Hello, Sorry for popping up every 3 years only when I have a problems. My komatsu pc130-8 engine was recently sleeved and overhauled. After overhauling it oil comes out of the breather when the excavator is a work. What happened was, the c-clip for the piston pin [ sorry I'm not a mechanic so I don't know all the proper names] came out and caused the pin to dig into the bore, cylinder #2, and because if that I added just 1 sleeve to that bore. The crank shows changed as the bearings at the time got damaged and did some damage to the previous crankshaft. At first I thought it was just a simple oil leak but what but going further in to engine made us see what the real problem was. So the rear crankshaft seal blew out causing oil to run over to the damper case where initially I was seeing no leaks until I hears the bearings knocking, at that time it was too late the crankshaft got damaged. My mechanic put the engine back together with: New #2 piston and connecting rods Bearings - main, connecting rods, camshaft, [genuine] Kmp seal kit Piston rings [genuine] 1 Kmp sleeve kit for #2 cylinder Mounted the engine mid January and went to work, after a week I stopped. Too much oil leaking. Removed the engine again last week and noticed the second rings on all pistons were upside down. Couldn't identify any other thing that was out of the ordinary so we mounted back the engine. Gave it a hour test run, digging in the yard and there was oil again but not as much as before coming out of the engine breather. This only happens when the machine is work and engine is at maximum output. Note: before removing the engine there was none of this happening, even while the bore and bearings was damaged. When we first opened the engine there was rings seized shut onto the piston. The machine never felt like it was lacking power. When my machnic did some kinda engine pressure test he mentioned it being at 4psi [I'm not sure how this works] When i went onto the monitoring panel to check the tubro boost pressure it not hit a maximum 2.265 [im not sure of the unit of measure] Even now after the overhaul the machine doesn't feel like there is a massive drop in power, it does not smoke at all, it runs quiet, smoothly. But there the oil leak through the breather when the engine is a maximum output Someone mentioned to me that it could be the turbo which I find is strange. Can anyone help? Sorry again for not being more frequent here assisting other people.
I guess this is beating everyone
We didn't rebuild it, we can't be there to perform a detailed inspection or failure analysis and your photos don't inform us of if this is the original failure or the current one. Your description saying the piston rings were installed upside down is your problem. If all you did was turn to the right direction and reinstalled them, you made another mistake. The cylinders will have taken a glaze after the first rebuild and the rings would have seated to that. At the least you should have done an light hone to the cylinders to break the glaze and probably should have installed new rings. It appears that all your problems with the engine were caused by undertrained and inexperienced personnel.
Did you solve this? We have the same problem.