TOPIC:

Question- On the lower crankcase half there's a web behind the 3rd and 4th main bearing. Is that a nick I see in the web that might have been made by the primary chain bumping up against it?

I see that too Kawboy. In one photo. That would perfectly be where it would happen, so I am also wondering. That's that same web we talked about earlier. I will be removing a couple of millimeters from there - just in case.

Attached the pics up close of two(!) areas where damage has occurred. I think from both primary and cam chain!

I have cleaned up the crankshaft bearings and they look OK, but will need to measure. There are no markings on the crankshaft whatsoever, so acc to the manual I need the largest inserts, blue. All the bearings have D90 stamped into them.

Cases now cleaned and empty, and will be sanded and painted tomorrow.

Meanwhile cleaning up the bolts.

I see clearly marks what I think are from cam chain. But not from what I think would be secondary chain - on that triangular web, what I expected to see.

All the bearings have D90 stamped into them.

What do you mean by the 'bearing'? Could you post a photo? I can't find anything on mine. Are they really stamped or is it already part of the casting?

Another eastern egg: the connecting rods big end bearing caps I have have these markings as seen on the photo below. They don't seem to be consistent to the direction of the offset of the rod - like the top two. One is to the left, other to the right. I just have these four which I purchased together, so I have no idea how were they positioned on a crankshaft.
Could you take a look at yours and tell me what they say, and what position and what sequence are they installed in? I couldn't find anything about it in the manual, perhaps missed it, and I'm trying to figure out a formula. Hard to do it without having all six and a reference point.
Oh, and all mine have S5 on their side, also cast along with the whole rod, not stamped.

12 2 cast in to the rod would usually relate to a foundry date. Down the road if there's a run of flaws and the foundry dates are the same, the failure can be attributed to a foundry practice or a bad metallurgical blend.

Number stamped indications are related to machining. If a +10 or -10 or a letter are stamped in the rod, it helps on line assembly fitting the various sizes of plain bearings.

Attached pics of the crankshaft. All of the rods are orientated the same way. Mine have the same numbers on the bottom, but additionally S1 on the side.







In addition here is a pic of the bushings/bearings, on the left as they came out of the engine, on the right after a light wipe and polish. Looking OK I think. New ones will be USD 35 times 18, so quite a lot of cash!



Finally here a pic of the stamps on the shells, most have D9D on them but a few (from the top crankcase) have D9C....?



I have just finished sanding the cases and hopefully tomorrow I will take them, together with the crankshaft, to someone who can ultrasonically clean them. Then paint-and-bake. I have also sanded the bolts' heads and painted them, to go into the oven tomorrow.

That's great progress Paul. Have you decided on the connecting rods - leave as is or dismantle?

Connecting rods: Could you tell me, or take a photo, of the bottoms of the connecting rods like in the photos I posted? Mine have " - 12 ·" and " 12 ·".
I see your sides show "S1·····" while mine show "S5"


Main journals: I think I had a moment of miscommunication speaking of conrods not main bearings. The con rods bushings have no markings, the main journal bushings have as well. Quite interesting to see yours are all D9D. Here what mine say: D0D, D0B and D0A.

I suppose those forged marks correspond to what Kawboy says - the batch, the place and time where they were made.
The stamps on the bushings I think would correspond to thickness, but I can't find any info about it except the colors, which no surprisingly are gone.

Any leads on deciphering these?