Mercury Drive shaft is stuck in the motor head!!!

[Sonoma_Dog]

I am stuck! I just bought a 1985 35hp mercury outboard, Serial number: 6629125. I tried to replace the water pump and am not able to drop the lower unit. I have removed all five nuts as shown in the pictures!

After all the research on the internet, I am suspecting the drive shaft is stuck at the motor head. So I have mounted the outboard upside down, drilled a 1’1/2 inch hold and spray a LOT of liquid wrench penetrating oil in where I think the drive shaft is stuck (See pic) . After 4 days of penetrating oil / hitting it with hammer/ shaking it and the drive shaft still seems like it’s stuck there.

My first question is…. Is it really the drive shaft that causing problem? And if it is…..

WHAT SHOULD I DO NEXT?

1) Continual applying more oil / shaking it more

OR

2) Apply heat with a torch on the drive shaft. I am afraid that the shaft gets so hot cauing the plastic housing on the lower unit melt.

OR

3) Cut the drive shaft……and what to do afterward… how to remove the shaft from the motor head? And Can I weld it back together.

OR

4) Just grab a beer and say **** it…………….

Any advice will help! I really want to get this outboard working!

Thanks in advance!!!!

[Sonoma_Dog]

More pic

[freeportd]

I know your pain. I finally (after several weeks) managed to free the lower unit on my 1987 45HP classic fifty outboard. It had sat in storage for 7 years - and it was really stuck into the head. I followed all the hints, including running the engine while the lower unit hung on just the shaft - no go.

But, I did wedge chisels and pieces of wood (to keep the lower until parallel). I used ever increasing size of chisels - until I had it open about 3/4". I think hit upwards on the chisel (the engine was upside down like yours) - and that was with a 5 pound sledge. Many sessions of that, lots of penetrating oil, no heat - didn't have a hole cut like yours - and it finally gave when I really starting hitting on the chisel. It finally relinquished its hold! Make sure you don't miss the chisel and hit the cast aluminum.

Best of luck.