Dismiss Notice

Welcome To CK5!

Registering is free and easy! Hope to see you on the forums soon.

Score a FREE t-shirt and membership sticker when you sign up for a Premium Membership and choose the recurring plan.

Injection Pump Timing

Discussion in '1982-Present GM Diesel' started by fbronson, Jun 11, 2004.

  1. fbronson

    fbronson 1/2 ton status

    Joined:
    Jan 12, 2004
    Posts:
    104
    Likes Received:
    0
    Location:
    Denver, CO
    I've seen a few posts regarding the timing on the fuel injection pump. Forgive me for being a bit naive, but where do I find the pump? And how do I adjust it? I've looked for it a little, and can't seem to easily find it. /forums/images/graemlins/confused.gif
     
  2. imiceman44

    imiceman44 1 ton status

    Joined:
    Aug 5, 2002
    Posts:
    15,160
    Likes Received:
    1
    Location:
    Sacramento, CA
    [ QUOTE ]
    I've seen a few posts regarding the timing on the fuel injection pump. Forgive me for being a bit naive, but where do I find the pump? And how do I adjust it? I've looked for it a little, and can't seem to easily find it. /forums/images/graemlins/confused.gif

    [/ QUOTE ]

    Well the best thing you can do is buy the haynes manual for diesel engines, it will make it easier for you to know at least what each part is but for now, the pump is actually in the valley under the runners of the intake.
    I hope that was clear enough to help you find it.
     
  3. AgDieseler

    AgDieseler Certified Scrap Producer Premium Member GMOTM Winner

    Joined:
    Jan 25, 2001
    Posts:
    1,038
    Likes Received:
    1,106
    Location:
    Dallas
    The timing is adjusted by physically rotating the body of the injection pump either to the passenger side (retard) or to the driver side (advance).

    The "good old boy" method relies on the relationship between the two timing marks on the front cover and the pump body itself. Some people say that about 1mm equals 2 degrees of advance. I say that our diesels are so sensitive to cylinder pressures that guessing at a precise timing figure isn't wise.

    There are a few different meters available from Snap-On, Ford Rotunda, and a few others. The most accurate method is to use a luminosity timing meter such as the Snap-On MT480 or the digital MT1480. A sensor threads into the #3 glowplug hole and actually views the combustion event. A magnetic probe detects an indentation on the harmonic balancer. The two are compared and a timing result is achieved.

    With the timing marks perfectly aligned, and assuming that there is no slack in the timing chain, TDC should be at 1400 RPM. Leave it there for moderate power, and low NOx levels. Advance the timing to about 3-5* BTDC anywhere from 1300-1500 for more power. Several factors influence which timing mark is best for you. Is your engine: Turbo-ed? Non-turbo? What's the fuel rate? What's the injector pressure? How much timing chain slack is there? (you really should be running DSG gears anyway!)

    I've got a full writeup about halfway finished that covers what timing does to engine performance, efficiency, and emissions, and gives a practical tuning application using the MT480 on my truck.

    I know that's a lot, but this really is a cornerstone in maximizing engine performance.
     

Share This Page