Could be a low grade stainless??? Still looks like someones version of a heat shield.
Here's some info from back in the day....
 
 
 

Had a few questions regarding main bearing sets. The parts manual in the section showing the engine block group (4F7054) for my serial number shows part numbers for different shims that go with the main bearing caps. When we pulled the caps, there are no shims anywhere, and the bearing shells are aluminum . I noticed that at a later serial number break, the drawing showing the crankshaft and bearings changes over to different part numbers for the bearings. And there is a different engine block group shown (1H5655) that doesn’t show any shims with the main bearing caps. The crankshaft for all serial breaks shown in this manual all have the same part number. I’m kind of confused as to which main bearing set I should be looking for since there were no shims found. Crank seems to mic out to be able to stay using standard bearings. Need to ever so slightly polish a few journals, but there are no deep gouges that would necessitate machine work.

For 8U1-5951 use rod bearings 9F8580 and main set 4F6948.

The inside of the block got cleaned up a little better today and we found something in the number 3 hole that put the brakes on moving forward….

   

The best diesel engine machine shop in the area is going to come out when they can to take a look and see if they can machine that out in place and put a sleeve, or if they would rather we pull the engine and bring it to their shop for them to do it there. If the block needs to come out, then we’ll have them grind the crank the right way, which won’t be such a bad thing I suppose….

might be possible to lock stitch that crack. looks like it was a mould join

at least you know the inside and out now, if you remove it you will be sure another 50 years will pass

i would grind the rest of that mould line down flush. prevent further stresses.

I suppose it’s time for a bit of an update. Got the block back from Righetti’s in Stockton late last week. They are a Cummins engine dealer with a full on industrial engine machine shop. The founder, Ray Sr. (93 years of age with a tiger’s grip of a handshake) is actually who performed the repair. 

 

Ray pinned the crack, then he bored most of the way down, but left a little shelf at the bottom to land the 50 thousandths thick sleeve that he made and pressed in to complete the repair. 

Yesterday we attempted to put the liners in, but ran into a little bit of trouble with the stupid liner sealing bands that come in the CTP kit.  Ended up throwing the bands away as they are impossible to use, and we also ditched the crappy liner shims that come with the CTP liner kits. They are die-cut and their die set is either misadjusted or dull and instead of a clean cut with an even thickness of shim, their cutter distorted the stainless and left a sharp burr on one outside edge of each shim that adds to the thickness of the shims. We tossed them and ordered a full set from Cat (there goes another $17/hole). But what a difference in quality. They are precision ground to the exact thickness, dropped right into place without hanging up like the CTP ones did, and all liner protrusion measurements were right at 5 thousandths which is the upper limit of spec. 
We used a few bolts with some oversize washers to hold the liners in place and flipped the block over and got the cam and crankshaft (both polished by Righetti’s) re-installed with all new bearings. Checked clearances on the crankshaft with blue plastigauge. They’re all towards the upper limit of specs but they’re within spec, so that’s the main thing. 



Tomorrow amongst other things, the flywheel housing is going back on. I scoured the parts manual and I don’t see a gasket anywhere that goes between the block and the flywheel housing. I also couldn’t find a part number for a gasket that goes between the face where the engine oil pan butts up and bolts to the flywheel housing either. I may put some permatex on those surfaces where they mate together if nothing else to prevent any moisture from getting trapped in there and rusting them up. 

Maybe I’ll be a little better with taking more pics tomorrow…..its been a crazy few weeks running around chasing things down for this engine in addition to several other concurrent orders of business.


-Nick

My brother had Righetti’s regrind the crank on his D69U and used a CTP engine kit that he got from Tom over at associated. Interesting enough he was using it to pull a 15’ L disc and ring roller in his walnuts for some reason on what was permanent sod. Anyways the operator said it started knocking I believe and shut it down before anything came flying apart or welded together that should be if I remember correctly.

I don’t know if it had those bands of not as he ended up getting Mark Whatley over at Holt to come out put it together for him. It has held up for the past 10 years, although the tractor hasn’t been used more than a few minutes in the past 5 years LOL

Wow! Glad to see you back posting CR! Long time no see!
Nick: It will be a major loss if any of us lose a trusted machinist or mechanic. So fortunate here, as well as yourself.
After seeing some YouTube videos, it makes me wonder if CTP gets parts from Pakistan or India; It is very scary to see what they have to work with and the results.
Next rebuild kit here, I will have to ask my guy what he used.
I hope to see digging videos soon. JM