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Big11beard 06-08-2015 07:07 AM

1997 Freightliner 3126 white smoke and power loss
I just purchased a 1997 school bus with a 3126. Under load when the turbo starts to spool it starts blowing white smoke and losses power. I thought clogged fuel filter but symptoms are the same after the change. I checked the turbo and the compressor is spotless inside and shaft play is less then 1/16" and spins freely. Any suggestions? I'm new to the diesel seen.

M1031A1 06-08-2015 07:42 AM

Blown head gasket. White is steam from the coolant getting into the combustion chamber. Just based upon what I'm reading.

cowlitzcoach 06-08-2015 08:14 AM

I would agree white equals coolant getting into the combustion chamber.

I would take it into a shop to have it professionally diagnosed before much longer.

If you do have a bad head gasket it could fail totally and hydro-lock your engine at speed. At that point you can break connecting rods, crankshafts, and other very expensive parts.

Good luck.

Big11beard 06-08-2015 08:51 AM

I checked the oil and it didn't look like water was making into the oil but I suppose water could be going only into the combustion chamber. How would I verify the head gasket and is it reasonable to replace it myself?

cowlitzcoach 06-08-2015 09:29 AM

If the only time you are getting white smoke is under acceleration it probably won't show up in the oil--it is getting consumed in the combustion process.

Which is also why you need to address the problem ASAP. If the only time it leaks is during acceleration that means if it fails big time you are going to dump a lot of water into the combustion chamber all at once. Water does not compress. When it doesn't something else has to give which is usually a connecting rod, crank, or piston.

As to replacing a head gasket by yourself, it all depends upon how handy and skilled you are.

It isn't rocket science but it is a big job. Unless you have more than two arms it will take more than one person when it comes time to lift the head off and to put the head back down. Not only is head work in a bus a PITA but it is heavy and awkward to boot.

gbstewart 06-08-2015 04:39 PM

Is your coolant going down? is oil level on the dip stick increasing? these are signs of bad head gasket. is the smoke white,or a blueish white?, if you take the oil cap off when its running, is there lots of blow by, meaning lots of smoke blowing out.

Big11beard 06-08-2015 06:14 PM

Gb. This is the kind of questions I'm looking for. I can't be at my bus today but it doesn't feel like blow by past the rings I.e the more I push on the peddle the more smoke pours out. This is push on the throttle and feel the turbo spool and then smoke and the turbo cuts out. Like the engine management opens waste gate and cuts fuel.

opus 06-08-2015 06:40 PM

Is it pure white or blueish? Could be an injector.
Does it smell like coolant.

Booyah45828 06-08-2015 07:24 PM

Does it have a misfire when it starts blowing smoke? Or does it just run out of power? A head gasket is pretty easy to diagnose on diesel because of all the compression all the time. An injector going bad could give you the low power, white smoke, and it will also give a misfire. The bus being new to you, and having these problems will be hard to diagnose because you can't give us any long history to it.

Big11beard 06-09-2015 10:24 AM

The smoke is white and smells bad from what my wife said following the bus home. There is no smoke at all when parked or under light load so it is to be sure. I don't feel what I would feel during a gasoline misfire but you can feel the engine struggle as the manifold pressure increases and starts to smoke.

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