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MD diesel side question.


lbg57
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Finally got the MD I have been working on for several years started & running. 

Runs on the gas side fine, no smoke at all.

When switching over to diesel, it runs but smokes a lot. At about 1/4 open it runs ok but their is a fair amount of smoke. You open it up quickly from 1/4 throttle to WOT and it smokes like a coal freight train for a few seconds then backs off some on the smoke but still a lot.

The injection pump and injectors have been gone through by Central Fuel Injection and has been sitting in a box for the last 5 years.

Air is all bled out of the lines and the pump timing is set at the center mark on the drive gear per the manual. When running and I crack open the injector bleeder it misses bad so the injector should be working correctly, right?

Any ideas as to why it is smoking so much? Is it something in the pump that is not quit right? If I try to adjust the pump timing to either side of the center mark would that clear it up or is their another direction you think I should proceed with this? Thanks.

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The color of the smoke is grey.

 

I checked the pump timing again and it is set to the center mark per the service manual. I have also double checked the flappers and they are seating properly. The valves are all new along with the seats and guides and move freely when pushed down when engine is off. 

Thanks.

 

 

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5 yrs is a long time sitting, from coal train I assume black smoke, could be governor when quickly changing rpm, I would try 2 stroke oil or ATF in your fuel and work it to see if it gets better

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The zero mark for timing is a starting point. The grey smoke is a sign of  late timing. I would advance the timing a little bit. Is it slow to speed up when you advance the throttle? If it is this is another symptom of retarded timing. Don't know what manual you are using but the IH manual says start on the center mark and adjust for the best performance. 

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15 hours ago, kal said:

The zero mark for timing is a starting point. The grey smoke is a sign of  late timing. I would advance the timing a little bit. Is it slow to speed up when you advance the throttle? If it is this is another symptom of retarded timing. Don't know what manual you are using but the IH manual says start on the center mark and adjust for the best performance. 

2x  MB cat had extensive posts here of smoke timing

they are really hard to find and only with an outside search directed back here

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Pump sittin 5 years----NOT a good thing!!! ----- might have to have it freed up again.

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I am working on at pump that has sat may years, a it is terribly gummed up from the old fuel, aside from the plunger being stuck every other check valve in the plunger was stuck.  Where I live we get a lot of bio diesel and it just kill diesels that are not run on a regular basis.  I have the plunger clean, now the distribution block is next, then the primary pump.

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On 8/8/2020 at 9:24 AM, SONNY said:

Pump sittin 5 years----NOT a good thing!!! ----- might have to have it freed up again.

Sitting from a pump shop with test oil in it is much different than diesel fuel. He has a timing issue. 

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On 8/5/2020 at 7:28 PM, lbg57 said:

The color of the smoke is grey.

 

I checked the pump timing again and it is set to the center mark per the service manual. I have also double checked the flappers and they are seating properly. The valves are all new along with the seats and guides and move freely when pushed down when engine is off. 

Thanks.

 

 

zero is the starting point, you need to advance till the smoke disappears. on rev up should have a grey haze only might take 10- 20 degree's of advance. adding a cup of 2 stroke oil to the tank of diesel will help out .

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And if I may add to this ...... Dont forget to put oil in the pump . I got in a hurry once and forgot to put oil in the pump reservoir ....... expensive mistake !!

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