85 HP Nightmare

[ThundariousX]

Hello this should be interesting, Im a Marine Mechanic and have been for 13 years. I have fixed/rebuilt/diagnosed every model of OMC and Merc there is.. andddd against my better judgment, let my brother bring in his friends 85 hp Chrysler Force (1989) its a 3 cyl pos with 2 pwr packs.

We have no spark in the 3rd cyl, originally the trigger failed the ohms test so we replaced it.. however we still have no spark in the 3rd.. my problem has to do with the wiring. The diagram tells me that there is (2) harness's comming out of the stator, both with a blue and a yellow wire. The first connects with the power pack running cyl's 1 and 2. According to that diagram, the other (blue) wire has to connect with the other (blue) wire rather than run into its connector. While the yellow runs to cyl #3.. really confusing, considering a 4 cyl uses the exact same set up.. except the trigger has wiring for the 4th cyl.. basicly.. im lost and havnt got all the time in the world to finish this favour, was wondering if any of you had any experience with this issue of no spark in cyl #3

 

[Frank Acampora]

Re: 85 HP Nightmare

Simple, really! Each yellow and blue wire is a pair of A/C wires coming from the stator to charge the capacitors in one box. Each half of the box uses one wire to charge itself. Since the second set of blue and yellow wires only charges one half of the CD box, the blue is unused, the wire can't be left just dangling, and the A/C must go somewhere, so they pair it with the other blue. Since the 4 cylinder uses both halves of the second box, the second blue wire is used and not connected to the first.

If you have no spark on the 3 rd cylinder, and you suspect the CD box is bad (since you already replaced the trigger) then simply change boxes. Now if the 3rd has spark and either 1 or 2 does not, then the yellow powered half of the CD box IS bad. Replace the boxes in their original position and disconnect the current half of the CD box. Rewire the second unused half in. Since it was never used, it should be good. You should have spark now.

AND: the grounding on that system was regressive. It only had one thin black wire connecting the electronic mounting plate to the bypass cover; everything was grounded to the mounting plate. Daisy-chain a ground wire from each coil and each CD box and run it around to the ground terminal on the starter side terminal strip. It will be much more reliable.

 

[ThundariousX]

Re: 85 HP Nightmare

After closer inspection, turns out the trigger wires do not correspond with the correct colors. All my wire charts tell me that all 3 sets of wires have to be both green and orange, and here i am sitting with a green/white and a red, so its powering the wrong side of the pack and triggering the other side.. so some quick rewiring and splicing and voila. Thank you for the advice Frank you know ur force.. personally I like the way they run.. but dont like em so much when they arnt running lol, Merc - OMC , they are my groove and I think ill stick to what ive mastered. Good luck guys n gals, ill see if I can help with some of the other posts