Higher Strength Accessory Belt Tensioner Bolt

[eacmen]

Went to do a cooling system fresh today. This was the first time under my ownership taking the accesory belt off. The tensioner pulley bolt was totally stripped.

Got the tensioner assembly off ordering a replacement.

Curious if anyone has ever opt’d to replace that soft metal bolt with one of a higher harness/ grade? Seems like these bolts strip pretty easily.

[Slideways]

BMW updated that bolt for a torx socket. The old hex one likes to strip. Other bolts on the engine that were originally hex socket are now torx socket such as the ones that mount the VANOS valve block to the VANOS unit.

[old///MFanatic]

07129905534 Yeah replace with the newer BMW one. BMW lists it as a fillister-head bolt (what we call torx)

https://www.fcpeuro.com/products/bmw-fillister-head-screw-07129905534#description

[sapote]

Went to do a cooling system fresh today. This was the first time under my ownership taking the accesory belt off. The tensioner pulley bolt was totally stripped..

Not 100% sure it is the bolt head or its threads stripped.
Assuming the head, This happened when people tried to turn the bolt too hard and with not enough support for the torx bit to be true to the bolt. Hydraulic tensioner needs times to move the oil from one chamber to the other, slowly, so just apply a steady torque and it will move, slowly, and no stripped bolt head. Not happened to me yet.