Needle Valve Check: Disassembled Condition

Hello everyone!

I would like to know if it is possible to test a new hydraulic generator (NHG) even when it is already assembled. I am familiar with the "tapping test" that is useful when the generator is installed, but it doesn't help much when the unit is on the workbench.

Best regards,
glimmer

Hi,

It's impossible to reliably test the NHG unless you drive around in a car. The device might work perfectly for an hour, and then suddenly stop functioning for a few seconds.
Checking the engine control unit's fault memory is the most effective way to diagnose the problem.

Edit: Technical article about the needle advance mechanism, https://community.dieselschrauber.org/en/viewtopic.php?t=26339

Best regards, Rainer.

That's a shame... I guess I'll have to figure out the installation and testing myself. Thanks for the reply!

schimme wrote:

That's a shame... then I'll probably have to find a way to install it and try it out. Thanks for the answer!

How about connecting the NHG to the cable, turning on the ignition, and logging into the engine control unit?
This should be sufficient as a preliminary test.

However, a resistance test can also be performed in a simpler way .
"Furthermore, I believe that NHGs are more likely to fail due to mechanical problems than electrical ones."

I performed a resistance test on my faulty NHG (fused disconnect switch) – the error code indicated a short circuit after the positive terminal – but I couldn't detect any difference.
What does a mechanical failure look like in a new car?

Something might be stuck or broken... This is roughly what the inside looks like.

...or it could simply be an exposed (uninsulated) section of the cable.

I have a question about that too.
Does the NTC resistor provide a resistance signal, or is it positive or negative?
I'm asking because I just installed a new one myself.
The Aber of the new generation had a different plug adapter, costing 80 euros.
I quickly modified the plug.
Now, I've mixed up the cable connections on my old device, and I'm not sure which cable goes where.
Is there a way to measure that?
The connector indicates +/- for the cables, but unfortunately, both cables are white with no markings.
I would like to keep it as a spare part, as the injector nozzle was still okay after the pressure test.
Oh, I swapped them out because two of the nozzles were damaged.
Best regards,

Okay, I'll dig that thing out. I unfortunately have the NHG without the connector housing, and I really don't want to connect it with the wrong polarity.

How will you distinguish between the two wires?
Both of them are, in fact, the leads of the same coil.
hg
Herbert.

Since it's white, there's nothing visible. Therefore, it seems like it doesn't matter.

marson wrote:

Since they are white, there is absolutely none.

Therefore, it seems that it doesn't matter? }
It shouldn't really matter, but the effort required for a test drive to try it out is manageable, as there are only two possible options.

Testing without a car requires an oscilloscope, a power supply, and a clamping device, which probably wouldn't be worth the effort.