B6 Passat V6 timing chain failure

[passafist]

My 06' 3.2L Passat has been at the dealer for 2 weeks while VW decide how to remedy a problem that appears to come from a loose timing chain sprocket on the driveshaft. The dealer reckons there is no valve damage - clever design they said. It might have helped that the engine was idling when it stalled.

Question - Is this engine a 'non-interference' design?

Question - Could valve timing gear somehow retard the valve stroke sufficiently to avoid interference with the pistons at low revs?

Question - THe dealer is reluctant to lift the heads off because it could introduce problems in the future (leaky gaskets?). Is that a valid argument?

[Bora Sport]

You can check for bent valves without taking the head off. An adaptor screws into the spark plug hole connected to air compressor. If the valves aren't sealing you will hear or feel air coming out either inlet or exhaust manifold.

[passafist]

Good news ....

VW finally authorised the dealer to remove the engine and inspect the timing chains. The bolt holding the sprocket that connected the crankshaft timing chain to the overhead cam chain was working loose. The keyway for the spocket became worn and the sprocket finally let go. The chain scraped against the chain cover. The dealer felt that the resulting aluminium filings could have got thru the engine in the oil

... so VW have agreed to replace the engine! A big expense for an auto worker in Germany not torquing one bolt!

It's a shame a can't set the odometer back to zero!

Very happy with the dealer!

[gpk_gti]

wow,,how many k's did you have?

[passafist]

19000 kms, 16 months since purchase new

[passafist]

McCarrolls, Hornsby. Can't fault them! They also supplied me with a pretty reasonable loaner.

These are same guys that diagnosed my boot lid opening problem (previous post).