1.4 TDI: Piston Damage Repair & Solutions

Hi,

My sister now owns my old Seat A2 1.4 TDI, and it was starting worse and worse. So, I took it to the .

Diesel and air filters are in good condition.
Bypass pump in good working order.
Spark plugs in good condition.
...
120,000 km - all inspections completed.
The workshop was about to give up, as the problem only occurred sporadically, but then:

The seals of the PD elements were replaced because they were completely mechanically damaged, which resulted in a loss of compression.

Okay, here's the translation:

"Now things get serious: the valve seats in the cylinder head have significant marks/wear. While new seals are installed now, no one can tell us how long they will last."

Als Lösung wurde ein Zylinderkopftausch samt neuer PD Elemente, Nockenwellen ect. angeboten. Costs €3,000.

I have absolutely no idea how something like that could happen. Even a Google search didn't turn up anything useful.
Does anyone else experience this problem, or have any insights?

Best regards, David, who has run out of ideas on this matter.

'I'm familiar with this issue. However, it doesn't seem too severe based on what I can see in the photo. Therefore, the new injectors will be fastened with two screws instead of one. I wouldn't replace the cylinder head. The O-rings on the injectors only make contact where the surface on the cylinder head is still good. Those marks are from the injector body itself. It should seal up again, don't worry.'

What I don't understand is why you want to replace the entire right away. The cylinder head alone should be enough if it really isn't sealing properly, which I don't think is the case.

Sure, here is the translation of the text from German to English:

'MFG' stands for 'Mit freundlichen Grüßen,' which translates to 'Sincerely' or 'Best regards' in English. It is a common way to end a formal letter or email.

Unfortunately, replacing the seals didn't solve the problem.
When it's cold, it takes forever to start, and when it warms up, the sound is just "blah."

If anyone has any other ideas.

Engine code: AMF.

Thank you.

EMSimASZ wrote:

(The seals of the PD elements were replaced because they were completely mechanically damaged --> the compression was lost.) The O-rings of the PDE

are only seated where the surface in the cylinder head is still good. The markings are from the base of the PDE. It will seal again, don't worry. I haven't disassembled a PDE before, but AFAIK, a copper ring is used as a "compression seal" at the very bottom of the nozzle tip, similar to what is used in VP37 engines.
The area in question is not visible in the photo. If the valve seat has grooves that are too deep, the rubber O-rings will not be able to restore compression, even if their sealing surfaces are okay.
It might be possible to grind out the grooves in the lowest sealing ring with a cylindrical tool, without causing the piston dowel pin (PDE) to become lodged too deeply in the combustion chamber afterward... ?