Force 120hp 1994-1995 ignition trouble shooting issue

Joined
Jun 20, 2016
Messages
3
I have a 1994 force with the merc 4 coil single switch box ignition and experienced a no-start situation after running the engine for 1/2 hr at high speeds then some short low speed re-sets while on a fishing trip. I have determined a week or no spark outcome and have narrowed it down to (stator,Trigger,switchbox) i am leaning
towards the switch box and stator as i have a very low reading on the low speed side of the stator. I have ordered every component for the sys as i am un-certian what or if any of the components have been serviced and two reduce the chance of a failure i felt it prudent to not mix weak parts with new parts. i have done a fair amount o the motor since i bought it aside from heavy mechanical as it runs very well on plain and always started first turn and at times without use of any choke after sitting for a few months. the only part i could not get readily was the trigger assy as they are becoming hard to get up here, i am told they dont fail as often as a stator. would it be best to attempt running it with the new stator or temp providence and run the old one? its very hard to get good troubleshooting advice here and i have only been able to use manuals online and browsing the posts i see on this site. (very helpful folks i might add!)
 
Joined
Jun 20, 2016
Messages
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I forgot to add: The no start condition happened after the engine was off for 1/2hr proxy while i was enjoying some fantastic fishing i might add, thus leaving us 50 km up the shore line of a point and into the narrow way in the deepest part of the lake! this was a challenge and after a 2hr heroic ordeal with my friends 16ft alum i left it anchored off shore til the next morning when i had it towed back into the marina and has not run since. lots of force fans where their to great me i might add with some clapping and i told you so's
 

jerryjerry05

Supreme Mariner
Joined
May 7, 2008
Messages
17,923
outboardignitiondotcom has the test procedures.

​How did you determine the stator/trigger/switchbox was bad?
The chance of all going bad is slim to none.
Just changing parts might fix the problem but you'll never know the real problem.

The Mercury trigger is usually a no problem unit.
The stator and CDI can both go????

Do a spark and compression test.
Check the flywheel key.


Where's "up there"??
 
Joined
Jun 20, 2016
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hi jerry, i am in northern alberta (grande prairie) compression is decent, key way good. spark very speratic and weak. With a small plug that i could open thie gap on i was able to see a more spark not much more then a little lawn mower puts out and more white then blue. i also removed the plugs and re-tested it did increase but not much still little or none on the boats standard plug. i am just very worried about finding another failed component on the water that is why i decided to change all three to start and the trigger is my hold up boat parts supply is limmited and i having two wait three weeks for del on part so thats why i am wondering if i should temp providence and run this old trigger? merc says change components together to eliminate fatigue on the new and used ones and others have told me ignore that. i may just re-install it and order in the new one as a spare. from what i have read and herd they normally fail most always from a broken or chaffed wire?
i also hate hearing (i told you not to buy that! ha) so i am making certian my suzuki four stroke neighbor does not get another oportunity to grind it in! i have learned alot and being as i come from a low income family i learned to fix as much as i could this old malibu was a good deal but i dont think it was not cared for very well. if re-install that trigger and she thunders this weekend i will let you know. i am anxious to get out on the water the old 120 gives these new four strokes a challenge and you can tell it does not sit well with the competition. i feel this old engine has life in her that also is my down fall i hate giving up on something. if you have any re-assembly pointers ie; carb kit, fuel pump, flywheel i would be very happy to hear them.

Thanks again! you folks got me farther on this site then my local merc dealers!
 

jerryjerry05

Supreme Mariner
Joined
May 7, 2008
Messages
17,923
Mercury suggested replacing all the parts to eliminate fatigue.
​They also make a ton of $$$ on parts.

Broken/chaffed wire: do a complete inspection and replace all the connectors that look questionable.
Mercury's plug in connectors has always been a bad spot (my opinion)
They arc and turn black and eventually fail.

Sounds like the Sasucki is way newer.
Wait till he has to buy a part for his motor.

Compression: actual #s??
Get an inline spark tester. Here they're fairly cheap but there probably not.
But the results are worth every penny.
 
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