Day 10 - Crankshaft Examination

So now the crankcase is split, the next task is to remove the caps for the piston connecting rods, and remove the crankshaft and examine the bearings. Now one interesting thing I noticed on number 3 piston was that I was able to move the piston up and down like it was loose on the crankshaft - that indicated to me the bearing holding it firmly in place must have been destroyed, and that gave me some hope as to where those mashed up clumps of metal came from.


So after removing the caps for the piston connecting rods, low and behold I find the culprit (below). As you can see number 3 Pistons bearing is completely destroyed and only a small portion of it remains. You can also see that the rod itself and that section of crankshaft is a slightly darker color then the other piston caps and rods.


So I remove the crankshaft and place it on a towel along with the destroyed bearing. Whilst it's obvious this will have to be replaced, I will have to research if a new bearing is as simple as a swap with a new one as there must be a reason why that bearing had gone and not the others, but I also noticed on the piston rod for that piston there is no oil channel hole like the other piston rods have so maybe this has something to do with it - maybe that bearing was not getting any lubrication.

 
And below we have the crankshaft removed with the destroyed crank pin bearing sitting below the crank pin that it came from.