no diesel out of injector lines after pump rebuild

[regcheeseman]

I swapped the pump head over on my AAZ pump, from the tdi 10mm back to the original 9mm head.

Trying to prime the pump and I just get a slight spurt from two injector lines and nothing from the other two.

with the lines tightened, there is not enough for it to fire on two. it has a go though.

I used some blobs of grease to hold bits in place when I fitted the head and timed it up to 1.00mm on the bench, could the grease have blocked some bits up?

Or maybe the delivery ports are stuck?

I didn't touch the fuel screw, maybe there is just no delivery?

Any ideas?

I'm hoping the diesel in the pump will wash the grease out (or dissolve it a bit) if I leave it overnight....

[R.O.R-2.0]

if its only coming out of 2 ports, i would suspect that the pump is not filling properly, or the stop solenoid is messed up..

[Mark(The Miser)UK]

Check that internal pump pressure is building,Use a gauge, or check   xs will be squirting out of  out bolt.
Remove timing belt and crank pump with a ratchet. Feel for pressure build up.   A correctly working pump willl act as a 4 way pop tester, and resist accordingly

[Wayland]

How long did you work at it? I had a pump that had been drained and stored for several years. I primed it up, but it still took lots of cranking to get  any fuel out the delivery valves.

[regcheeseman]

Mark, the vane pump should be working fine after me stripping it and rebuilding it last week - yes it did run after.

How long did you work at it?

Far too long. I pressure fed the pump with a litre of diesel, then I hooked it to a raised aux tank (hanging from ceiling)
Then I hooked the vehicle up to a big toyota diesel battery with lorry leads - it span over very fast for several minutes.

It's physically trying to pump in that the timing gauge lifts as you would expect.

I'm thinking that the spill collar may not be sat in the throttle lever properly, but then why would two lines show diesel and the others be dry....

[Mark(The Miser)UK]

Try swapping over those aux delivery valves. See if the problem follows the valves.
They are so simple in operation, only wrong assembly should interfere with their operation.

[regcheeseman]

The delivery valves were the only things I didn't swap over, they were already in the head so I thought, 'leave them in as they are at least the right type'

[Mark(The Miser)UK]

Someoe else had a similar problem some months ago. Alas I don't remember the outcome... No harm in unscrewing and checking outputs for crud, flow etc.

[regcheeseman]

The moral is - look for the simple things first.....

The injector unions were all open 1 and 3 were bone dry, 4 and 2 wet but not a decent spurt.

Strangely 1 and 3 are at the top of the head - maybe a clue?

I pull 1 and 3 delivery ports, nothing obvious, but I swap them with known good ones of the same spec.

still nothing when cranked.

now I'm thinking about pulling the pump again but figured I'd try something - what is there to loose?

So I slacken the locknut on the fuel screw and think hell I'll give it 3 full turns.

I crank the motor without allowing any glow, it straight away fires up on two and sprays diesel everywhere from the slack 1 and 3 unions.

unions tight and it's away!

The clack is gone and there is much more low end power. A whiff of soot at full throttle (no boost pipes fitted), steady idle and revs like a good'un.


YAY!

[ORCoaster]

So how did the fuel screw get out of adjustment to the point of ubber lean?  And you were driving it prior to fill up?  Very odd.

[rabbitman]

Whenever I have an IP opened up and have lost the settings I screw it in so I KNOW it'll inject fuel. If it runs away you can just shut it off and readjust things.

[regcheeseman]

So how did the fuel screw get out of adjustment to the point of ubber lean?  And you were driving it prior to fill up?  Very odd.

I was driving it with the 10mm head but I don't remember leaning the screw off for the 10mm head.

When I fitted the 9mm I backed the screw out 5 complete turns to make refitting the pump top easier - I always do this and it's always 5 turns and I alway turn it back in 5 turns.

I'd got mislead on my diagnosis, because 2 port delivered and 2 ports were dry I thought that id wouldn't be fuel screw as I would have expected all ports to deliver - but just not very much.

[ORCoaster]

I hate getting distracted with something else when I am in the middle of a "process"  glad you got it back on the roll.  And may have helped others with possibilities when they almost have it running.