Building an engine & a bike from random parts - 1979 - 1981

Getting close to the crucial pivoting point - sorting out the crankshaft and connecting rods.
The connecting rods - I only have 4 and still looking for 2. There are no markings on them, so I will have to check their weight and continue search - when available.

The crank case 1981. The crankshaft 1981.

The crank case has "0" marking and the crankshaft has 'No Mark'. (there is a mysterious 'AM 2' on the cast, I wonder if this indicates perhaps just where it was made, like I suspect similar markings on the water pump mechanical seal housing).
So, I am looking for 92028-1104 and 92028-1107 bushings (black). I am going to confirm this and readjust after taking measurements and eventually checking with plastigage.

I also chased all the main threads with a tap - I suggest doing it no matter how clean your engine is you think. Lots of dirt and some aluminum came out. Now, all are shiny like new and ready for screw

Spare block I was going to use but found a better solution with the one I purchased for CAD 20 if I remember it correctly. So, this one I am just messing around with. The good thing is it came with 6 good pistons, and all the water pump shafts and gears in perfect shape! Including the nylon one. Plus, the water outlet housings, all good. All 6 cylinders are great as well - just need deglazing. So I have a stash of good spare parts. Time to take it apart and a point I want to make is to show how things might be nasty underneath. Just look at all the crust left after whatever coolant was in there.

Despite all the mess, the shaft surfaces are surprisingly fine. The back of the mechanical seal is not.
I suggest to either check it and take a chance reinstalling, or getting an available set of new replacements. You know what I'd favor.

Despite overall good look when removed, that rubber inside the mechanical seal component is brittle and not usable.



From what I see, my wild guess is when these fail it's not due to the ceramic component, as the 'mechanical' word would suggest, but probably mostly the rubber innards becoming brittle and stopping to create a barrier. All the whitish ceramic, including the rubber sleeve in which they sit, are looking ok. But this inner rubber piece I could just crush into pieces if I wanted to.

Stan, following on from my thread, the numbers on the bottom of my conrods are same as yours. All of them are marked: -12 1.

As I got the primary chain off the crankshaft without removing the conrods, I will not dismantle mine, so no idea what bearing shells are in there. There is no movement so I think they are OK.

The only shells I do have out are the ones that go into the cases and support the crankshaft (= journals?). I cannot find any info on what the markings mean (mine D9D with a few D9C, and yours which are D0D, D0B and D0A) but suspect they are thickness.

Thank you Paul. I am trying to find info on those codes. I will report when I know something.