Diesel Locomotive Parts ID

Welcome, Brian! I can't help with your specific question, but I'll move your post to where it will be more likely to be seen by qualified diesel maintenance personnel.

Moderator's Note: moved to General Discussion: Locomotives, Rolling Stock & Equipment.

This may not be any use to you, but a website worth remembering:
George Elwood has a HUGE railroad image site, Fallen Flags, with in one section a selection of manuals for locomotives:
http://gelwood.railfan.net/manual/manual.html" onclick="window.open(this.href);return false;

For legal reasons (I think: EMD apparently thinks things like operator's manuals are proprietary) it doesn't have much that's up-to-date, but there are both sevice manuals and parts catalogues for a number of historic (1960s-1990s) EMD locomotives.