Hi Everyone. Please i need some assistance to the diagnosis of a D8R Bulldozer which i just changed the top cylinder because the initial one had a crack. After changing it, it worked for about 8 hours and loss power and black smoke coming from the Exhaust manifold. I removed the top cylinder again to regrind the valves. I also tested the injector nozzles and they are okay. The black smoke is still there and there is no power to work. At low idle the smoke is okay but when set to work the black smoke is terrible.
Turbo failure
i have rekitted the turbocharger at a shop and it is the same. Is it possible the elements of the Injector pump is defective?
Has it got a positive air shutoff that is partially closed or is the after cooler blocked.
i flushed the aftercooler with steam pressure washer
Dear Mobiltech, i have changed the turbocharger and the power of the equipment is restored back. But i noticed the turbo blow some kind of whistle when the engine is revved. Also, when some black smoke when i tried to push a heavy load but it pushed it with ease. Are these things normal? Another observation, at the highest idle it seems to miss fire after about 20 seconds. Hope to hear from you soonest as there is mighty job for the D8R to work in a thick forest full of trees.
An 8R black-smoking under heavy load is not normal, they normally burn pretty clean. It would seem to be either getting too much fuel or too little air. Was the replacement turbo that you installed a new one..? Also was it a genuine Cat turbocharger..? What is the condition of the air filters..? As an experiment just for a couple of minutes try pushing a heavy load with only the secondary (small) air filter in place and see what the smoke looks like.
Dear Mobiltech, i have changed the turbocharger and the power of the equipment is restored back. But i noticed the turbo blow some kind of whistle when the engine is revved. Also, when some black smoke when i tried to push a heavy load but it pushed it with ease. Are these things normal? Another observation, at the highest idle it seems to miss fire after about 20 seconds. Hope to hear from you soonest as there is mighty job for the D8R to work in a thick forest full of trees.
Dear Nige, thank you for your response. The replaced turbo is a genuine cat but not a new one, it was removed from another working D8r bulldozer. I removed both filters entirely to carry out the test. Also, the top cylinder was just replaced about 6 weeks ago and all these troubles started coming up. Have had the valves ground once and reground a second time when it seemed it was misfiring at high idle
Dear Nige, thank you for your response. The replaced turbo is a genuine cat but not a new one, it was removed from another working D8r bulldozer. I removed both filters entirely to carry out the test. Also, the top cylinder was just replaced about 6 weeks ago and all these troubles started coming up. Have had the valves ground once and reground a second time when it seemed it was misfiring at high idle
i finally replaced the Injector Nozzles and the black smoke has stopped. Also the machine has an improved power. But along the line, i can hear a loud clicking sound like that of valve and coming from the exhaust manifold. Is it possible the valves needs to be reset?
I would do a valve set before doing anything else. Even if the valves are found to be correct at least it eliminates them as a potential problem. If you had the valves ground (twice) before installing the head then the chances are good they will need adjusting again.
okay. Thank you very much.I will do that immediately and give a feed back.
Could the clicking be from a leaking exhaust manifold gasket? A valve set would be a good idea. Sometimes the clearance can change after running and seating everything.
please is it possible for a faulty cylinder head to cause a 3406 engine's Injector Nozzles not to combust and be wet with diesel resulting in black smoke and a reduced power from the machine and the engine does not overheat?
I would not have thought it was possible. The "wet with diesel" comment indicates to me that the problem is with the injectors themselves.
Is it possible to get a gauge and check the boost pressure both before and after the aftercooler? You may have a blockage on the air side. I'm not suggesting that your machine has been poorly maintained, but I have seen machines which have been run with leaking exhaust systems draw soot into the intake and block the aftercooler. (For anyone reading who is not familiar with these engines, they have an air-to-water type aftercooler)
When you installed the injectors did you use the proper sealing washer to get the injector in to the right depth?if the injectors are not in far enough or too far it could cause a spray pattern problem.
Thanks guys, i greatly appreciate the efforts. It happened that my injector pump was defective. Even after changing the plungers it did not improve much until the whole unit was replaced. This equipment has not,been used for over two years. Before it was parked, i worked on the transmission then when the forum assisted me severally. The equipment while working at a site recently, on the 18th november 2015 suddenly had a reduced performance at some point in time it doesn't move in The first speed front and back when hot. But when cold it moves but still have a reduced power, i check and saw the pressure for the first speed is 0kpa and that of second and third are about 450kpa. Even the pressure from the transmission pump on a day when it stopped gave me 0, but i have not tested while cold. I checked the transmission filter behind and saw nylon particles like those from a seal, is it possible a seal inside the transmission is making it loose pressure?