115 merc wont start

[Tadd_P]

I have a 1979 115 mercury "tower of power" outboard. I lost spark due to deteriated wiring that caused the trigger to go bad. I replaced all the bad wiring and the trigger. I used a spark plug tester and have excellent spark on all 6 cylinders. Also did a compression check and all 6 cylinders check 118-120 psi. I try to start the engine and get a few sputters out of her but it just wont fire up. any suggestions on what the problem might be. Ive hooked up a gas tank full of fresh gas and its still the same thing happens.

 

[Scaaty]

Re: 115 merc wont start

Do a complete link and sync again.Clams has it covered here..

http://forums.iboats.com/showthread.php?t=168855

 

[gregtobin]

Re: 115 merc wont start

Are you saying that the starter turns well and you get a few sputters but the engine won't start?

I have the same motor. I often need to move the small throttle lever back and forth some while trying to start. I hold the key in the starter position while pressing the choke button with my right hand. I can then move the throttle with my left. Strangely, it doesn't always start at the same throttle position. If I start out with a fully charged battery, I have plenty of cranking time to work through it.

If you're still not starting, make sure that the gas is getting to the carbs.

Good luck!
Greg

 

[Chris1956]

Re: 115 merc wont start

Todd, If you didn't do the link and sync after replacing the trigger, it's time to do it. If the moror sat a long time (one year plus) while it was broken, you need to clean the carbs.

Now, if you did the link and sync and the carbs are clean, are you pumping the primer bulb well? Are you choking the daylights out of the motor? How about spraying some 50::1 fuel mix into the carb throats, and cranking it over, cold start lever all the way up.

 

[Clams Canino]

Re: 115 merc wont start

Also make sure the belt is on correctly. The little nib on the dist pulley outta line up with the little nib on the intake cover when the flywheel is at about 3 degrees BTDC.

-W

 

[Scaaty]

Re: 115 merc wont start

I often need to move the small throttle lever back and forth some

Wasting energy...it aint a "pump"..only cranks the timing up for start, and they LOVE full choke, and a good solid gas bulb...