2003 Mercury 15 hp..... Won't start!

[beenfishin]

Hi, great site, hopefully it can help me out. I recently came across a 2003 Mercury 15 hp 2-stroke, that showed little use. Bought it, took it home and tried to start it to no avail. Nice fresh gas, new plugs, and a shot of starting fluid made no difference. It has great compression, a healthy spark, but isn't even kicking over. I pulled the carb last night, it was super clean and nothing was clogged. The plugs seem to be getting plenty of fuel, so I have kinda rulled that out. Seems electrical to me, but any help would be greatly appreciated!<br /><br />Thanks!<br />Ben

 

[madmarlin]

Re: 2003 Mercury 15 hp..... Won't start!

Hi Ben, if you are getting spark on both plugs then my guess wouldn't be electrical, when you tried starting fluid was that into the carb or direct into cylinders if not try some petrol into cylinders and replace plugs and try pulling if it kicks over it must be fuel problem trace all way back to tank and and see if any probs there. Another thought I recently had prob starting my 25 and found that idle revs wasn't adjusted properly thus couldn't increase revs whils't in netural once adjusted corectly started no worries. Good Luck.

 

[beenfishin]

Re: 2003 Mercury 15 hp..... Won't start!

The starting fluid was directly into the cylinders, and didn't even cause it to sputter. I replaced the fuel line, primer bulb, and connectors to the fuel tank, everything seems fine. I've about lost hope on it and conceded to take it into the shop. I'll keep you posted on the results...<br />-Ben

 

[JB]

Re: 2003 Mercury 15 hp..... Won't start!

Howdy, BF.<br /><br />Welcome to iboats. <br /><br />Go to the Engine FAQs Forum and do the "Outboard wont start" troubleshooting. That will narrow it down to one system, then we can give you some useful advice.<br /><br />Let us know what you find, and good luck.

 

[Silvertip]

Re: 2003 Mercury 15 hp..... Won't start!

It could be the flywheel key is sheared or partially sheared which puts spark timing out of spec. Although you see healthy spark its of no use if it happens at the wrong time.

 

[Texasmark]

Re: 2003 Mercury 15 hp..... Won't start!

I think you narrowed it down to spark, unless your condition was flooding and your starting fluid just made a bad condition worse. When you shoot starting fluid directly into the cylinder and don't get as much as a wiggle, ignition is the culprit.<br /><br />But you could have a compression problem, but wouldn't expect that on a near new, slightly used engine.<br /><br />On checking the spark. Plugs can fire in air and not in the combustion chamber due to combustion pressures. So if you take the plug out and hold it against the engine while cranking, and get a spark, you won't necessarily get one when correctly installed if you have a weak spark. <br /><br />If you have a common coil, or common power pack, you could have sparking problems, but if your engine has separate ignition packs for each cylinder, both won't go bad simultaneously.<br /><br />Other thing is engine timing. If the timing is off regardless of how hot the spark is, she won't budge. You wouldn't expect timing to be off on a new engine....unless someone was dinking with it.........but timing being off could include a sheared or semisheared Woodruff key where the flywheel connects to the crank.<br /><br />Removal of the flywheel securing nut and looking down at the top of the flywheel (under where the nut was) will allow you to see that the flywheel is correctly aligned with the slot in the crank; not half sheared, or sheared. Hitting a submerged object can do this....BTDT.<br /><br />HTH,<br /><br />Mark