EDIT: DEFINITELY NOT MELTED! IGNORE ALL THE MELTING AND HOT EXHAUST STUFF
Hi all! I have a '99 156 JTD 10v 136hp.
I changed the turbo core nearly a year ago. The first turbo looked like melted and grinded, It had a lot of free play so I assumed that the fault was the free play, causing the vanes to touch the housing and destroying everything.
BUT, I opened the turbo last week to free the geometry that had stuck, and was giving overboost issues.
I was shocked when I saw how the turbo was!! Again exactly the same!
. But had no free play this time, so the oil is doing well its job. Also there was no loud whistle that typically sounds when the turbo is broken.
The vanes were blue/yellow coloured.
I kept thinking...it looked like it had melted somehow?. I thought that that happens only on petrols that run too lean? But on a diesel?
I searched for melted turbos on TDI, and this melted turbo on a forum. EXACTLY the same as mine!
But the reason for that was a heavy remap. Mine is not remapped.
I bought a complete reconstructed turbo, it looks great and seems to have new actuator.
But I'm scared to mount it and then breaking again.
Could it be a clogged cat causing high backpressure and rising the exhaust temperatures?
I removed the cat, gave a clean with a 300 BAR 5KW pressure washer in both sides, repeated few times. After the clean ,I looked to the sun through it, the light was barely visible.
The car is very slow until the turbo kicks in, at 2100rpm. EGR is blanked with a 2mm steel plate. New original BOSCH maf, new intake pipes, no black smoke. MAP is OK. Recently, due a loud ticking noise that started to appear, the camshaft and tappets were replaced.
The engine ran much quieter and softer, but the lack of power is still there..
But another thing that makes me believe its the cat, is that it usually smells like rotten eggs.
And the turbo is not heard on the exhaust, while in a friend's 156 with same engine it's heard clearly when starting the car, just a soft whistle.
Tomorrow if everything goes as intended, I'll empty the cat and see what happens.
Maybe I'll put the new turbo if it gets noticeably better.
Please, give me a hand with this! If it breaks again I'll have to eat white rice for half a year to afford for another turbo
I did a test removing the cat and running the engine. The sound was OK, the turbo sounded great for being damaged as seen on the pics