Cant believe this caused engine to lock with no damage !

[SNAP-ON]

Been a vehicle technician for 23yrs now and own an altea 2.0tdi sport myself . Just had an 05 2.0tdi sport dsg towed in with locked/seized engine . Turn key and nothing just locked up , removed timing cover to check for snapped belt but perfect so thought maybe gearbox as turning crankshaft with spanner the engine would turn anti-clockwise only . Turning engine clockwise just locked up !

Can you guess what happened or caused it as i couldnt believe it myself ?

 

[andycupra]

and the odds of us guessing i assume are massive...

something silly like an engine part fitted backwards?
a spanner in the engine?

 

[murph81]

DMF, starter motor?

 

[SNAP-ON]

Bloody alternator pulley lol !!!! Removed the fanbelt to see if it would start and it fired up on the button . How the hell this did not strip or snap cambelt is beyond me as car was travelling at 30mph

 

[CrispDust]

Suspect alot of the Alteas/ 2.0 BKD engines are getting to the point where the pulley fails (another poor VAG design) I had to replace mine about 3-4 months ago. At least it is a seperate part and not integral with alterntor!

 

[murph81]

MY BWJ TFSI engine has one as well, its not just the TDI's.

 

[Chambers_CUPRA]

Most alternators now run clutch pulleys. Even the French are in on it.

 

[pdh 14a]

Driven into deep water?

 

[Nath.]

So, what is it, a one way bearing (torrington clutch)?

 

[CrispDust]

Yeah, it slips in reverse to reduce belt "flap", such occurs in throttle lift off.

 

[Nath.]

Does a CR170 have this? I will keep my eye on it if so.

 

[CrispDust]

Yep. They start to either loose the freewheel, which puts strain on belt/tensioner or seize up, which then snaps belt/tensioner

 

[James_R]

Seen this happen a fair few times, we had 2 tourans in on the same week both with this issue, one a 2.0BKD, the other a 1.9BKC

It's a very strange occurrence and it shows just how much force is held by that one component.

Most modern vehicles use free-wheeling pulleys, they started to use said technology around 12 years ago. Lots of VAG, Renault and Mercedes's cars have them fitted.

 

[James_R]

I've also seen them cause the alternator bearings to fail and seen them fall to pieces leaving just a metallic nub on the end of the alternator.