AFN, spark plug, stripped threads, help!!!

hello,

I wanted to change the spark plugs today, but the fourth one got stuck, even though I could turn it. I can't get it out anymore. Do I have to remove the entire head for the repair? What repair kits are available for that?

Best regards.

Ouuuuuh, that's crap.

Normally, the spark plug needs to be removed completely to properly verschandeln out any remaining carbon deposits. Is the cylinder now leaking past the spark plug threads? If not, and the spark plug is still functioning, try to leave it alone if possible. Otherwise, I would first try using a lot of compressed air (through the injector bore) on the corresponding cylinder, along with pliers. If the spark plug is intact but the threads are damaged, you can try removing it by pulling and twisting simultaneously. Then, obtain a Helicoil repair kit and cut a new thread using compressed air. It's better to remove the entire head.

EDIT: When replacing spark plugs on a Mercedes-Benz Vito, you may be required to sign a document stating that you will be responsible for the cost of removing the cylinder head if a spark plug breaks off during removal. It seems to be normal for Mercedes-Benz.

Hi,

If everything else is still working properly and the spark plug is already broken, I would probably leave it as is, because the TDI engine will still start with three working spark plugs - most of the time, it will even start without any spark plugs. While it's partly a makeshift solution, the effort required for the alternatives isn't insignificant either.

The only question is whether the emission values can still be met, because the afterglow has a significant impact on those values.

Best regards,

Jan.

The only question is whether the emission values can still be met, because the afterglow has a significant impact on those values.


Well, who drives to the TÜV (technical inspection) with a cold engine? Regardless, the engine will be brought to operating temperature before the inspection. So, it's really a matter of conscience. I would answer with 'It doesn't matter.'

Okay, so the bulb is still inside, and you can wiggle it back and forth. The top part (the contact) is already broken off. So, I guess I'll have to take the head off. Damn!

Is the head clamped when drilling, because when using a hand drill, it doesn't drill straight, does it?

Best regards.

Do you need a torque wrench for the camshaft sprocket?
or does it go down like that?
Best regards.

Hello,

Okay, don't give up just yet. Is the candle still firmly connected to the candle holder's threads? If so, see the instructions above. If not, you might be able to grip the threaded housing with pliers and twist it out. You don't need a puller for the NW hub; a regular copper dowel or something similar will suffice.

Does the NW (presumably referring to a component) not sit on a cone?

Hello qwert1,

A little bit of self-initiative from your side would be appreciated. Please provide the German text you would like me to translate into English. I will then provide only the translation, without any explanations.