My Cat 3306 engine with 250 HP. Engine arrangement 6N1309 I started it and black smoke came out of the exhaust, let it run for a while 5/10 minutes and still black smoke. The last time I used it was fine no black smoke. Maybe some one messed around with it in the field! Air cleaner is clean. What could be the problem? What could some one have messed with to cause the black smoke. Last time I changed oil I had an oil analysis done it was report iron was high. hours on engine 3998
My 977L with the same motor did the same thing, long story short, it was the turbo. There should be a 1/4" pipe plug on the intake side of the blower, hook a vacuum gauge to it and see what you get, no vacuum...no good. Nige, please add your input.
It has a new turbo on it this summer before I parked it until now, it worked fine when it was parked.
Does it have a boost compensator on the back of the pump.. air line going to it from the manifold?? Real easy to run the fuel up before the turbo spools up.. to much fuel before the air gets pushed in.. You should be able to see the paint off the bolts real easy.. Does the smoke clear up when its on the road..
Black smoke at idle ? Crack injection lines see if it goes away.
Not a bad idea to eliminate something causing too much fuel in one cylinder! Said "turbo was new this summer" well hate to be an *** but just because you put a new window in last week if some kid threw a rock at it this morning it could be broke. Pull the intake hose off and at least see if the wheels turn nice and free.
Good one Ken. And just because your furnace air filter is clean, doesn't mean the shtter's not plugged up! I wonder if water could have gotten in the air intake lines somehow and froze? or mice... Kind of out there, but black smoke at idle isn't just "too much fuel", more fuel means more power which makes more speed which makes the gov shut down the fuel. Unless there's something dragging on the engine causing it to lug at idle? One leaky injector would do it too, especially if the smoke is uneven color or the engine has an uneven knock. What's this in? and did you use it after it warmed up?
Well its been a while. I took the injectors out and had a shop look at them, most of them were bad. Acquired new ones and put them in. Have not yet started the machine but thats the problem, the injectors would not stop the fuel it would just keep flowing into the piston chambers.