eastshores
Recruit
- Joined
- Mar 4, 2006
- Messages
- 5
First, I read the FAQ and own a service manual (not from merc) for my outboard. When I first got the boat it cranked right up.. I was impressed.. becuase I guess it sat for maybe 6 months, so I did run what was old gas through it. (now I know thats a big no-no)<br /><br />We took it out on its first test run in our intercoastal waterway and immediately knew there were problems. The only way to keep it running was by every now and then choking it. This was the first time we had seen it run in gear though.<br /><br />So.. after some reading and thought, I figured it would be best to just rebuild the carbs. After talking to a local marine shop they suggested I only buy a few parts to start with, their mechanic said in most cases the carbs don't need more than the jets and a couple other parts replaced.<br /><br />My dad and I put new gas in, and I replaced some fuel line that looked bad and it cranked well at home again. Instead of opting to do the work on the carbs, we took it out to a lake. Before doing this we drained the fuel tank and replaced it with fresh gas.<br /><br />It ran pretty good, but the only way to get it to crank was to put it in throttle forward without it being in gear. I guess this added more fuel while opening the carbs? By the way, we messed around with the idle stop bolt when I felt we were idling too fast at 1300 RPM at home. We got the idle down but this new problem of cranking started.<br /><br />After a few outtings like this, I felt it was NOT safe, especially in windy conditions to try and maneuver around docks and launch ramps with other vessels. Especially considering my outboard now had a propencity to just die in gear at low speed. Reverse was out of the question.<br /><br />So we replaced the spark plugs since I felt we had been running too rich and possibly fouled them, given that we had to put the throttle forward to get it to crank. No idea if this was right, but it couldn't hurt to replace them since I don't know when it was last done.<br /><br />So we went out and tuned the carbs using the recommended procedure within the service manual. Except my dad doesn't do much for following specific instructions. He has been a car/industrial mechanic for his whole life, over 45 years, so I think he got a feel for just getting what works done. Although on my size of outboard, he has not much more experience than me. We tuned the carbs, and went back and forth between starting real well, and not being able to idle up, and having problems starting.<br /><br />Eventually things seemed to work VERY well. We were starting after 2-3 or so turns, idle was great, and we could shift into forward and reverse without stalling. We tried throttling up since that is a key part of the carbs. Presto, works great.<br /><br />We put the outside cover back on the boat running, and go to take off and it DIED! Less air with the cover on?? We finally tuned it to try and get the best result with the cover on. But that required that my father changed our timing some. When he went to do that I thought, oh god we are gonna float out here for awhile; what am I getting myself into. But, his results worked well.<br /><br />I recently read a post in the outboardrepairs that tied back to here that described having to turn the key half way and pump the key in/out 6 times (choke) then crank on a 1993 Mariner 75hp, and that apparently fixed their problem. That was for cold start which is my biggest problem at the moment. Right now mine seems to crank ok if I choke it till it sputters, then just crank. It starts slow but clears itself and then runs fine all in idle.<br /><br />And finally my question (I added everything above for the sake of anyone that has tried the above)<br /><br />Should I just try to find this happy *medium* where my outboard cranks great... and seems to run good? Or, should I be truly concerned about perfecting the engine so that it cranks like a champ cold/hot and can rev it's RPM to spec?<br /><br />I know there are several experts in here, would be interested in all of your opinions. Much thanks to your time and energy!<br /><br />- John
clean and adjust the carbs as per the manual, there are no dependable short cuts. I have work as a marine mechanic since the 50s and still use the manual on some jobs. Do it right once and you will be much happier.