Galling on 6.5 Cylinder Bore

[befland]

Tore down a 1993 6.5L engine that I had sitting in the garage. I don't have any history on this engine (miles, etc) so I wanted to tear it down to see if it was worth keeping.

The outside of the engine was filthy (front seal looked like it had been leaking a long time but no groove on the crank). The inside of the engine was really clean. Cylinder bores 1,2,7 & 8 were like new. Cylinder bores 3,4,5 & 6 were gallded right at the very top and the piston skirts were scuffed up. What would cause this? The rod asm was tight and the bearings seemed to be in good shape. Could this be caused by a lean condition or maybe started fluid?

[DmaxMaverick]

The cylinder/piston damage could be caused by any number of reasons. Extended overheating is at the top of the list. Poor quality air filtration (K&N and the like) isn't far behind.

A Diesel engine can't run "lean". The inlet isn't throttled, and all power/rpm control is via fuel volume and timing. Too advanced timing can cause similar issues, but excessive clatter is usually enough to get it corrected long before damage occurs.

[Robyn]

I agree with Maverick on this 100%

Take some good high res pics and post them here please.

Take the pics of the bores and the piston skirts.

Heat is a biggy

Missy

[argo]

Just Subscribing to this thread.

[befland]

I'll take some pics as soon as I get a chance. Block is at my uncles shop so I'll get over and get some. However....I'm pretty sure running hot is the culprit. Everyone that has seen it says the same thing. On the bright side though...it looks like a build-up of AL instead of a gouge. It looks like I could hone out the AL and not have to bore. Of course I'll have to check it after I get it cleaned up.

One question though. Why are bores 3,4,5 & 6 the only ones affected? I would have thought that 7&8 would have been the hottest running cylinders.

[Kennedy]

What percentage of the total cost of this build does boring represent?