Stuck Powerhead

[Dana A]

Pulled many ! replacing the shift shaft I presume?
Don't know if you've already done this but

If your good with drilling and filling
Drill in from the side about a half to three quarters of an inch down from the powerhead thru each broken/seized head bolt
hook your lift to the motor ( I use a fork truck with engine on the boat)
Lift to put good tension on it then tap the back of the lower unit with at 4x6 block and a few whacks and they pop. I haven't had one not release. Now you have a 3/8 -1/2 in of the bolt to grab onto and will come right out with visegrips.

Now the the headbolts frozen into the mid section -
Same strategy drill one hole about the center of the headbolt in the mid section. Hit with blaster or whatever you use, then you tap / HAMMER top and bottom of the of the head bolt for movement. One end might be free. Frozen pieces I then drill at 1 inch intervals and some times your drilling them out from the top and bottom.

Filling the Swiss Cheese mid section
couple cans of parts cleaner and wash holes good
Fill all the the holes with JB Weld Steel Stik then re drill the holes when cured

Yamaha put these motors together dry, no lube/anti seize on bolts

Did these 1990's 150's on my grady one in 2014 the other in 2018
These older carb'd Yami's are bulletproof. "A carb'd yami wont leave you stranded"
grady motors.jpg

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