Possible 6V92TA Injector Troubles...

[Highway Yacht]

Ok guys.. Got a Detroit problem question for you but first let me describe the symptoms. I have a 6V92TA DDEC engine. Engine starts fine with basically NO smoke at all. I can gradually increase throttle slowly up to as many RPM's as I want with still basically NO smoke. But...If I hit the throttle hard and bring the RPM's up fast I get a huge puff of a white/greyish smoke that is way more than usual and sometimes a slight stutter in the engine maybe like a single misfire. The smoke last for 15 to 20 seconds and then clears up even if I keep the engine rev'ed up. Basically it only does it on hard accererations and once the RPM's level out, the white/greyish smoke clears back to almost no smoke at all.
I was told that it is probably a bad single injector that is squirting fuel into the cylinder instead of misting the fuel as it should. I was told the squirted fuel from that injector was not burning as it should and was getting into the exhaust thus causing the huge puff of smoke on hard accelerations. I always thought diesel fuel burned black and not white or grey. I was told to disconnect the Y tube just before the turbo and see which side of the engine the smoke is coming from. Once I found out which side, then remove the manifold on that side to see which cylinder it was coming from and that would tell me which injector is causing the problem. Knowing my symptoms, does this sound right to you all. If all this does sound about right, can these injectors be cleaned or do they need to be rebuilt or replaced??? If my info doesn't sound right, could you lead me in the right direction?.. I do not have a current tag or insurance on the bus so taking it to a Detroit mechanic would be kind of difficult at the present time.

[JackConrad]

Not sure about your injector problem, but black smoke is incomplete (partial) combustion. White smoke is unburned (raw) fuel. Blue/gray smoke is oil burning.  Jack

[RTS/Daytona]

BECAUSE you have a DDEC - Just go to someone who has a PRO-LINK and have them do a "CYLINDER CUTOUT SEQUENCE" do one cylinder at a time - punch the throttle for each test - until you find the trouble - simple as that.

see SOME trhings are easier with a DDEC then and MUI

[luvrbus]

Don't even worry about it till you can take the bus on a long run it is just a cold cylinder and will come back to life after a good run.
That is about normal for DD to do that if it was a bad injector it would be black smoke after warm up. 


good luck

[Highway Yacht]

There is never any huge puffs of black smoke after it warms up. I know the last time I did have it on the highway which was a couple years ago, it smoked huge amounts of white smoke for the first couple miles just on the hard hard accelerations like taking off from a dead stop but after that I never noticed any smoke at all. I drove almost wide open on the interstate for 7 hours without a glitch or any smoke except the first couple miles. I've never noticed ANY blue smoke ever, nor have I really ever detected much of an odor from the white smoke to see if I could smell a burning smell of any kind that would lead me to the cause. But, after the 7 hour drive, I let it sit for a week or two other than moving it around in my driveway or it sitting still on fast idle while I was checking for leaks, noises, etc. After the week or two, I took it out for fuel and the huge puffs of white smoke were back again, but again only on hard accelerations until either the engine warmed up or either the unburned fuel was finally purged out. My only other concern was maybe water if there was a cracked head or head gasket but I'm praying that isn't the case. I have had to add small amounts of water to the radiator maybe 3 times in the last couple years but in all it might total a gallon at most. My main reason for concern is that I am getting ready to sink some pretty big money into the conversion this summer and would hate to do that and then find out I had a MAJOR costly engine problem. Like I said before, there isn't much of a way for me to take it to a detroit mechanic right now since there is no tag, inspection, or insurance on the bus at present. I also have the windows out and bay doors off in preperation for new side skins and hinges and it would never pass an inspection like that to even get my tag.

[Highway Yacht]

BECAUSE you have a DDEC - Just go to someone who has a PRO-LINK and have them do a "CYLINDER CUTOUT SEQUENCE" do one cylinder at a time - punch the throttle for each test - until you find the trouble - simple as that.

see SOME trhings are easier with a DDEC then and MUI

Is that Pro Link something that I would most likely only find at a Detroit shop or is it something that is fairly common with most diesel mechanics?? I would have to find someone that maybe works on Detroits on the side and would be willing to bring it to me since I live in a rural area and can't drive the bus 20 miles into town without tags and insurance, windows, etc.. Would it tell me what is wrong such as a cold cylinder, bag injector, cracked head or just point me to the cylinder and then have to figure it out?

[luvrbus]

J, a pro link will not tell you if the head is cracked,bad head gasket or a cold cylinder it cuts the injector out just like Pete says.
A bad injector will not change cold or hot
I would not worry about but that's me with the water lost is probably cold water leaks from the hose connections

good luck

[Chopper Scott]

It seems like everytime I am working on my bus and starting it off and on, and pulling it in and out of the shop that the first time I head out on the road it blows gray smoke for the first mile or so when I jump on it. Then it clears up. I think Cliff is right and you really need to blow the cobs out of it and run it hard before diving into it. All kinds of gremlins show up on a bus that is not beatin a path down the road. Go out and sack some Swift or Roadway trucks and both the bus and you will feel better!

[Highway Yacht]

Thanks Guys... I do hope that running it is all I need to do.. It does make me feel a little better about it..

[pvcces]

If you run the engine very much without going anywhere, you will get exhaust loading and your big cloud. Don't run the engine until you have someplace to go, and your problems will be minimized. Do not run the engine to charge batteries or warm the coach for the same reasons.

Good luck.

Tom Caffrey

[buswarrior]

As noted, forget about the engine until AFTER you go for a long drive.

Don't expect anything to work right if it isn't worked.

engines, brakes, legs, hips, shoulders, backs....

happy coaching!
buswarrior