1986 e140tlcd

[rtek816]

Hi All,

Rebuilt this motor last year and have 170 hrs on it. Last weekend, started it 5 miles offshore and heard a ticking noise. Ran in and it would'nt idle in the no wake zone. 45 lbs comp in #2. Stripped down and the ring on #2 was in 3 pieces. Small burr on the downstroke intake port. Any idea what happened? All pistons were .030 O/S and fresh bores.

Thanks,

Bob

 

[schematic]

Re: 1986 e140tlcd

I see little or no chamfer on those ports. I also see lots of scuffing and no cross-hatch left on that fresh bore.
1.Were you getting max rpm when you headed out?
2.Did you feel any degrading of power indicating fuel starvation?
3.Do your overheat alarm sensors work?
4.Any other cylinders scuffed?

 

[rtek816]

Re: 1986 e140tlcd

Schematic

I don't see any chamfer on any of the ports. The shop that bored the cylinders was reccomended by a large marina as they do all their boring. The engine has been running fine. No fuel starvation and there was oil in all cylinders when I tore it down. Horn works and O/H sensors work. The rest of the cylinders look fine. Can still see the crosshatch. How much of a chamfer should there be? On all the ports?

 

[schematic]

Re: 1986 e140tlcd

should be no sharp edges on any ports. small chamfer all around especially the edges parallel to the heads

Sorry, I don't see much for cross hatch. Only scoring....

Dhadley would know best....

 

[rtek816]

Re: 1986 e140tlcd

Update...received a new piston and took it back to the machine shop. Pretty much had to argue with the owner. He claims it got hot as there is scuffing on 3 sides. I told him if that's the case, why don't the others show any signs of oh. I said maybe the bore was too tight? He is going to clean it up and hopefully there's still enough material to get me back together. He swears there is sufficient chamfer on the ports. I'll know more on Monday when I go pick it up. 3 prime weekends lost to this screwup and hoping to be back on the water by the 4th. Question....how much clearance between the piston and cylinder is appropriate? 90 degrees from the wrist pin?

 

[schematic]

Re: 1986 e140tlcd

seeing it last 170 hours, I doubt it was clearance. It would have piled up sooner. I'd suspect overheating in that cylinder likely caused by fuel starvation. Better go through the carb maticulously.