Tweet
Hi all,
Got a ticking engine on our B5 S4, and would like some opinions based on a video.
Was running fine at the beginning of a trackday, and when returning
in the pits it was ticking.
oil level ok, didn't go over 100°C (5w50 with mocal 19row)
no smoking
no oil cap pressure
no pressure on expansion reservoir
runs ok, maybe a bit lumpier on idle and slight misfires (but we saw that 3 coils
are actually cracked, and it was a hot trackday)
It's a clear ticking that follows the revs and doesn't change pitch on decel and acceleration of rpm. Also no difference between warm and cold engine.
- Ideas are cam chain? that would be less timed and more a random rattle?
- hydro lifter/cam worn? rattle would be too fast on idle for that?
- wrist pen? noise should change on decel and acc of rpm?
- flywheel? the noise gets a clearer brighter pitch when pressing the clutch, but my mechanic reckons that is due to the clutch switch which alters the throttle.
- rod bearing spun? You can rev it to 5k rpm easily, the tick just gets faster, but not louder, and it has been running for about an hour now like that with no change.
- con rod bent? would sound much worse on high rpm?
What do you guys reckon?
actually the ticking is louder on video than IRL, but anyway you can hear it clearly this way.
Many thanks in advance guys!
spec is S4 engine k04 hybrid 510hp, now at 130k miles
the video:
http://www.youtube.com/watch?v=LmO3y...layer_embedded
Got a ticking engine on our B5 S4, and would like some opinions based on a video.
Was running fine at the beginning of a trackday, and when returning
in the pits it was ticking.
oil level ok, didn't go over 100°C (5w50 with mocal 19row)
no smoking
no oil cap pressure
no pressure on expansion reservoir
runs ok, maybe a bit lumpier on idle and slight misfires (but we saw that 3 coils
are actually cracked, and it was a hot trackday)
It's a clear ticking that follows the revs and doesn't change pitch on decel and acceleration of rpm. Also no difference between warm and cold engine.
- Ideas are cam chain? that would be less timed and more a random rattle?
- hydro lifter/cam worn? rattle would be too fast on idle for that?
- wrist pen? noise should change on decel and acc of rpm?
- flywheel? the noise gets a clearer brighter pitch when pressing the clutch, but my mechanic reckons that is due to the clutch switch which alters the throttle.
- rod bearing spun? You can rev it to 5k rpm easily, the tick just gets faster, but not louder, and it has been running for about an hour now like that with no change.
- con rod bent? would sound much worse on high rpm?
What do you guys reckon?
actually the ticking is louder on video than IRL, but anyway you can hear it clearly this way.
Many thanks in advance guys!
spec is S4 engine k04 hybrid 510hp, now at 130k miles
the video:
http://www.youtube.com/watch?v=LmO3y...layer_embedded
Comment