Mercury 650 65hp Drive shaft removal

[keenrefox]

I can not seem to get the bolt that holds the pinion gear to the lower drive shaft off any tricks to this im missing?

 

[keenrefox]

come on guys someones had to of done this before!?!?!

 

[Moody Blue]

I've removed a few of these on 1971 vintage 80hp units. NOT an easy task I have to say. I custom ground a box end wrench to get a good fit over the thin profile pinion nut. I then found a 12pt socket (can't recall the size) that fit over the splined end of the driveshaft and used an impact gun to spin the nut off the shaft.

 

[TMAD]

I am working though the same thing right now.
I have a 1968 650 SS and I think this is the first time this thing has been apart. Everything is very stuck and takes lots of mussel to get it apart.
If yours is the same as mine, then you should be able to remove everything from inside the lower unit once the prop shaft is out. If everything is out then you should be able to get any type of wrench or socket you want on it. I used a 7/8” socket with ½” drive ratchet and a short pipe on the ratchet to give me the extra torque. Put the drive shaft in a good vice and clamp it down tight. I had to change from my small vice to my large one because the shaft was still spinning inside the jaws of the vice. Once in the vice use slow pressure to turn off the nut.
I have gotten this far right now and as far as I can tell, I should be able to pull the drive shaft right out of the unit but no luck. I have been beating and beating on it but I can’t get it to budge. I would guess that the shat is corroded onto the lower bearings of gear.
I need to take mine apart because the shaft is pitted where the oil seal is in the water pump and i will need to re surface then sleeve the shaft before I can put it back together. That is if I can get it apart.
Good luck with yours.