Mercury 15 Hp firing problems

First of all let me apologize before hand I'm new to this forum and have searched my issue but have not had any luck with finding and answer. I have a late 80's or early 90's model 15 hp mercury. It has electric and pull start. I ran into this problem last year and it has me stumped. If it is cold outside, or even cool (30 degrees to 50 degrees I would say), it will not fire with the electric start. I can pull the pull rope and it will fire on about a half of pull. After it runs for a few mins to warm up, it will start with the electric start. I have charged the battery when I ran into this issue. Then I replaced the battery with a new one. Like I stated before, it will start with the pull start with no issues and starts rather easy. Now with the electric start it doesn't start as easily or quickly if you want to say. It seems to take 25-30 seconds to fire off when it does fire with the electric start. Oh and this is a new starter last year. Any help would be appreciated.

Sounds like your starter is 'dragging' (not spinning her over fast enough). If you're handy with tools, you might disassemble it, sand the commutator and lube the bearings. That's brought back to life more than one Merc starter.

Also (and maybe first) you need to check all the battery connections and solenoid (jump across it for a test) to be sure the starter is getting full voltage.

Jeff

I actually figured it out. It took a while yesterday evening. I was just starting my motor for the first time this year to get ready for some crappie fishing. Notice my kill button wasnt working on the tillar handle. Pulled off the tiller handle to get the wires out and noticied that the Yellow/Black wire had some of the insulation rubbed off and after fixing that it works every time. Best i can figure is that the wire (yellow/black) was going to ground, therefore not letting it start. all and all it seems fixed for now. might have been just luck im not sure. not getting the cables back attached and adjusted right was a pain after a few hours i got it all back on this morning and it runs like a top now. thanks.

Ah, and why was this happening ONLY on the e-starter?

Jeff

that is what has me puzzeled? Im not sure lol. But after I replaced the wires it hasnt happened again. Now I just have to adjust the carb. It seems to be running rich on me.

When you pull on the recoil start it affects the power head position with reference to the cowling because things are mounted on rubber. This might allow enough resistance in the shorted wire to allow it to start. We are talking about barely enough of a short to foul up the spark and any slight shift in the wire will make the difference.

timguy said:

When you pull on the recoil start it affects the power head position with reference to the cowling because things are mounted on rubber. This might allow enough resistance in the shorted wire to allow it to start. We are talking about barely enough of a short to foul up the spark and any slight shift in the wire will make the difference.

Click to expand...

this is what I figure! It was just enough from pulling the pull cord to shift the wire off enough so it would not ground out.

okay back to square one! I took my boat out this weekend and the morning temps where around 33-35 degrees. I had not fire to the plugs. Got all the way to the lake and it would not start. I didnt not try to pull start it. I just used my trolling motor. Could there be something that

.......we didn't consider?

kade said:

okay back to square one! I took my boat out this weekend and the morning temps where around 33-35 degrees. I had not fire to the plugs. Got all the way to the lake and it would not start. I didnt not try to pull start it. I just used my trolling motor. Could there be something that

Click to expand...

For some reason half my post got deleted.

Could it be something that is getting condinsation in itself?? When outside temps are around 50 degrees it fires up like a top.

Could be the switch box. Johnson/Evinrude call a "power pack". I have had Belgian made Mercs that acted as you describe. Please, more help from our Merc techs. Try heating it up with a hair dryer or something. See if you then get strong spark.