Hydraulic Belt Tensioner Bolt

[Rovert]

So I think what I am looking for is #7 on this diagram:

http://www.realoem.com/bmw/showparts...90&hg=11&fg=18


I used to use a T50 to loosen and take the belt off but today when I was going to change the pulley my T50 didn't fit right. I believe the mechanical tensioner is a T50 and the hydraulic tensioner is an 8mm hex. Here is my hydraulic tensioner picture I took with my phone:



Here is the bolt taken out with an 8mm hammered into it to take it out safely:


Here is the bolt with the 8mm hex out of it:


Do I have to get it at the dealership or do you think I can bring it to any place for a replacement?

[alexandre]

[webster]

when i put in my Rogue pulleys it was a bitch to get that off. definitely had to use an 8mm hex, where the instructions called for a t45/t50 (can't recall 100%).

i bet if you walked into the dealership and put on your prettiest face you could get it on the house.

[Rovert]

I'll make sure to do my makeup before I leave.....

Could I search for it at a car parts place? Or is this bolt a very special one? Real OEM says it's an "M10X25"....but I fit an 8mm into it...I'm confused.

[danewilson77]

I got mine from ecs. A dealer would have bit I doubt an indy would.

HTC DNA ON TT4 BETA, WILLIAMSBURG, VA

[BCS_ZHP]

M10 is the thread size/count not the size of the hex opening. The 25 is length of bolt in mm, so about a inch long. A good hardware store should have this, the kind of hardware store with drawers & drawers of fasteners. You could also change this to a normal hex head bolt of same size, if you wanted to.

[danewilson77]

http://www.zhpmafia.com/forums/showt...ntine-Belt-Diy


E46 Serp Tensioner Bolt by Dane Wilson77, on Flickr

[Rovert]

I think I want to change it to a hex head bolt. Anyone know sizes off hand to search at Home Depot? I read this from a posting at E46fanatics:

There is no reason I can think of for why you can't use a normal, high grade hex bolt. A socket head cap screw (what you have in the pics) is basically just a bolt with a different tool used to fasten it. There is no other difference in the function of the fastener. If it was inset into a counterbored hole, then it would be a different story (which is the primary reason why these types of fasteners are used).
Considering all of the problems I have read about dealing with these things, I may just replace all of mine with normal Grade 8.8 hex head bolts.

Also, the M10 x 25 description has nothing to do with the size of the hex bit used to remove it. The M10 means it is a Metric 10mm diameter fastener. The 25 means it is 25mm long.

[ryankokesh]

I hate that stupid bolt... Definitely going to replace it with whatever you do

[danewilson77]

Bruce listed size above? ;/

HTC DNA ON TT4 BETA, WILLIAMSBURG, VA