Timing belt tensioner pulley arm Part No.?

[Morpheus]

Thanks for the pdf Sir and I'm not trying to get in any arguments here and it's all very good in theory but when you look at the actual components, there's no way the rubber ring design and especially fluids can absorb all these individual high frequencies efficiently (re. Newton's 3rd law of motion), hence my more 'crude' analysis. Christ, they even walk like my Typhoon one or even come off sometimes.

 

"Tuned to one frequency" it says, confirming the inability of such a rotating mass to respond to anything but the average and largest shock loads from sudden changes in crank speed to keep the engine feeling smooth and if load transitions feel smooth, it's good for the rotating assembly but not critical for function and besides, the accessory belt and pulleys will do more to absorb load variations than the damper, which just adds more mass to the equation, as it can store more energy until release but it's a relatively slow process that effectively only happens at throttle, clutch and engine braking points.

 

The smaller movements or higher frequencies require by definition, a much less flexible damper to carry them to the outer shell or ring.

 

This averages out the flex by dragging on the crank (actually reducing power, hence lightweight alloy ones - ok, except the crank!), storing up the various load peaks then throwing the total back the other way when the macro load cycle has reduced enough to allow it to rebound. Rubber etc. just makes this rebound softer, that's all, much like Bungie jumping with elastic rather than rope.

 

A solid pulley will do the same thing if tuned correctly (again, to only one frequency) but admittedly in some others will feel like the engine is knocking, I would imagine.

 

I am of course totally ignorant in theory but I stand by what I said in practice, since my mind works in a very visceral way, much like the viscous dampers themselves. I literally feel and see things like this clearly in my mind's eye, (a scary place if I eat cheese before bedtime by the way!).

 

Speaking of which