replacing injection pump drive shaft bearings - IDI Engine - VWDiesel.net The IDI, TDI, and mTDI source.

• replacing injection pump drive shaft bearings by dave friday on 27 Jun, 2014 15:54
• Hi all,anyone replaced the drive shaft bearings?what tools are needed etc?
  Ta.
• #1 by 410 on 27 Jun, 2014 18:55
• at the very least you need an adjustable reamer for a 17mm bore.  The bushings need a lot of reaming to get to the size of the 17mm shaft.  I would recommend stripping the pump, if you're comfortable with that, and having a shop install the bushings for you.  If you have the right equipment, it's a pretty straight forward job.
• #2 by dave friday on 29 Jun, 2014 01:58
• Thanks 410,the cam belt is starting to move towards the engine,do you know of anything else that would cause this?
• #3 by homerj1 on 29 Jun, 2014 03:12
• Quote from: dave friday on 29 Jun, 2014 01:58

  Thanks 410,the cam belt is starting to move towards the engine,do you know of anything else that would cause this?
  

  
  When I had the same problem last year - it was the ip shaft  - it had a far bit of side to side play.  This thread had a ton of great advice thanks to guys this forum:  http://www.vwdiesel.net/forum/index.php?topic=33735.0
• #4 by sgnimj96 on 29 Jun, 2014 11:46
•  I'm no expert,  but I managed to do the bushings in my 1.6 pump.  
    Here's what I think:  Worn IP bushings cause the timing belt to move away from the pump,  not towards the engine.
      Bushing wear is usually caused by an overtightened belt or just a high miles pump.    
    You have to take the belt off to really check for bushing wear,  you could just loosen the belt but you would need to check the pump timing with the proper tools afterwards.
     You can physically see serious bushing wear by pushing on the sides of the IP sprocket (for leverage)
  
  To do a bushing job you first need to know how to completely disassemble and reseal your pump (cleanly).
  
  Actually pressing the bushings out,  back in, and reaming them out is a whole nuther can of worms.   Most people don't do this themselves but I managed to make a puller and did the job with a single adjustable reamer.    I definitely needed a bench vice to hold everything steady,  and it took a while.      
• #5 by libbydiesel on 29 Jun, 2014 13:16
• Loosening and re-tightening the timing belt will not affect injection pump timing.  Even removing the belt entirely and then re-installing the same belt will not change the timing.
• #6 by fatmobile on 29 Jun, 2014 14:31
• Good point though; if the bushings wear,.. the belt tracks away from the pump.
   As loong as it doesn't keep getting closer to the pump (not sure how that could happen) you have no problem.
   Actually running a little closer to the pump makes the belt track better on the other pullys/idler.
• #7 by dave friday on 29 Jun, 2014 14:48
• Well,well,well!..earlier today I was pricing up a replacement pump [£650] but thought I'd check the cam belt path..
  So following the advice from here I gave the pump cradle a push down and bingo the belt runs in the middle of the cam and pump wheels!
  Thanks everyone.
• #8 by dave friday on 29 Jun, 2014 15:00
•  There is a bit of rock on the drive shaft and some in and out play,when I adjusted the cradle I moved it up first, this brought the belt very close to the engine almost touching the captive nut that the dip stick bolt screws into.