A tale of woe: 300 tdi fuel injector pump

[cypermethrin]

The head seal on my Bosch VE fuel injection pump has been leaking for a while; having read the internet on the potential of fixing it in situ with a nitrile seal I set about the task.

it all went well - right up to the point where it was all refit, primed and ready to turn the ignition . Engine cranks on the starter - no firing.

poop - checked the pump was getting fuel and the stop solenoid had voltage and tested it on the bench all good.

However, despite checking and rechecking i just cant get any fuel through the pump and out of the injectors. i fear the worst.

so now I have to do what I should have done at the start which is remove the pump and get my local diesel specialist to rebuild it.

 

Before I do the removal is there anything else I should check for ? i have not touched any of the timing or any electrics - but its evident the fuel is not getting out of the pump and into the lines. 

 

If if do need to remove it is it a matter of just undoing the three bolts (not the big centre one) behind the insepection hole on the crack case and then the three bolts holding the pump to the case ? how do I ensure I dont destroy the timing ?

 

thanks in advance its been an eventful and painful weekend

 

tim

[cypermethrin]

Removed the fuel stop solenoid again and refitted it without the plunger

Same result - engine turns over no firing, no fuel being pumped out of injector - 

so must be a goosed fuel injector pump - right ?

[lo-fi]

Unless you've managed to get an air bubble somewhere that's not quite bled. Did it bleed easily enough after you put it back together? 

[oneandtwo]

I’ve posted about this before but you can get an airlock in the pump if the tiny bleed hole is blocked in the return line banjo bolt at the top rear of the pump, which cause the exact symptoms you have - no fuel reaching the pump head / fuel solenoid.

Try removing this banjo bolt from the return line fitting on the pump and turning the engine over, this will bleed air from the pump if the hole or integral filter s blocked and hopefully engine will start. Hole in banjo bolt can be cleaned out with a strand of wire.

 

Edited April 15, 2019 by oneandtwo

[cypermethrin]

Thank you both for your help and suggestions.

i am stuggling to identify the "the tiny bleed hole is blocked in the return line banjo bolt at the top rear of the pump".... is this it ?

thanks

 

https://www.paddockspares.com/mjn100910-fuel-spill-return-pipe-300tdi.html

 

 

[western]

No thats the spill return pipework.

 

the small hole is in the banjo bolt shaft,

[dailysleaze]

 

[cypermethrin]

So am I looking for the banjo bolt shaft of the return spill lime or something else.... sorry if I am being dim...

[western]

Yes also check all the bolts at each injector just to make sure the small holes are clear.

[Peaklander]

They are referring to this banjo bolt mounted at the back of the pump. It’s in the dark part of the photo but you can see it under the throttle linkage.

It takes a 17mm socket and has a flexible spill pipe from the cylinder head and a short rigid pipe that joins the return all the way back to the fuel tank. 

[cypermethrin]

Thanks guys - thus is why I love this forum

[cypermethrin]

Update - and good news  - you guys were right it was an airlock in the pump

Now runs sweetly and no leaks - massive thank you to all those that have helped - greatly appreciated

 

tim

Edited April 18, 2019 by cypermethrin

[Gazzar]

Hurrah!

[oneandtwo]

7 hours ago, cypermethrin said:

Update - and good news  - you guys were right it was an airlock in the pump

Now runs sweetly and no leaks - massive thank you to all those that have helped - greatly appreciated

 

tim

Bleed hole has probably been blocked for years - it’s only when the pump is drained down of fuel that it becomes an issue.