AAZ goes out of timing badly - IDI Engine - VWDiesel.net The IDI, TDI, and mTDI source.

• AAZ goes out of timing badly by haybayian on 03 Jun, 2009 05:59
• Thanks to GolfJetta for his previous answer. It looks that my problem (engine not starting) is that I am out of timing....again. This thing seems to be unable to keep its timing. I will check the camshaft sproket and retorque the bolt. Is there a proper way to do this? My other question is: is there any other reason why this engine should go out of tuning?
  
  Thanks.
  
  Haybayian
• #1 by vanbcguy on 03 Jun, 2009 08:08
• Only way it can get out of time is if something's moving...
  
  I'm assuming you know about the AAZ crank sprocket problems? 
  
  If not, the gist of it is the crank sprocket starts chewing away at the nose of the crank allowing it to move.  I'd bet money an early sign would be timing going out for no reason.  The final result is the pulley breaks off the crank resulting in severe engine damage when the pistons hit the valves.
  
  It's a fairly common problem on AAZ's but it is totally fixable...
• #2 by juleshs on 03 Jun, 2009 08:34
• mine ate itself, i have fixed it now but the pulley doesnt seem to run dead straight
• #3 by burn_your_money on 03 Jun, 2009 10:14
• What was going out of time? The cam/crank of the cam/pump? If it's the crank/cam I'd immidiately stop driving the car and pull of the crank gear and inspect it.
• #4 by 96jetta on 03 Jun, 2009 10:22
• the cam does make 2 rotations. if its 180 deg out your alright.
• #5 by haybayian on 03 Jun, 2009 12:35
• Thank you guys for your insights. As it turned out (so it seems) the camshaft sprocket bolt may not have been torqued properly and presumably  the cam slid out of timing progressively. All seems to be fine for now.
  The VW timing  belt system as well as the interference valves is not what I like best on diesel VWs. But they have other merits.
  Haybayian
• #6 by 88jetta350 on 03 Jun, 2009 13:53
• I'm pretty sure that, due to the high compression ratio, that ALL diesel engines are interference designs.
  
  I know how you feel though, i own gasser VW's as well, and I love how the 8v's can snap a timing belt, and be fine.
• #7 by Golf/Jetta on 04 Jun, 2009 02:37
• "Is there a proper way to do this? My other question is: is there any other reason why this engine should go out of tuning?"
  on your timing, are you tightening the tensioner first, then the cam?
  or the other way around..
  
  what i do is
  
  belt on
  everything almost finger tight
  take the IP lock out
  set tentioner (torque nut)
  check TDC on the flywheel
  tighten the cam with sprocket holder (torque bolt)
  take the cam lock out
  turn the engine over by hand x2
  (must be 4 compression points on a whole revolution)
  x2 light starter cranks without starting the car
  
  belt break in
  retime time after 100 km or so and again after 1000..
  but that’s just me...