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  • EMD FUEL SYSTEM

  • Discussion of Electro-Motive locomotive products and technology, past and present. Official web site can be found here: http://www.emdiesels.com/.
Discussion of Electro-Motive locomotive products and technology, past and present. Official web site can be found here: http://www.emdiesels.com/.

Moderator: GOLDEN-ARM

 #1434338  by chromeliner
 
With the EMD 645 Series, the amount of fuel delivered is governed by the rotative position of the injector plunger. I have been told that to adjust the rack from 96 to 98 results in a significant fuel saving.

If this is so, then how far can the rack be adjusted without interfering with the normal operating conditions of the engine?

I.E. How far can you restrict the fuel and still have the engine running smoothly?

Thanking you in advance for your interest. Chromeliner.
 #1434372  by RickRackstop
 
You seem to be confusing the 645 Diesel with a spark ignited engine where you have to maintain a correct air fuel mixture. All 645's are controlled by a governor where the engine speed is set and if the load varies the governor varies the fuel to maintain the set rpm. For instance on a blower engine if we set rpm to 750 rpm that sets the amount of air supplied by the blowers. If the load increases the governor will increase the fuel just enough to maintain 750 rpm'.

Resetting the rack stop from .96 inches to .99 inches on a 16-645-E will reduce the maximum horsepower from 2000 to 1950 and yes, you will save some fuel
 #1434578  by chromeliner
 
Thank-you RickRackstop. That was the reply I was wanting. Now, with that in mind, how much further can the rack stop be adjusted to lower horsepower and save fuel?