Injector Diagnosis

[spiceredwagon]

I had the misfortune of needing to remove the head due to some missing timing belt teeth.
Hoping the experts here can help me diagnose this injector problem I discovered. I think the second cylinder (burned brown in image) has been over fueling, it has the thickest soot in the exhaust port and a bad exhaust valve seal.

http://pics.tdiclub.com/showphoto.php?photo=133374&title=injector-malfunction&cat=500

The price of parts required seems to be approaching the value of the car.
The car has 373k km and the original cam looks pristine.
Advice would be appreciated.

 

[Nero Morg]

Is there pitting in the piston? If there is, change it. Definitely looks like an overfueling injector.

 

[Mongler98]

But bad timing can cause this soot too. Fix this issue first. Then worry about nozzles.

 

[jokila]

Looks like there is a crack right on the edge of the combustion bowl of the piston. It's about the 6 oclock position in the pic.

 

[Mike_04GolfTDI]

Yep, I see a crack too. There are also some other dings here and there. The piston at the top of the picture has a chunk taken out of the edge at around the 1 o'clock position.

Pistons specifically for the BEW engine are hard to find. Used is the only source I know of.

Honestly, your best and most cost effective way to fix this would be to buy a used engine and put that in, or at the very least use it for parts.

If you have a place to work and the means to do an engine swap, then that'll be the easiest way.

If you can't take the engine out, then you could remove the head, remove the oil pan, remove the pistons, and rebuild it in place.

 

[Mongler98]

With damage that bad, the connecting rods need to be removed and the main caps as well to check for damage on the crank. And also to measure the conrods. Need new pistons for those 2 at the least.
Sorry to see another tdi fall victim to a tbelt issue. So common nowadays. There is a lot of blueprinting nessasary here to make sure it's done right. Head work too. If you diy it all you should be out the door for about a grand. Maybe slightly less. Honestly if you dont have the ability of diy this properly, I would total it and move in. Part out what you can.
Keep us posted

 

[spiceredwagon]

Thanks for the advice everyone.
I never noticed the crack in the piston until I was working with the image to post it here. It was a holy sh1t moment for me $$$ climbing.

The engine is already out of the car. I decided that would be the easiest way to also deal with cleaning the intake manifold, replace the original clutch, and replace the catalyst with straight pipe. The car had been low on power for many months and I was suspect of restricted intake or catalyst. The injector and piston issue took me by surprise.

The cylinder bores still have the factory honing pattern visible. So much of the car seems too good to throw away.

 

[Mongler98]

Thanks for the advice everyone.
I never noticed the crack in the piston until I was working with the image to post it here. It was a holy sh1t moment for me $$$ climbing.
The engine is already out of the car. I decided that would be the easiest way to also deal with cleaning the intake manifold, replace the original clutch, and replace the catalyst with straight pipe. The car had been low on power for many months and I was suspect of restricted intake or catalyst. The injector and piston issue took me by surprise.
The cylinder bores still have the factory honing pattern visible. So much of the car seems too good to throw away.

I have had many engines look good, visible crosshatch and what not, but warped and or egged past its limits. You need to blueprint the block. Basically get a bore gauge and a set of calipers and start recording. YouTube jeffmobile, he does some awesome videos on blueprinting engines.
But, about 800 will get you a full engine that runs.
Imo if you have the $, build it from the ground up with a few internal mods, make a decent go build that's low key and will last you another 350k. Seeing as you already pulled the engine, seems you have enough mechanical know how to do this. Keep us posted

 

[flee]

Good quality machine work is costly and a TDI must be set up by a knowledgeable pro.
Because you already need a head, rods and pistons, a used longblock from DAP or
elsewhere will be the cheapest and probably best option for a non-modded engine.