AAZ pump modification - page 1 - IDI Engine - VWDiesel.net The IDI, TDI, and mTDI source.

• AAZ pump modification by Hey on 14 Mar, 2009 07:40
• Hey guys... I made a little WORD or PDF document to explain how you can get more with your AAZ pump (it also hold for 1.6td pump as well).
  
  
  http://www.vwdiesel.net/forum/index.php?topic=18852.0 [link fixed by mod]
  
  The only thing left to know is that if you want to have a:
  
  10mm head you need:
  1.6td regulator + AAZ advance system
  OR
  1.9td regulator + tdi   advance system (maybe a shim or 2 for the advance system)
  
  11mm head
  1.6td regulator + tdi advance system
  
  
  Have fun ... and report your results!
• #1 by dts67 on 14 Mar, 2009 07:52
• Thanks man!
• #2 by Hey on 14 Mar, 2009 07:59
• OH!! I forgot to mention that it is in FRENCH. So use the traductor button of word!!!
  
  
  Sorry but I don't have time right now to translate. If someone else is interested... no problem!
• #3 by Dirtrag2 on 14 Mar, 2009 08:27
• Very nice, Merci dude :!:
• #4 by rallydiesel on 14 Mar, 2009 09:26
• I understand the second section (adjusting the internal pump pressure for the dynamic timing advance), but I don't really get the first section. Are you adjusting the boost pin to get full travel at full throttle? Are you actually removing those balls from the housing and how do you do that?
• #5 by Hey on 14 Mar, 2009 12:41
• Quote from: "rallydiesel"

  I understand the second section (adjusting the internal pump pressure for the dynamic timing advance), but I don't really get the first section.

  
  
  That's it.
  
  

  Quote

  Are you adjusting the boost pin to get full travel at full throttle?

  
  
  That is pretty much it! Sometimes people just use a 1.6td cover that doesn't have the lever you need to cut.... but they forget to adjust the full travel with the adjusting screws.
  
  

  Quote

  
  Are you actually removing those balls from the housing and how do you do that?

  Yes... you need to do this only if you want to change the boost pin o-ring.
  
  To get the balls out of the housing, you need a hammer, a sharp punch and some precision!
• #6 by rallydiesel on 14 Mar, 2009 14:21
• So would it be better to use the 1.6TD spring with the 1.6TD pin or is the 1.9 spring fine?
  
  And what do you mean by regulator and advance system? Do you mean the boost pin and the governor assembly or the internal pump pressure valve?
• #7 by Hey on 15 Mar, 2009 08:45
• libbybapa is right.... at about 5psi the 1.9td spring is compressed... it may result in higher fumes. Also the 1.9td pin is NOT machined aggressively. So it won't give you maximum fueling and maximum timing advance.
  
  You may use a 1.9td boost pin, but use a GRINDER to machined the pin to have maximum throttle travel. Just put the boost pin in the hole without the spring, and move the throttle with you hand... if you feel higher resistance before you get to the adjusting screw (maximum travel), grind a little bit more.
  
  

  Quote

  And what do you mean by regulator and advance system? Do you mean the boost pin and the governor assembly or the internal pump pressure valve?

  
  I mean the internal pump pressure valve.
  
  
  The regulator is shown in the last figure of the document. It adjust the internal pressure so the timing advance is always correct. Different regulator have different springs stiffness and different hole size.
  
  The advance system is a cylinder that travels toward the radiator as more timing advance is given (front of the pump) and as pressure build up inside the pump. It is situated in the middle-bottom of the pump. There is two cover for this cylinder. THe first one is at the back of the pump where the cold start lever is bolted. The second one is at the front where the solenoid is situated.
  
  On an AAZ pump there is 2 springs, on a tdi pump there is only 1. Not the same length, different springs also.
• #8 by rallydiesel on 15 Mar, 2009 10:36
• How does the boost pin affect timing?
• #9 by carrizog60 on 15 Mar, 2009 15:51
• Does the 1.6 pump also needs to be adjusted on the pin travel?
  were did you get the info on the adjusting the governor like that(location of the bolt)
  and the pressure in mm?
  
  
  thanks for sharing!
• #10 by Hey on 15 Mar, 2009 18:30
• Quote

  How does the boost pin affect timing?

  
  
  The boost pin limit the throttle lever movement. That means that it also limits the governor sleeve which changes the timing with injection quantity.
  
  Having the front solenoid to 12V is the equivalent to having the maximum timing all the time. On a very well adjust pump, you can't put 12V on this solenoid since the engine will clater too much at low load.
  
  That means that if you can put 12V at this solenoid and continue driving it, it is because you don't have enough timing advance with RPM (regulator incorrectly adjusted)
  
  
  

  Quote from: "carrizog60"

  Does the 1.6 pump also needs to be adjusted on the pin travel?

  
  
  On a 1.6 pump, there is no pin I think, so the only thing to adjust is to make sure the stop screw for maximum throttle lever play is correct. You will feel a "resistance" (governor spring) when you get to the maximum position.
  
  Tintin once told me to adjust the regulator 0.5mm at a time. For the governor adjustment, you can very well test it yourself. IF you screw it far you will hear the engine clatter too much at ½ throttle position... then you back up until it seems perfect.
  
  For the other things... I read, try and ask. My job is research... this is why I like injection pumps!
  
  Also, when I say something I am not sure, I mention it. When I already tried it and it works I try to explain to others.
  
  If you tried anything I mentionned... report here in this post!!
• #11 by rallydiesel on 15 Mar, 2009 20:29
• I'm sorry, I don't get it. Are you just saying that the boost pin controls full fueling, which controls max. pump rpm, which controls advance?
  
  Also, you said to put 12V to the advance solenoid in your write-up. But now you said to keep it connected? Can you clarify this?
• #12 by Hey on 16 Mar, 2009 06:25
• Quote from: "rallydiesel"

  I'm sorry, I don't get it. Are you just saying that the boost pin controls full fueling, which controls max. pump rpm, which controls advance?

  
  
  Yes! THere is a sleeve with a calibrated hole that slides on the governor axis. When you put the pedal to the floor, if the boost pin allows it, you will have maximum travel of both the throttle lever and governor sleeve. At maximum travel the hole on the governor sleeve is completely closed and the internal pressure goes up... resulting in more timing advance.
  
  

  Quote

  Also, you said to put 12V to the advance solenoid in your write-up. But now you said to keep it connected? Can you clarify this?

  
  
  I never said to put 12V... in fact DON'T do this! I only said that IF you do it with a correctly adjusted pump, the engine will clatter too much and won't be drivable.
  
  I'm sorry if I induced people in error on that point.
• #13 by rallydiesel on 16 Mar, 2009 07:33
• Quote from: "Hey"

  
  Yes! THere is a sleeve with a calibrated hole that slides on the governor axis. When you put the pedal to the floor, if the boost pin allows it, you will have maximum travel of both the throttle lever and governor sleeve. At maximum travel the hole on the governor sleeve is completely closed and the internal pressure goes up... resulting in more timing advance.
  

  
  
  That's interesting. Is the governor axis you're talking about, the shaft near the top of the pump with the spinning weights and that sliding sleeve that pushes the middle part of the throttle levers? I always wondered if that had another function than just limiting high rpm.
  
  I have another question for you. Where exactly is the internal pressure regulator located in the fuel flow. To me, it looks like it is after the vane pump. But when pressure exceeds the valve, where is the fuel routed? It looks like it goes back to the "in" fitting?
  
  Thanks for your input.
• #14 by Hey on 16 Mar, 2009 20:27
• Quote

  That's interesting. Is the governor axis you're talking about, the shaft near the top of the pump with the spinning weights and that sliding sleeve that pushes the middle part of the throttle levers? I always wondered if that had another function than just limiting high rpm.

  
  
  I am happy yo find It interesting!/ Yes / In fact there is 3 functions to that sleeve/axis/spinning weights.
  
  The third function is to make sure the idle AND RPM is constant. At idle a very small spring is stretched (the one you need to detach when you remove the cover). On a 1.6td pump or cumins pump (and many other), the small spring is ON the throttle lever. At higher RPM the smallest (in term of rigidity) of the throttle lever spring comes into action... and at very high RPM some people call it the governor mod spring... which regulates the maximum RPM.
  
  
  

  Quote

  I have another question for you. Where exactly is the internal pressure regulator located in the fuel flow. To me, it looks like it is after the vane pump. But when pressure exceeds the valve, where is the fuel routed? It looks like it goes back to the "in" fitting?

  
  
  Yes, but just in part. In fact, there is always much more fuel pumped inside the pump since the regulator only have small "evacuations" holes. So even if this small part is re-routed to the entrance, fuels keeps coming out of the pump and fuel is still coming in the pump as well.
  
  IT is easier with an image... look page 6/30 of the pdf document.
  
  
  
  
  feel free to ask any other question.