850 question re bolt that holds acc belt idler pulley

Post by **JimBee** » 19 Feb 2016, 15:10

Looking at the accessory belt routing, where it runs over the top of the idler pulley (not the tensioner pulley) it's on it's return trip to the crank pulley so spinning the idler counter clockwise. This would turn the bearing counter to the thread direction of the mounting bolt. The question then is that bolt standard threaded or left-turn for tightening.

Also, does the dust cap on that pulley just pop off?

Post by **kahl** » 19 Feb 2016, 15:50

The dust cap does pop off. Bolt is lefty loosely or standard.

Post by **JimBee** » 19 Feb 2016, 19:31

Thanks. That's helpful to know since I assume it's torqued pretty tight.

Does anybody know the torque spec on that bolt?

Post by **jreed** » 20 Feb 2016, 06:03

Based on a post from '08 (below), it looks like 18 ft-lbs.

https://www.matthewsvolvosite.com/forums ... hp?t=17913
VADIS lists the following:
Tensioner Pulley: 30Nm (22 ft lbs)
Idler Pulley: 24Nm (17.75 ft lbs) (if re-using, make sure and grease the bushing in this pulley).
Auxiliary Belt Tensioner 20Nm (14.75 ft lbs) for both screws...also the same value if you remove the center screw of the tensioner to regrease the internals.