i have a early komatsu pc95 that i use around my house recently this thing once it reaches normal operating temperture starts boiling gray smoke and knocking then will not idle down or shut off with the key.... right before you think it is going to self destruct it will die.... i was told by a local mechanic that the air filter was stopped up so i replaced it done the same thing then another guy told me the oil seal in the turbo was pushing oil in the intake was my problem... machine does not have a turbo.... the machine runs great until temperture gets half way then its cut key off and run because you never no if it is going to cut off or blow up.... so i am lost with what could be wrong with this thing PLEASE HELP
i believe 1993 year model
Rings are more than likely shot, is the machine overfull on oil ? Pj
it is a little over full on oil.... doesnt smoke until this happens could rings cause that...
Are you sure you have the right dipstick? did it take the right amount of oil the last time you changed it? How much oil does it use? Any chance the oil is being diluted, raising the level and burning up? If it was me, I'd be draining the oil, even if it's into a clean bucket to pour right back in after checking. Sorry for so many questions, doesn't make sense to me. PJ and I both think the engine is sucking oil and running on that, but it's hard to believe it would start and run without smoking and then start leaking that much oil past the rings. Other WAG possibilities: oil leaking into the intake, valve stems? there aren't any other ways for oil to get into the intake are there? You don't have an oil bath air cleaner, do you? Bad injector? How long does it run after you shut off the key? Also, for an emergency shut off, you need to cut off the air supply to the engine, like a piece of thick rubber (sidewall or belting) you can place over an intake pipe, or a fire extinguisher to empty into it, but it doesn't sound quite that bad yet.
i am going to change oil today it needs to be changed any way...... but yes it is sucking oil and running on that..... it is almost like you flip a switch and cut the diesel off and turn the oil on.... up until that point it runs great no smoking no missing very good machine but in that instance it starts boiling smoke out missing knocking and the throttle is not adjustable it just revs up and eventually will die prob around 1-2 minutes but its long enough to make you panic.... no oil bath filter regular paper filter.... i bought this machine last year one track did not pull i fixed that and used machine alot from august-november and has been sitting since then tried to use it a couple weeks ago and this starting happening everytime the machine runs for about 15min it starts this problem has done it 4 times im starting to get scared to even crank it now would hate to have to buy a motor.... thanks for any and all input
After checking the oil quantity/quality, the obvious step is a compression test. Or if it's easier for you, take off the exhaust manifold and see if you can tell which cylinders are affected. Any idea on the hours on the engine? or the amount of oil consumption?
5000 hours I changed oil it was way over full had a lot of diesel in it what would cause this. I ran machine for about 30 minutes with no smoking no missing ran great. After shutting machine off rechecked oil and now is over full line seems to have diesel in it again I would think that if it was a internal engine problem it would smoke miss or knock wouldn't it?
Check the pipes between the air filter and engine
does it have a crankcase vent or pcv system that goes back into the intake? Sounds like the fuel vapor is your trouble any way first stop the fuel leak maybe that will fix it.
Diesel could leak into the oil in a few places: transfer pump, injection pump, injectors... I don't know this engine, those are guesses. But start at the transfer pump, it's easiest. And congratulations on saving yourself an engine rebuild, so far.