1994 Force 70 - powerhead removal

[cuda67bnl]

I know I should buy a manual for this thing, but I'd like to snatch the powerhead off right now, and not have to wait for a manual to get here. Not to mention I'm not sure at this point that I even want to invest much more in this motor. I've had prop shaft issues which I'll start a new thread about, but right now I have different issue. The motor has been running rough the last couple of times out. Hard to start, and idling rough, etc. Felt like it was running on 2 cylinders at low rpms. Brought it home a couple of days ago, and ran a compression check. Number 2 cylinder dead (30psi)...... Pulled the head yesterday and found that the number 2 piston is messed up at the exhaust port. Looks like maybe something went through the carb?? Can anyone tell me exactly which bolts need to be removed to take the powerhead off so I can split this thing and get the piston/rod out and see if there's any other damage? At this point I believe I may be able to just hone the cylinder and slap a new piston and rings in it.

 

[cuda67bnl]

Re: 1994 Force 70 - powerhead removal

Powerhead is off.....
Now to see about getting it split....

 

[Jiggz]

Re: 1994 Force 70 - powerhead removal

The pics shows a typical ring getting caught in one of the exhaust ports. I've had the same problem before. Not very familiar with the 94-70HP but if things are almost the same with the 89-125HP I have, you can replace the piston and rings without removing the powerhead. You can just access it from the intake side where the carbs and reed blocks are located. Search this forum for piston replacement and you will be surprised how easy it is do this.

 

[cuda67bnl]

Re: 1994 Force 70 - powerhead removal

I've got the motor split and the piston out. Definitely ate a ring.... I had wondered if I could just go through the intake side. When I took the rod cap off, the bearings went everywhere, so I'm thinking it was just as well that I had it all apart. Now to decide if I wanna fix it, or replace the whole thing. I'd really like to put a bigger motor on it.

 

[Jiggz]

Re: 1994 Force 70 - powerhead removal

The roller cage for the rod caps are split designed and normally will fall apart when unbolted. Replacing the piston using Wiseco piston kits would set you back around $200 including the gaskets if accessed from the intake side. If you want a bigger motor make sure the transom is rated to handle it.

 

[cuda67bnl]

Re: 1994 Force 70 - powerhead removal

The plate on my toon says it's rated for up to a 125, so I could go bigger if I found a motor.
I need to decide what I wanna do. When pulling the flywheel, the bolts pulled out of the threads, so I had to knock it off with a hammer. That broke the magnets loose on the inside. So unless I can glue them back on, I may need to also source a flywheel. I also need to try and hone the cylinder a bit before I make a decision, and see if it'll clean up some. There is definitely a small groove in it from the ring breaking. Looks like I can get a piston, rings, and wrist pin bearings for about $100 off ebay. I don't see any reason I can't reuse most of my gaskets.

Hate it when the motor looks like this........

 

[ferdly1]

Re: 1994 Force 70 - powerhead removal

Never ever reuse gaskets on a rebuild.

 

[cuda67bnl]

Re: 1994 Force 70 - powerhead removal

None of my gaskets are damaged. There's no reason to buy new ones. The case halves are siliconed, the intake gasket is fine, and I've read a hundred posts on here where the 'pros' recommend reusing the head gasket. So I think I'll save that money and put it towards the piston if I decide to rebuild.