removing powerhead

[JWGuns]

hey fellas - so im going to pull the powerhead on my 1990 40hp J40telesr and rebuild. I do have OMC manual and am more than capable of completing the project. so my first problem is the 8 bolts going from the bottom of the powerhead holding it on to the exhaust housing/mount are rusted over and rounded into what i would stretch to call "nubs" impossible to get ahold of with a wrench. Im thinking I'll have to carefully grid them off and then just replace the studs and nuts. Im just looking for some validation with the thought process before i proceed. any suggestions or previous lessons learned would be appreciated as im sure theres going to be quite a bit of cursing involved here. Thanks ahead of time!

 

[Dmopar74]

Easy out bits?

 

[F_R]

Are they 1/2" hex nuts? If they are, try a 12MM 6-point socket. Saved the day a lot of times for me.

 

[Bosunsmate]

Sounds like a salty. Some powerheads ive done getting these bolts off are90% of time spent.
The whole mid section length of the bolts are often seized to the holes they are in.
Ive had to drill near the top of the housing sometimes straight in and throught the bolt. Once they are all drilled through then put some heat into that hole to loosen the oxidation between there and the baseplate where the powerhead sits and then lift, pry it off.
Just fill the holes later with epoxy and remove the rest of the bolts from the top down.
The bit of the bolts left in the bottom of the powerhead actually 99% of the time unthread easily, its the midsection length where the aluminium oxidises to the bolts is the main problem in my experience.
The two studs ive never really had a problem with apart from those in the exhaust housing, which i reluctantly drilled out once and replaced with a bolt

 

[boobie]

Driving a smaller metric socket on them may work along with some heat. Check with Harbor Freight as they may have something for this. Don't use EZ Outs because if you break one off you're screwed.

 

[JWGuns]

Thanks for the suggestions guys I'll give it a go later tonight and let you know how it goes