1976 9.8 110, running WOT, locked up and died

[benyshep]

I recently got a 1976 Mercury 9.8 that had not been used in the past few years. I changed the impeller and it ran okay with the exception of a metallic rattling sound somewhere on top. I was cruising along with it pumping water for 30 minutes on a lake and at WOT it stopped abruptly. I checked the rope and it was stuck. I removed the cover and the engine wasn't hot to the touch. I had proper fuel/oil with some carb cleaner added. The prop spins fine in neutral, but can't use it to turn over motor in gear. What should I look at first?

 

[mellowyellow]

Re: 1976 9.8 110, running WOT, locked up and died

I would inspect the lower unit first.<br />did you wrap anything around the prop?<br />once l/u is removed, try to turn flywheel <br />by hand. post back results.<br />good luck,<br />M.Y.

 

[benyshep]

Re: 1976 9.8 110, running WOT, locked up and died

Nothing was found wrapped on the prop when it died. I removed the lower unit and the plugs. Nothing appeared damaged except the lower plug was a little more black. The flywheel would not turn by hand. I was able to free it up by carefully prying on it a bit. It is now back together and turns over fine; I haven't started it yet. I don't know what could have caused this, but think I should look for loose stuff on the top that could have made it stop, any ideas?

 

[jasonballard]

Re: 1976 9.8 110, running WOT, locked up and died

I have had the same problem on my 1973 9.8 110. The sound is caused by what are called pawl washers. They hold the pull starter, but sometimes become loose and start hitting the flywheel. Read some of my older posts and a guy named Crom told me how to fix the problem. Nothing with the motor to worry about, cheap but very involved fix. Don't be drinkin' beers while doing it.

 

[benyshep]

Re: 1976 9.8 110, running WOT, locked up and died

I replaced all wave washers in the starting unit. I found that one was MIA. When I ran it again, I heard the same noise and it quit. I decided to remove some covers and look at the cylinders. The lower cylinder has scratches all over it and a metal check came out of it's exhaust port. Looks like a rebuild on the powerhead. Is it worth the investment or should I consider it a parts motor? Thanks for the previous posts.