1985 115hp mariner wont fire on any cylinder

[jpem2010]

Hy i have a 1986 model 115 stack 6 mariner that has just stoped firing on all cylinders. It has been running fine and cranking fine every time untill the other day. I usealy crank it once a week and let it run but sunday it wouldnt hit a lick and hasnt since. Ive checked the kill switch and unplugged the main harness to see if i had wiring isues in the boat but no luck. I could realy use some addvise as what to check for next. It seems like maybe the coils might be grounded out idk what wires to check that theory out. Any help would be greatly apritiated .. Thanks

 

[jpem2010]

Re: 1985 115hp mariner wont fire on any cylinder

What is the black and yellow wires for on the power packs are they the grounding wires to kill the power to the coils. Ive been reading other postings trying to figure out my problem im new to this ive never owned or worked on a mercury.. Lol luv the evinrudes

 

[ajgraz]

Re: 1985 115hp mariner wont fire on any cylinder

Black/yellow wires at the powerpack(s) (aka switchboxes) are kill wires. If they have a path to ground, the voltage created by the stator will go to ground instead of being routed through the switchboxes to the coils.

If those kill wires are NOT grounded out and it is getting no spark at any cylinder (have you actually checked for spark at the plugs?) then I would suspect a bad stator (or bad wiring from the stator), particularly the low speed windings. Do you have an ohmmeter...and just as importantly, a DVA adapter?

 

[CharlieB]

Re: 1985 115hp mariner wont fire on any cylinder

Remember there is NO RETURN on electrical parts so do NOT assume that the stator is bad without PROVING the fault.

CDIElectronics has an excellent and FREE, Ignition Troubleshooting Guide that covers all year and all outboard models.

It is posted in one of the 'Stickies', sorry I don't have that link handy.

A DVA meter or DVA adaptor to use with any Volt/Ohm meter will enable you to determine exactly what is wrong so you can order only what you need without the hassle and expense of replacing one part at a time until it finally works.

Keep posting your questions as well as your progress so we can be sure you get it running fine soon.

 

[jpem2010]

Re: 1985 115hp mariner wont fire on any cylinder

Thanks for the info i did check each plug wire and it doesnt have any spark. My next question is can i unplug the black and yellow wires and see if it will fire or will that mess anything up. Just wondering cause i dont have a ohm or voltmeter at this moment.

 

[Chris1956]

Re: 1985 115hp mariner wont fire on any cylinder

Yes, unplug the black/yellow wires at the Switchboxes and see if spark returns. If so, those wires are grounding somewhere. Ign keyswitch and lanyard kill switch are two likely culprits.

 

[jpem2010]

Re: 1985 115hp mariner wont fire on any cylinder

Thanks ill try that and see what happens.

 

[jpem2010]

Re: 1985 115hp mariner wont fire on any cylinder

I just tried it and still no fire so what mite i try next? Maybe change out the stator if so should i change the trigger and rectifier also.

 

[Dave1027]

Re: 1985 115hp mariner wont fire on any cylinder

It would better to troubleshoot to find where the problem is than to throw parts at it.

First try disconnecting the rectifier. If you then get spark then the rectifier is bad.
Check the wiring from the stator and trigger. Check for corrosion or broken wires. Check and clean all connections. If that all fails then it's time to begin testing the trigger and stator. After that pull the flywheel.

 

[jpem2010]

Re: 1985 115hp mariner wont fire on any cylinder

Ok ill try that tomorrow thanks alot i realy apritiate all of yalls advise.

 

[jpem2010]

Re: 1985 115hp mariner wont fire on any cylinder

Well i disconected the rectifier and still nothing so i pulled the stator and ordered new one ill let yall know tuesday if i get it running and i will definatly invest in a olm meter next time . Thanks to all who gave me advise yall r some great folks.

 

[quicktach]

Re: 1985 115hp mariner wont fire on any cylinder

Well i disconected the rectifier and still nothing so i pulled the stator and ordered new one ill let yall know tuesday if i get it running and i will definatly invest in a olm meter next time . Thanks to all who gave me advise yall r some great folks.

Keep us all posted on how you make out with the problem. Electrical problems require very careful troubleshooting. You got advice from Charlie B. about reading the CDI Troubleshooting Guide. It's good - and good advice. Also get a basic Seldoc manual and spend some time thinking about the problem. A good autoranging digital VOM is a good investment as a tool. A DVA adapter is a good investment too ...if you're going to get into this type of problem solving. It's solvable ...but it takes time...

 

[CharlieB]

Re: 1985 115hp mariner wont fire on any cylinder

Since you have that stator off you can bench test it using a 12 V battery and a test light to determine if it is at fault.

Connect one side of the battery to one blue wire, the test light to the other blue wire and to the battery, if the light stays on the blue circuit is good.

Repeat test one the red wires, then repeat again on the yellow.


If the rectifier burnt thru the diode(s) it sometimes leave a path for current to feedback thru the charging circuit, turning it into heating coils which can 'cook' the stator.

Test the rectifier, disconnect all wires, use an Ohm meter from one yellow to the red, note your reading. Test the other yellow to red, hopefully you get the same reading. Now reverse your leads and again test each yellow to the red. You should get a continuity reading only one direction, and none when the leads are reversed.

 

[jpem2010]

Re: 1985 115hp mariner wont fire on any cylinder

I want to thank all of yall for yalls advise. I bench tested the stator like yall told me and it was bad. I have installed a new one and is running great now thanks again. I would recomend this site to anyone who is not a pro and looking for help.