Thread: N62 misfire
View Single Post
  #3  
Old 05-06-2020, 12:14 PM
andrewwynn's Avatar
andrewwynn andrewwynn is offline
Member
 
Join Date: Jun 2015
Location: Racine, WI
Posts: 12,523
andrewwynn will become famous soon enoughandrewwynn will become famous soon enough
N62 misfire

Quote:
Originally Posted by murmansken View Post
Chains tensioners and guides was done about 30000 km ago according to the papers and reciept that followed with the car, what happen with the tensioner that can cause this sort of damage? I work as a mechanic and I can´t se how its possible that the tensioner can stretch the chain without breaking. it must be a couple och centimeters longer now than before.



Now I have to replace both timing chains guides one solenoid etc...

Tensioner will stop providing tension. At this point the chain gets loose and "whips" think of a bull whip but made out of steel and pushed by unlimited force of the momentum of a V8 engine!

Pretty bad to fail so quick: was the tensioner OEM? I've seen non OEM I sent right back because the design didn't even LOOK similar no way it would function the same. After that one example and helping rebuild several engines that had internal destruction I would never use a non OEM tensioner.

I'm not familiar with the geometry of the N62 but did the chain "derail" and jump off track of the guides to get onto the solenoid?

There is no chance the chain from N62 is 2cm longer than new. The apparent extra length comes from guides getting chewed though usually. In rare occasion that will be followed by the chain actually coming off a toothed sprocket. At this point usually very quickly chews through the chain covers, a jam and breaks the chain and some bent valves.

Oh: loss of oil pressure due to low on or pump failure will cause loss of chain tension also.
__________________
2011 E70 • N55 (me)
2012 E70 • N63 (wife)

Last edited by andrewwynn; 05-06-2020 at 12:21 PM.
Reply With Quote

Sponsored Links