250 CE green injector / einspritzventil 0 280 150 004 investigation

Dear all,

Since I joined this forum, this picture ( Image 2 of 6) by Volker
jetronic.org/de/d-jetronic/einspritzventil#
has interested me. I've always wondered what an injector looks like from the inside. 

To find out, I dismantled two stuck injectors. I completely dismantled the first one to see how it was crimped, and then I invented a small handy tool to try and remove the upper part without completely destroying the housing and connector.

The second picture shows the completely destroyed green connector and housing.
The first picture shows the tool in action, with the upper part positioned under the collar of the fuel intake line and the lower part resting on the original steel retaining ring.
The third picture shows the loose parts of the tool.
The last picture shows a nicely opened outer housing at the top and a complete intake line with coil and connector.

Ps. 1: In the last picture, you can see some sealing residue that had accumulated in the center section.
Ps. 2: The injectors can indeed rust from the inside, and rust residue accumulates in the center. This is trapped between the intake filter and the top of the needle.

Kind regards,
Marc

 

Hi Marc,

this is really a very interesting tool.
Did you succeed in separating the upper part (coil, support and plastic body)?

The one problem are stucked injectors.

The other problem are leaking injectors.
To get them tight again, you have to replace all seals.
For this, the upper part must also be dismantled.

Did you already try this?

Regards
Norbert

Ps.: Does the upper part of the tool fit the injectors with two sealing edges, too?

Hi Norbert,

To answer your questions:
Did you succeed in separating the upper part (coil, support and plastic body)?

No i did not. But i (or anybody) also can not do that i believe.
My best guess is that Bosch first assembled the little seal onto the bottom part of the fuel injector steel top part. Then assembled the complete coil (is coil with the plus and minus connector) and bend the connectors in the correct direction and then put this small assembly in a plasttic injection mold and overmold the top part with a green plastic.

For this, the upper part must also be dismantled.
Did you already try this?

Probably you mean lower part. No i did not do this yet.

Ps.: Does the upper part of the tool fit the injectors with two sealing edges, too?
No it will not fit.

Ps 
I believe the following phenomena can occur:
1) Leaks
2) Stucked needles
3) Flow rate too low
4) but also flow rate too high, which I've experienced myself.

Greetings Marc