dt466e starting problems and smoke

[pratokko]

Sometimes the bus takes a very long time to start. Between attempts there is smoke filling the tail pipe even with the engine off. When it starts, it puts out alot of smoke for about 15 seconds.

It does not always do that. Sometimes it starts quick and smokeless.

Thank you

[magnakansas]

When you "crank" the engine the injectors are putting fuel into the engine but the fuel does not ignite and burn. The unburned fuel is the smoke you get after the engine starts. When the engine starts quickly, you do not have the build up of unburned fuel so you do not have the smoke. If the air/fuel mix can not get hot enough the fuel will not burn. some of the causes of not enough heat, are a slow turning engine, that could be a result of weak batteries not providing enough power to the starter motor. Bad connections at battery cables, Worn out starter motor. another cause could be worn pistons/rings/cylinder bores, that leads to low compression, low compression will not heat air/fuel mix enough to burn. anyways, lots of possibilities.

william

[pratokko]

Originally Posted by magnakansas

When you "crank" the engine the injectors are putting fuel into the engine but the fuel does not ignite and burn. The unburned fuel is the smoke you get after the engine starts. When the engine starts quickly, you do not have the build up of unburned fuel so you do not have the smoke. If the air/fuel mix can not get hot enough the fuel will not burn. some of the causes of not enough heat, are a slow turning engine, that could be a result of weak batteries not providing enough power to the starter motor. Bad connections at battery cables, Worn out starter motor. another cause could be worn pistons/rings/cylinder bores, that leads to low compression, low compression will not heat air/fuel mix enough to burn. anyways, lots of possibilities.

william

Thanks for the smoke explanation. The other things you mentioned cannot be the case since the engine sometimes starts right away. And also it cranks fast so no battery issue and once again, it could not be since it sometimes starts normally. thanks

[Brad_SwiftFur]

Does it start quickly after short amounts of time of being off, and harder to start after being off for longer times? Perhaps the fuel pressure is bleeding off and the fuel system has to build up pressure/prime itself after an extended shutdown.

[pratokko]

Originally Posted by Brad_SwiftFur

Does it start quickly after short amounts of time of being off, and harder to start after being off for longer times? Perhaps the fuel pressure is bleeding off and the fuel system has to build up pressure/prime itself after an extended shutdown.

I am not sure. I have to pay attention. But if that was the case how come there is smoke in the tail pipe. Wouldn't that mean the fuel system works? Thanks