Running Mercury Without Wiring Harness?

Discussion in 'Bubba's Outboards' started by turtle1173, Jun 7, 2007.

  1. turtle1173

    turtle1173 New Member

    Messages:
    611
    State:
    Mayfield, KY
    Sorry to bother you all with another question.

    I've been looking at another boat that is identical to mine. It's an early '70's Starcraft Super Sport V 16fter, except the hull is in much better shape than mine. It would be a nice hull to redo the interior on.

    It has a 1974 85HP Mercury on the back. It has not been run in probably 10-15 years. The motor was supposed to have run good on it's last trip. Let me say upfront that I'm not considering getting this rig for the motor. However, if the motor could be salvaged, it would make it easier to sell than to part the motor out. Or I might possibly use it if all turns out well. The price is certainly right.

    The problem with trying out the motor is that the wiring harness is completely rotted away. I know this is a common problem among this era of Mercury's. I don't want to sink money into buying another harness without knowing some particulars about the condition of some key motor components.

    The internal harness is not in as bad of shape and I could probably rewire some of the dry rotted wires.

    I would like to be able to check for spark and possibly get a compression reading before determining whether or not to buy the harnes. Is it possible to do this without the wiring harness??

    Thanks a bunch!!
     
  2. Bubbakat

    Bubbakat New Member

    Messages:
    4,532
    State:
    McMinnvill
    It sure is shane. You can short the solenoid out to check the spark and the compression. I would remove all the plugs before turnning over so as to make sure it doesn't start until all the lines have been replaced. I know it will up the compression a little but squirt a little TCW-3 oil in each plug hole as to not score the cylinder walls because of them being dry. Or you can spray some PB blaster in each hole.
     

  3. turtle1173

    turtle1173 New Member

    Messages:
    611
    State:
    Mayfield, KY
    That's good news.

    I was thinking I might need to cross some specific wires in order to replicate the key switch being turned on.

    I think I can find where the battery cables need to hook up. I know that I can jump the solenoid to turn it over. Under normal conditions, does the key switch have to be turned 'on' to get spark?

    Anything else I need to know?

    Thanks again.
     
  4. Bubbakat

    Bubbakat New Member

    Messages:
    4,532
    State:
    McMinnvill
    I don't think so shane but I will recheck my repair manuel tomorrow morn early



    Is that 85 one of the older 850 with the lightening bolt ing.
     
  5. jim

    jim New Member

    Messages:
    2,579
    State:
    Jacksonville NC
    HAHAHAHAHAHAHAHAHAHAHAHAHAHAHAHA,stop your killing me.I cant help but laugh and let me say I an NOT laughing at anybody.Did you ever notice that every outboard motor in AMERICA "Ran good" the last time?:big_smile::lol:What we need to do is NEVER shut them off!!!!! I wonder if "Ran good until it quit" qualifies as one of PHILS oxymorons??????Cant you just rope start this bad boy???:smile2:
     
  6. Bobpaul

    Bobpaul New Member

    Messages:
    3,039
    State:
    Supply NC
    After oiling up the plug holes, just see if you can turn the flywheel by hand.

    chances are there will be no spark.

    carbs will need rebuilding.

    Expect to put at least 450.00 in parts, if you can find them. Part that rascal out and save yourself the agrivation, unless you really love a long term expensive hobby.