read the post about getting ready for winter and changed fuel filter and drained the water separator. I have a full tank of fuel. The plastic drain plug in the bottom of the water separator broke off so I had to pull it apart to remove the rest of the plug. I live in the sticks so a 5/16" bolt replaced the plug until I can get a replacement plug. I pumped up the system with the manual pump and it started o.k. I started up an incline and it died, got it stated and it runs but it surges up and down around 1700rpm . I bled the injecters and got fuel spraying .This engine ran great till I changed the filters, Do I have air somewhere in the system, and how do I bleed it out? I hate falling back when I should be rolling forward! Thanks for any help 1996 Cat 426B Perkins engine