[Beisofmarko]

Hey,

Inspected friends car (n55 535i f11) today since he snapped accessory belt yesterday on highway
and after pulling damper wheel off i saw that front crankshaft seals inner part was broken and there was string laying from there, most likely part of the belt.

I've read that these can do major damage to engine if getting stuck on timing chain.

Is it possible that there is no "worst case scenario" damage even though belt partially went thru the seal because:
- I think i was able to pull the whole string out gently because it didn't "snap" but came pretty freely out through the seal (ofcourse there could be more stuff inside)
- Drained the oil and it was clean as new, no debris of anykind there.
- Checked visually top part of timing chain assembly through oil filler cap and it was clean there aswell
- Car was driven for a while after belt had been snapped (don't ask why) and it felt "normal", no sounds or anything unusual except battery discharge light.
- Tomorrow friend is coming with somekind of borescope camera thing that we can inspect oilpan and timing chain assembly better with trough oil filler cap and drain hole.

If we find nothing more inside the engine and everything looks good, is it just new crank seal, belt, oilchange and cleanup then?
Or should the oilpan / valve cover come out anyway for further inspection?

Just trying to get some ideas how to help him best as i can and what should we do.
Thanks!

[S65Hunter]

There's like a 50/50 shot of either being ok, or totally fucked.

[Rube]

Originally Posted by Beisofmarko

Hey,

Inspected friends car (n55 535i f11) today since he snapped accessory belt yesterday on highway
and after pulling damper wheel off i saw that front crankshaft seals inner part was broken and there was string laying from there, most likely part of the belt.

I've read that these can do major damage to engine if getting stuck on timing chain.

Is it possible that there is no "worst case scenario" damage even though belt partially went thru the seal because:
- I think i was able to pull the whole string out gently because it didn't "snap" but came pretty freely out through the seal (ofcourse there could be more stuff inside)
- Drained the oil and it was clean as new, no debris of anykind there.
- Checked visually top part of timing chain assembly through oil filler cap and it was clean there aswell
- Car was driven for a while after belt had been snapped (don't ask why) and it felt "normal", no sounds or anything unusual except battery discharge light.
- Tomorrow friend is coming with somekind of borescope camera thing that we can inspect oilpan and timing chain assembly better with trough oil filler cap and drain hole.

If we find nothing more inside the engine and everything looks good, is it just new crank seal, belt, oilchange and cleanup then?
Or should the oilpan / valve cover come out anyway for further inspection?

Just trying to get some ideas how to help him best as i can and what should we do.
Thanks!

Make sure to check the oil pickup screen so that belt pieces didnt get sucked into the screen

[Beisofmarko]

Originally Posted by AlpineE93

There's like a 50/50 shot of either being ok, or totally fucked.

Yeah, but since he drove it and everything seemed working normaly i hope for the best.
If totally fucked, i would guess that it would have stalled or atleast started to make some sort of noise or something.

Originally Posted by Rube

Make sure to check the oil pickup screen so that belt pieces didnt get sucked into the screen

Good point, will do!

[ctuna]

broken belt
http://www.bimmerfest.com/forums/sho....php?t=1231881
http://www.e90post.com/forums/showpo...3&postcount=23
https://www.oxwerkzperformance.com/
http://www.e90post.com/forums/showthread.php?t=1477111
https://www.e90post.com/forums/showthread.php?t=1305990

FYI

[Efthreeoh]

If people 120 years ago treated their horses like today's Americans treat their cars, there'd been a lot of dead horses back then and rampant starvation.

Lol

[Biginboca]

Originally Posted by Efthreeoh

If people 120 years ago treated their horses like today's Americans treat their cars, there'd been a lot of dead horses back then and rampant starvation.

Lol

Why starvation? Can’t they eat the dead horses lol

[e90yyc]

Dropping the oil pan is infinitely easier than replacing the engine.

[Efthreeoh]

Originally Posted by Biginboca

Why starvation? Can’t they eat the dead horses lol

Just once.