lower unit

Discussion in 'Bubba's Outboards' started by shadguts, Dec 18, 2007.

  1. shadguts

    shadguts New Member

    Messages:
    564
    State:
    Tennessee
    Bubba I have a 1979 100hp johnson that has 3 bad cylinders. I thought about building it but got another engine instead. I dont think the 100 is worth keeping but I hate to throw away a good lower unit. My question is how to remove it. I have removed every visible bolt and can move the lower unit from side to side and it will seperate some but refuses to come off. There were two bolts on each side and one under the trim tab. I also tried to remove the power head but same results. The head will turn but wont come off. I am sure there are no bolts left in it. I even suspended it on a cherry picker and it wont come off. I feel like Im missing something really simple. I've replaced several water pumps before with no problem. I dont have the model #. Thanks.
     
  2. BKS72

    BKS72 New Member

    Messages:
    3,361
    State:
    East of KC
    Check the shift linkage. There is a 1/4" bolt that holds the linkage onto the shift rod on the back side of the motor way up under the engine block. It's a bear to get to and you may have to watch it while somebody moves the throttle to see it, but that's what it sounds like. It could be the lower unit input shaft siezed to the crank, but if you can get some play out if it it doesn't sound like that's it. Bubba will give you the right answer in a minute, but I've forgotten that shift linkage connection before. Good Luck!

    Branden
     

  3. Bubbakat

    Bubbakat New Member

    Messages:
    4,532
    State:
    McMinnvill
    Double check all the bolts and then the shift linkage. If all that is loose then the drive shaft is seized inside the block. Those can be bugger to get out.
    If can manage it turn it upside down and squirt some PB blaster on to the shaft where it can run down it into the splines in the crank and sometimes they will give loose. You can also take some wedge blocks and come in from both directions and do it evenly and sometimes it will break it loose.
     
  4. shadguts

    shadguts New Member

    Messages:
    564
    State:
    Tennessee
    I thought that the drive shaft was seized just didn't know it could be. I completly disassembled the powerhead. I put all the parts up just in case. You are right about the shift linkage connection. It would be rough getting to with the powerhead intact. Thanks Bubba. I will try that. I know if I threw it away someone want it within a week.