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dsm56

Simplicity 7790 Diesel Tractor

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dsm56
I was told that "all diesels smoke when started" when I inquired about the condition of the engine on a 7790 diesel tractor. I thought that the this indicates that the fuel rail needs adjustment, or that the rings are worn, but a healthy diesel will not smoke on startup. Can anyone comment on this? Thanks, David

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UCD
Mine smokes on start up and has always smoked from new. It has to do with the fuel air mixture and cyl.temp at startup. There is no fuel rail on these engines. Just an air intake manifold and 2 fuel injectors mounted directly into the heads. The fuel/air mixture can be controled to some extent by the spacers in the injector pump. A dirty Air filter will make them smoke all so.

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All diesel engines will start with black smoke and this will end when the cylinder temperatures rise. If they start with white or blue smoke this indicates engine wear or several other problems related to gaskets, heads, engine blocks and water in fuel. :)

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BLT
Depends on what type of injection system you have. Some will smoke white or blue for a bit when cold. I would be more concerned when engine is at hot idle and it smokes blue or white. That indicates generally low compression.

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BLT check with Chilton's Diesel Guide by James Joseph. I have a 7.3 litre Navastar V8 in my ford truck, if this engine ever started with blue or white smoke I would have a problem on my hands. I have seen Fords in dealers truck lots that do this and that's why they are there. The cost to overhaul these engines is $7000.00 and up Canadian. ;)

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arnoldir
I've got a brand new Excursion with the 6.0 Power Stroke Diesel and when she starts for the first time in the morning I get a puff of blue/grey smoke. The 2 cyl Lombardini on my Magnatrac Excavator has only 32 hours on it and has always smoked a bit whan started. Just my 2 cents

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UCD
But we are not talking Big truck or car liquid cooled engines we are talking about a two cylinder air cooled diesel with out glow plugs. These have a heated air intake manifold and a simple injection system People that don't understand these engines spread a lot of old wives tales. The thing that is true is you don't have carb. problems, no ignition problems, no points or condenser to mess with or fouled or bad spark plugs no bad plug wires or shorted out ign. switch. Just use good oil and keep it changed and use good fuel and they will run for a loooooooooooooong time. Mine has been running for 18 years with no problems and it has been used long and hard and put away wet.

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You are right UCD we do not want to spead old wives tales. The inventor of the diesel engine was Rudolf Diesel in 1893. The theory and principles of the diesel engine have not changed, therefore the diagnosis to understand problems with this engine have not changed. To get a very good understanding of this engine and to diagnose it's problems with accuracy I suggest reading Chilton's Diesel Guide by James Joseph. There are many good books on this subject and one of my favorites which I have read is the above. PS Diesel's first engine was one cylinder and the fuel was powdered coal. 8D :D

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dieselman
My lombardini in my 920 that i built is brand new and it smokes when started. We have lots of Diesel tractors on our farm and they all smoke a luttle bit at start up in the morning. They dont smoke quite as bad as the lombardini due to a better injection system. Also some of them have a Turbo which i think makes some diffrence. like someone said if it smokes blue when ideling after it has ran along time can may be mean bad rings. but also loss of power and hard starting comes with that. Our 1066 IH is turned up allot from factory 125 to about 150 and it smokes no matter what but it starts righ up and has plenty of power (will run all over some 4430's) so it depends really on the engine.

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bigcountry
Yeah, all diesels will smoke upon startup, even new. You oughta see when we crank up the 3208 Cat in the dump truck in the winter. I can't see or smell anything else for about 3 minutes.

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rokon2813
I know this doesnt belong here but I ran that "7.3L powerjoke" over the road for 7 years. Even when new they always smoke a little at startup. As for the "cranktwister" I worked for a company that had about 200 of them leased on and never saw a crank problem. By the way I retired one with 650,000 miles and another with 801,000 and neither engine had ever been opened for anything more than 1 oil pump and 6 injectors between the 2 of them.

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