what caused my engine to lock up?

[KYHunter]

I should have added this to my other post,sorry. My question is when I got the motor apart on one piston the rings were broken and the ring grooves distroyed. There was a little scoring on the piston as well as the cylinder. The crankshaft was broken and the lower main bearing was in pieces the ball bearings were flat on one side and the inner race was badly damaged. Please if anyone has a idea of what may have caused this to happen let me know so I can correct the problem I can't afford to rebuild it again.The water pump seemed to be working fine shooting a good stream. <br /> Thanks,KYHunter

 

[CATransplant]

Re: what caused my engine to lock up?

Yikes! It sounds to me very much like that cylinder was starved for fuel, and thus, lubrication. If this happened at WOT, that cylinder would have eventually siezed. Incredible stress on the con rod and bearings, plus the broken rings could have gotten into the crankcase and jammed things, causing breakage. There's a chance that this could also have been caused by a defective bore job that neglected to chamfer ports properly, causing broken rings.<br /><br />Sad business. What to do? Boy, I don't know. You're talking about another rebuild, with a new crankshaft, to boot. If you do, make certain that the rebore, if needed, is done by a place that handles outboards. If not, make sure the ports on the cylinders are properly chamfered.<br /><br />I'm sorry you are in this position and wish you the best of luck.<br /><br />You might want to consider a rebuilt powerhead, just to avoid the problem altogether. In any case, do make sure that all the carbs are functioning properly.

 

[pwiseman]

Re: what caused my engine to lock up?

I am not the expert, but the flat bearings sounds like your major failure point.

 

[Booner]

Re: what caused my engine to lock up?

KYHunter you may want to post the year, make, HP, becouse this new post and will help others to help you. i.e if it a Johnson post it there. Good luck.

 

[KYHunter]

Re: what caused my engine to lock up?

Sorry, Its a 1978 Johnson 115ETL78C.

 

[pwiseman]

Re: what caused my engine to lock up?

Originally posted by CATransplant:<br /> Yikes! It sounds to me very much like that cylinder was starved for fuel, and thus, lubrication. If this happened at WOT, that cylinder would have eventually siezed. Incredible stress on the con rod and bearings, plus the broken rings could have gotten into the crankcase and jammed things, causing breakage. There's a chance that this could also have been caused by a defective bore job that neglected to chamfer ports properly, causing broken rings.<br /><br /><br />Sad business. What to do? Boy, I don't know. You're talking about another rebuild, with a new crankshaft, to boot. If you do, make certain that the rebore, if needed, is done by a place that handles outboards. If not, make sure the ports on the cylinders are properly chamfered.<br /><br />I'm sorry you are in this position and wish you the best of luck.<br /><br />You might want to consider a rebuilt powerhead, just to avoid the problem altogether. In any case, do make sure that all the carbs are functioning properly.

How long would it take to flatten the bearings out? If the piston went first, would there be enough time to flatten out the bearings before the thing quit running?

 

[rodbolt]

Re: what caused my engine to lock up?

most likly the lower ball bearing failed first and fed metal to the cyl's. inspect closely for any signs of water damage to the crank. thats usually what causes that bearing to fail. any water coming from anywhere will tend to settle on the bottom bearing and cause it to rust. not long after that the bearings balls become sliders. sliders dont last long at all.

 

[wilde1j]

Re: what caused my engine to lock up?

I second rodbolt's opinion. I had a 1973 135HP which had water get in the lower main bearing, and it just locked up wrecking the crankshaft, etc. The block was rebuildable, but if I wasn't getting the parts at cost, I would have chucked it. That was a LONG time ago and as I recall, the crank had a list price over $650.

 

[jleus]

Re: what caused my engine to lock up?

Rebuilt a twin for a guy after he ran water contaminated fuel. Said the motor stopped running like fuel starvation. Lower main rusted. Best thing that happened was it set long eneough before he tried it again for the bearing to seize rather than run on rust. A clue on that one was the fuel pump. The metal parts don't like water.