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vertical shaft stuck in bf8a help

S

skipdow

New member
Trying to change the exhaust tube on a Bf8a outboard that was leaking.
In the manual it appears the powerhead has to come off to change it.
not a problem except the vertical shaft WILL NOT seperate from the powerhead so I can lift the powerhead up and change the exhaust tube.
IF I ever get it apart I will of course grease that joint so its easy the next time but what do I do now?
HELP!! :confused:

 
First of all....you do not have to pull the powerhead to change the exhaust tube. You do have to pull the head. The powerhead can stay in place.

Second....what may be getting stuck is the shift shaft, which is held by a pin on the front of the motor, under the regulator/rectifier. There is a joint on the end of the shift shaft that has to be unscrewed before you can pull the lower unit off. One that note, you do not have to pull the lower unit off to remove the powerhead.

Maybe I am confused with what you are trying to do and what is wrong.

Mike
 
The bottom of the leg is already off. The shift shaft was pretty straight forward. I am following the service manual but it does not mention the vertical shaft(rotates with crank)
I wondered about just pulling the head but it seemed by the manual to be simpler (no redoing valve timing etc) to pull the powerhead. The vertical shaft WILL NOT release from the powerhead.
However I may have committed myself to pulling the power head. I have already separated slightly the powerhead from the oilpan(it wont move more than 1/4") so if I just tighten it back up I am sure it will leak oil....
I should have gone with my gut feeling
DOH!!
 
Ugg! It sounds like the vertical shaft is corroded or rusted into the bottom of the crankshaft. You may be able to rock the powerhead enough to break it loose. You may have to drain the oil (if you have not already) and turn the engine upside down and spray some pb blaster so it flows down the vertical shaft and hopefully it goes into the crankshaft end. You may have to spray several times and let it sit for a while. Then try rocking the powerhead again. If you are going to do any prying, make sure that there is something soft between your prying tool and the surface of the powerhead and lower surface.

You have probably already tried this, but at least you have someone with whom to commiserate.

Maybe Jimmy has some ideas on this one.

Mike
 
Yes! I do! But, as usual, you don't really need me because you have Mike! He pretty much said everything I would suggest to get the shaft free. The only other things I could offer are:

A product called AERO-KROIL instead of PB-Blaster. It works a bit better at "creeping" into interference fit joints like this and will definitely free it up IF GIVEN ENOUGH TIME TO WORK.

After the Blaster or Kroil soak, you could rig up a slide hammer affair to give it some gentle "bumps" in the right direction.

PATIENCE is the key here to keep from causing yourself more problems.

Good luck and now you have two people that "feel your pain" looking on and cheering for you.
 
So I followed your suggestions and sprayed a generous amount of PB Blaster down the hollow of the shaft, gave it a day.Some gentle "bumping" today worked it back and forth till.... SUCCESS!!! It came off. One note tho.... all that PB blaster I sprayed? Never did anything, The end of the shaft below the powerhead is solid:p
HOWEVER,,,, once I flipped the powerhead over to change the exhaust pipe revealed the pipe was in good condition. My exh leak was actually coming from between the pipe and the head. Directly opposite the water outlet the shoulder is melted/broken away:mad:. About a 1/4" hole plus some of the shoulder is a little thinner. NOT what I was expecting. I am assuming/hoping that I can clean it, rough it up, and build it up with plastic steel or some other product?? I don't use this motor enough to warrant a new cylinder head. Its only used for maybe 3-4 hrs a year.
 
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