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Engine Specific Info and Questions => IDI Engine => Topic started by: Maarten on September 17, 2007, 12:47:22 pm

Title: Problems timing the pump
Post by: Maarten on September 17, 2007, 12:47:22 pm

Since I rebuild my 1.9TD AAZ engine (and sat in a corner for ~1.5 years) I found a vanagon to put the engine in, the conversion was a lot of work but I completed it :)

but... I can't get the pumptiming to spec.

Flywheel set to TDC
Cam locked with plate and adjusted to center with shims.
Pump lockpin inserted

then I used this how-to (and some other, always come to the same result)

http://www.vwdieselparts.com/injtim.htm

Coldstart lever is pushed in
Flywheel at TDC lock pin inserted, gauge inserted at 3mm.
Turn back until the needle stops, pull out the gauge until small needle shows 1mm, big needle at 0

Turn forward till TDC.

Reading is somewhere between 1.80 (pump max away from head) and 2.40 (pump closest to head).

It idles ok but when running under load it produces load knocking so that must tell that the timing is off badly.

I think it pulls ok (in a 1500kg van, last car the engine was in was about half the weight)

I have done a governor mod with stiffer springs and some more fueling, nothing more.

Any ideas about this strange problem?

Title: Problems timing the pump
Post by: Maarten on September 17, 2007, 01:13:56 pm

mmh.. seems that more how-to's on internet have the same error:

http://vwdiesel.net/phpBB/viewtopic.php?t=10269

there Vincent Waldon mentiones that there is an error, after turing forward to TDC it should be "reset gauge to 0 with both small and large needle at 0?

Title: Problems timing the pump
Post by: Vincent Waldon on September 17, 2007, 08:55:23 pm

I just find it easiest to set the gauge to 0.000 once it stops moving as you turn the engine counterclockwise.... you then turn the engine clockwise to exactly TDC and read the timing value without any further math required.


Vince

Title: Problems timing the pump
Post by: Maarten on September 19, 2007, 02:02:47 am

I just rechecked the timing, it was spot on 1.00mm (I set the pump where I tought it idled the best).

To find a solution for my dieselknock I set it to 0.90, knock still loud. Swapped the GTD single spring injectors for the original AAZ injectors, knock is still there...

any ideas to get rid of the loud knocking?