timing chain tensioner snap ring

[uturn]

BMWman, I just posted my findings and then saw you had posted. I immediately pulled my new tensioner out of the box and confirmed. All my numbers are moot because they are based on the old style tensioner. I guess I'll be looking at changing out a few tensioners here in the near future. Don't forget to order a new crush washer for the tensioner.

[bmwman91]

OK, makes perfect sense. I think that the reason for the design update was related to the fact that it would "stick". Thanks for taking the time to detail all of this!

[diamonddonbmw]

Ok, I need some help here. Everyone writes about popping out the piston, but how? Earlier post mentioned having it in a vise, but how do you do it without scoring the machined sections, and with what do you pop it out? There's great pictures above of it being apart, but not how it got that way. Can someone post a picture about that? I've looked around the forum but haven't found one. I'd like to install mine this weekend.
Thanks guys/gals!!

[bmwman91]

Assuming you have a new one, to get it to extend you just need to push on it to compress it a little, and it should release. I recommend pushing down on it onto a table or something, and slowly letting up on it so it does not spring apart. It shouldn't pop all the way apart, but it can (and has in my case).

To get it all the way apart, you can wrap it in a rag and put it in a vise, and then pull hard. There is NO reason to do that though, unless you just want to look at what's inside or something. Don't lose the spring!

[diamonddonbmw]

Now if only I can loosen the 19mm cap/bolt that will allow me to access the tensioner to put my new one in!! I moved the washer fluid reservoir out of the way, used 19mm six-point socket with a pipe extension to get leverage. No success! Don't have air tools available.

[bmwman91]

Wow, it really isn't supposed to be on there that tightly. Shoot it down with some PB Blaster and let it sit for a few hours. I would be really hesitant to use an impact gun on that thing.

[diamonddonbmw]

Thanks. I'll try that. Haven't heard of it before; didn't even think of WD-40. Shame on me!
Sunday update: sprayed it Friday noon, tried to loosen it later in afternoon. Sprayed it some more. Saturday afternoon tried, resprayed. This morning continuing the process. Using 19mm combo wrench and hammer. I'll post when I'm finally successful. Looking forward to having this Done!! Engine makes some initial startup rattling noise that I'm hoping this will help.

[diamonddonbmw]

No success yet.

[diamonddonbmw]

Still working on that bolt; the bolt edges are starting to round out!! Not good :(

[bmwman91]

Wow, the previous owner must have gone really overboard!

[diamonddonbmw]

Yup. Got it changed this evening after a mechanic this morning used a larger breaker bar to get the bolt loosened. It runs much quieter!!
I found the torque info, 40nm, for the 19mm bolt on m42club.com posted back in Dec 2007.

[bmwman91]

Glad you got it off / fixed. Also good that it didn't break the timing case or anything!