[Vwdiesel] weepy injector

[LBaird119 at aol.com]

In a message dated 3/15/2006 4:19:13 PM Pacific Standard Time, rbp at 4u2bu.org 
writes:

> what might fail in a VW injector?
> before I tear into and rebuild the little bugger, any suggestions on  
> where to look?
> anyone know what's vulnerable to (back) pressure (through inj return  
> ports) in there?
> 


  The pump, driveability and leaks at the jonts are the main things that 
would be affected by back pressure in the retun line.  There's nothing 
in the injector itself that would be affected.  The pump uses the internal 
pressure to regulate injection volume so back pressure would mess 
with that and most return line junctions are just pressed and not clamped.
  First you need to find the leak.  Some brake cleaner, carb cleaner or 
such and compressed air is great for this.  Hose off the injector, blow it 
off, run it and see what leaks. 
  It could be the high pressure line, the returns, or the body joint.  If 
it's the 
high pressure line then try tightening it a little but usually it's from 
being 
overtightened too many times and the tapered fitting is mushed too far and 
the line/s need replaced.
  If it's the return hoses, it could be the wrong hose being affected by the 
diesel fuel. I've had the nipples cracked and also simply leak where they 
are pressed into the upper injector housing.  
  If it's between the body halves you have to disassemble the injector and 
lap the joining parts that make the seal;  the upper section, a 1//4" thick 
middle section (both sides) and the injector nozzel.  Don't mess with the 
nozzle!  A little 400 wet/dry on a machined surface or glass with oil will 
clean up the three surfaces quite nicely and quickly.  Clean well and 
reassemble.  This is pretty well a must whenever replacing injector 
nozzles.
     Loren