I have a Cat D6C10K which takes a long time for it to run at full RPM. Hard to explain, but if you start it, it starts very easily, it seems to be laboring if you will, and blows allot of a black smoke. Power is inadequate for much more than just moving it around. As it warms up, the power get’s better and less black smoke. If I move it around and work it very lightly, and stop every five minutes or so and let it idle for a couple minutes, the RPM’s and Power will continue to go up. If I continue this process for an hour or so, it will eventually clear up and run like it suppose to, full power, clean exhaust. My fuel pressure is a little below the normal line, but it doesn’t change much from startup to running right, it goes up some. Any Ideas or suggestions?
try changing fuel filter. Sounds like it is plugged.
I've changed fule filters, I've pulled all the lines and blown them out, in addition to draining the tank, pulling the pump apart and cleaning it. I guess I do it all again.
How old is the fuel? Is the air cleaner clean, not just the element but the venturie (sp) section of the canister. I've seen bird nests cause trouble in there
The fuel in it at the moment isn't new by any means, it's been setting for several months, I'm guessing to say that the fuel in it now is about a year old. But it was doing that before it set, also after I put new fuel in it before. Which I'm sure some new fuel now wouldn’t hurt, but it was doing this when I ran for several days in a row with new fuel, and after it cooled off over night, same thing the next day. The air filters are clean, the air filter itself isn't new, but it's not excessive dirty I checked it last night. I started it without the filter just to make sure that wasn't an issue, and put it back on while it was running, there was no noticeable difference with or without the air filter. I've asked a local guy that's most likely forgotten more about dozers than I'll ever know, and he said it was most likely fuel related, as I don't work this dozer much, and he suggested that I get some fuel additive and run a couple tanks through it. After which time he seemed to think that it would clean up. I've put Lucas in the fuel and I've ran 30% of a full tank out, and it seemed to be better yesterday, (not taking as long to get full RPM's) and run like it's suppose to. I'll put some more in the remaining fuel, and run a couple tanks out as suggested, maybe that’s it. The fuel pressure gauge when running correctly is right on the normal line, never above the normal line, and a bit lower when I first start it. But as it warms up, the fuel pressure goes up, which leads me to believe that it's a fuel pump problem. It has the geared fuel pump, and maybe as it warms up its pumping a bit more and that's the problem. But I hate to change out the pump in a hope of it being that. Granted if it was 20 bucks, I'd be worth it, but the new pump is much more expensive.
Possibly a governer issue. Is that a naturally asperated 3306? ( no turbo)
I really don't know. how would I tell? If I remember correctly it seems like this all started at once.
My first guess was the fuel to air ratio. It's mounted on the governor and has a line to the intake, increases fuel as boost increases. The D6C 10K is turbocharged. However if it was the fuel to air ratio it would be low on power and to accelerate, but would not blow black smoke. My second guess is the turbocharger is not spinning up. I have had this happen to my D343 motor on the 637C. After sitting for months the motor started right up. It had no power on acceleration, wouldn't hardly rev up with no load, and blew the blackest exhaust while trying to run. There was a bit of carbon that had fell down into the exhaust side sticking the turbo from spinning. Was able to break it loose by going in through the clean air side and working it gently back and forth. Do you notice a difference in the sound when it's running ok? ie do you hear the turbo whistle? Do you hear that when it's running badly?
Doesn't sound like a fuel starvation problem if you're getting smoke...unless you've got more than one problem. I had two problems with my 10k that casued low power...turbo was shot and the governor was all corroded inside where the throttle shaft goes in. I ended up replacing the throttle shaft, spring, adjusting screw, and a few other small parts. I also went throuh the pump, but that was mainly to seal up leaks. Replaced turbo with remanufactured one and adjusted the governor to get boost up to spec. If the turbo is bad it could be sucking oil causing smoke....and if governor is out of adj, corroded, or has broken spring you'll have low power. You can attach a gage to the intake manifold and see what boost you're getting under full load....don't have the specs. but if I remember right it should be something like 5-6 lb. of boost....dealer should be able to tell you the spec. for sure. Not getting a lot of blow-by out of the crankcase vent tube are you?
I don't really hear much of any difference after just starting up or when it's running ok. I replaced my muffler which was bad and I don't see much of any black smoke at any point now, a little when it first starts. It seems like the throttle handle is really stiff when I first start it as well, but get's easier as it warms up. Maybe I just need to take everything apart and clean it all good and put it back together.
If it's power shift make sure the decelarater linkage isn't stiff, had it happen on my 8's from sitting and have to hook my toe under the pedal to get it up to speed. lube all the pivot points so it works freely. At first you were talking about black smoke and now you say there isn't any so I'm confused, a new muffler isn't going to cure anything :beatsme
From my experience, the black smoke and loss of power has always been a turbo issue... The fact that it eventually comes up to full power is a bit of a mystery. I know that my D6D takes a little a few minutes before it really starts moving and pushing with ease, but it doesn't have a black smoke issue. Good luck!!! www.petersfamilytrucking.com
I agree with all the above post ,but here are a couple other things that might cause your problems. A buddy of mine on his D6C had the scavenger pump for his torqe converter going bad.When it was cold the machine would hardly pull itself until the oil in the transmission got warmed up.The torqe convert had to much oil. It acted like you described. As far as the throttle handle ,being hard.Down under ther floor boards there is a detent that holds the throttle open so you can use the decelrator.It has a couple of small rollers and springs.They get rusted and either stick or won't hold the foot pedal for the decelrator clear open and it crips off and you loss rpms. I would have to keep pulling down on the handle throttle to get the rpm back up.The rollers and springs are not that high priced,and you might be able to just clean the ones you have.But for the price i would just replace them. Hope this helps.Good luck.:usa
If it is a slip-o-matic, oh pardon me (power shift) your tranny oil may still be thick so it is takeing more power to get it through the torque converter until it warms up. Just my $.02. Check your tranny filter make sure it is not clogged up.
My throttle handle got difficult to pull and it turned out the spring was rusted inside the governor (not sure if that's what it's called). We ended up taking it apart, from where the throttle linkage goes into the governor and rebuilding all those little pieces and installing a new spring. I guess it's a pretty common occurrence. The parts were $237 and the labor turned out to be $980. Since mine is a D6D with a 3306 and your C model has the same engine... Maybe it's a fix that will work! Good luck! www.petersfamilytrucking.com
Black smoke = not enough air. Exhaust temps climb and there is a chance you could melt something that shouldnt be melted. This is one of the cheapest and easiest ways of eliminating a turbo/exhaust problem. If possible, remove the exhaust at the turbo and try running it for a little bit. You will be able to see and hear if the turbo is spooling up. If the turbo doesnt seem to be spinning as fast as it should, you could have some carbon holding it back in which case you might be able to clean that up yourself or a bad turbo. If the smoke clears up and you gain lotsa power with the exhaust removed, then you have a restriction somewhere in your exhaust system.