gear and a guy better have a hold of something as it then kicks aaaaaaaa. it does this for a while and then starts to bogg down again....if i reach back and give it a few pumps on the bulb it goes like sixty again. wish i could get this fixed and don't want somebody to take advantage of me not knowing very much about outboards. to me, i think that there is an air leak and that is what is causing the bogging down after i get going...but its that starting and it bogging down at the ramp has got me. any help would be much appreciated. thanks

You may have a leaking fuel bulb valve, air leak or the fuel pump may need a repair kit. I know that most of these early models have a screen at the fuel supply side of the fuel pump you might check. Good Luck

If you have never replaced or can't remember the last time you replaced all of the above and rebuilt the fuel pump, it may be time to open your wallet. Along with that, replace the thermostats. The thermostats keep your engine at the correct operating temp. If they are in the stuck open position and running too cold, particularly during the winter, the engine will constantly be running rich fouling spark plugs and even making troubles worse. When replacing the fuel line/primer bulb stay away from the cheap off brand discount ones.

Have replaced bulb and lines and also lines within the motor, but haven't checked the screen. I'm a greenhorn when it comes to knowing what to do, but can fix anything if I just know what to do. Where is the thermostat located. I didn't even know there was a thermostat on outboards. Thanks, Kody

www.iboats.com has your fuel pump kit for about $12, piece of cake. I'd replace that bulb first though. If that doesn't resolve the problem, keep the old one for a spare.

has it always been a hard cold start? not sure about that particular model...if it has choke plates, make sure they are closing completely when you activate the choke.

On the 79 model merc, you have 3 carbs that feed an in-line 6 engine, The top two carbs are the ONLY ones that have a butterfly choke system, the bottom carb does not have any type of choke system. The faster you can crank the engine, the faster you will start. They make a starter for the 150 merc, that is stronger and faster and Bolts right on. Also make sure your battery is both hot and fresh. Old pooped batteries don't do well on that style engine. You have a distributator style ignition that runs a electronic switch box that is located in front of the carbs on the engine shroud. Check the one and only coil for corrision. Pull the distributator cap off and clean the terminals inside where the rotor turns. and also clean the rotor. WORD OF CAUTION; DO NOT REMOVE ROTOR FROM SHAFT, IT IS MOLDED TO SHAFT, REMOVAL FROM SHAFT WILL DESTROY ROTOR. Big $$$. Remove and replace spark plugs with a surface gap style plug and only a surface gap style plug. Prefer no Champion plug, use NGK instead. Lastly re adjust your carbs. Air/fuel mixture screw, 1.5 to 1.75 turns out. P.S. there is NO thermostat in the inline 6 engines...never has been. Cold nature engine is right, it's one of those things that you just have to live with, However, If you run plus fuel, it will help, and I trully believe your fowling a plug when ideling. You can raise your fast lever handle and BLOW the cylinder clean........

Listen to Mike I couldn't said it any better only other thing I would add would be there are plastic bleed restritors behind the tranfer covers and what they do is regulate the puddle fuel that puddles in the ports and if they are gone it will load up and blubber out of the hole.....OPTI