FishyFish Tolman Alaskan Skiff and Boat Building Forums

Having trouble finding good info ... books on the way from Amazon, but thought I'd ask here anyway.  I have a '96 Evinrude 6-hp 2-stroke kicker with super low hours (it's only old on the calendar) and am trying to change out the impeller.  I put it in fwd and disconnected the shift linkage, then removed the 3 bolts that hold the lower unit on the mid-section, and according to rumor ... my model year has a splined end on the top end of the shaft and the lower unit should just drop down.  It doesn't.  It dropped about 1/4" or so.  With "kind persuasion", I got it to drop another inch and I can see the impeller housing just fine.  There are no access plates, magic bolts under the power head to release the shaft, or anything else that I can find that might be holding things up.  Sight ... anyone know if I'm not doing something that I'm supposed to do?  For now, I sprayed WD40 up the mid-section, I think clear to the top, and am letting it soak until the books get here ... but again, hoping someone here has been there and done that... Anyone?

Thx,
Brian

You may have already looked here, but another useful source may be Leeroy's Ramblings.  He has a page devoted to your vintage of motor with notes and exploded view diagrams:

http://www.leeroysramblings.com/johnson%20_8hp.htm

... More research this morning says that yes, the issue is that the drive shaft is stuck in the crankshaft.  The method of fixing it is to thread the lower unit mounting bolts back in, but just 5 threads or so.  Hang the motor upside down with the flywheel less than an inch off the ground ... pour PB Blaster or Krol oil or similar into the mid-section deep enough to cover the splined end of the driveshaft ... let soak.  Use plastic wedges between lower unit and mid-section and moderate taps with a hammer to try to force the lower unit to separate ... repeat until this works.     I'm waiting on a response from a couple of people to verify....

bd

I can almost slide a thin piece of plastic in just above the impeller housing that the mid-section ... maybe a strike or two from one side and the other would help?  Seems like running the motor might risk damaging the splines if the drive shaft dropped out while running. 

Another observation is that shifting to reverse lets it drop a little further ... which should not happen if it's just the splines and a little oxidation holding the drive shaft in place, and now that the lower unit is down by an inch, you can move it up and down fairly easily ... with the drive shaft staying in the impeller (also a splined connection).  These things indicate some kind of a mechanical blockage that moves with the shifter.... maybe the shift rod has come apart and is catching on the side of the tube and the power head or something.  Need to lay on my back with a flashlight and poke around when I get home tonight....

I'll take pix and share what I discover as I go.  It might help the next bloke coming around the corner....


Brian

Hi Bob,

Actually ... I forgot to up date this thread.  First of all, the motor is painted all camo and I thought it was an Evinrude because I could see a big 'E' showing through the camo paint in about the right spot.  Turns out that it's a mercury ... To buy a full water pump kit, which I decided to do instead of just putting in the impeller, I had to look up the motor serial number and found that the ID plate said "mErcury Marine", not Evinrude!  Funny, eh?

Once I found it was a Merc, I got good instructions off the web and was able to finish the job.  The shift linkage attachment under the carb was what was preventing the lower unit from coming off.  It pumps water like a bandit now ... all good   The motor starts on one pull and runs strong ... which says a lot for the SeaFoam and StaBil that I used to prep it for storage almost 14 years ago....

Brian