Is my pump worn? - IDI Engine - VWDiesel.net The IDI, TDI, and mTDI source.

• Is my pump worn? by molgrips on 03 Nov, 2008 03:59
• I just re-checked my timing, was going to experiment, and I noticed that each time I set it, I re-checked it and got different results by about 0.3mm
  
  Does that mean something's worn and sloppy in there or what?  Or is that normal?
• #1 by Mark(The Miser)UK on 03 Nov, 2008 16:30
• Quote from: "molgrips"

  I just re-checked my timing, was going to experiment, and I noticed that each time I set it, I re-checked it and got different results by about 0.3mm
  
  Does that mean something's worn and sloppy in there or what?  Or is that normal?

  
  Simple test; do your timing measurement from the usual clockwise rotation, then rotate crank 720 degrees remeasure. Then compare with 360 degree rotation, finally  rotate anti clockwise repeating experiment. All clockwise readings should be the same, and all anticlockwise equal also.
• #2 by molgrips on 04 Nov, 2008 01:50
• Quote

  All clockwise readings should be the same, and all anticlockwise equal also.

  
  
  Thanks for the tip - I will do that next time.. but what if the readings are not the same?  Would this just mean my measuring tools are not very good, or could it be a pump fault?
• #3 by Mark(The Miser)UK on 04 Nov, 2008 15:49
• I dunno either  :wink:
  
  How about the pump's  cam lobes uneven. Surely they wear :?:
  ...Chicle or some other crud under a section of timing belt :lol:
   
• #4 by Vincent Waldon on 04 Nov, 2008 17:20
• I find that if the adapter is not threaded in really tight or if the dial indicator is not attached to the adapter super tight the numbers can drift a bit.
  
  And of course there's the most common problem... the adapter extension sticking a little bit.
  
  I tend to "help" the spring in the dial indicator by pressing down on the upper stem of the dial indicator... often that's all it takes to click into place.
• #5 by Mark(The Miser)UK on 04 Nov, 2008 17:40
• I agree with Vince....
  And  Andrew :wink:  
  
  Heck, I even agree with myself a little :roll:
• #6 by molgrips on 05 Nov, 2008 02:44
• Having had a little play with the dial and adapter, I think Vince is on the right track. At least I hope he is, who knows what my pump is like inside especially after all the various different fuels that've been through it