>>> When placing the alternator low on the cool side of a Renesis,
   an idler
    >>> pulley is necessary to avoid interference with the crank position
    >>> sensor. If a tensioning idler pulley is used, the alternator
   can be
    >>> fixed in place without an adjusting arm.
    >>>
    >>> There is limited space to install a pulley, so a small unit is
   best. A
    >>> few units are small enough to possibly fit in the available space
    >>> (first 3 pics). Timing belt idlers are often smaller, lighter and
    >>> simpler (last pic).  Am I correct to assume that most timing belt
    >>> pulleys and their bearings are NOT designed to handle the loads
   of a
    >>> serpentine belt running the water pump and alternator?
    >>>
    >>> Scott Gettings
    >>>
    >>> Good work Scott. Thanks for all the idler pictures.
    >>>
    >>> Yes.  Best use an idler designed for the job.
    >>>
    >>> Paul Lamar ...No rotor no motor.
    >>
    >> Paul & Scott,
    >>  From this end of the engine, the rotation is CW.  The idler, as
   it was
    >> depicted,  is on the driving side of the belt.  Using a spring
   loaded
    >> idler pulley in this location could lead to some oscillatory
   behavior
    >> unless it has a built in damper.  Also, re-locating the
   alternator  to
    >> the side like this will increase the belt wrap angle on the
   water pump
    >> and thereby increase the pump bearing load substantially.  So,
   it would
    >> be important to set the belt tension at the lowest value that will
    >> prevent slippage.  Toward that objective, you would want to
   maintain the
    >> belt wrap angle on the driver pulley by moving the idler in the
    >> direction I've sketched.   Finally, using the largest diameter
   idler
    >> that will fit would minimize the rotation speed of the idler.
    >>
    >> I've seen some fiber reinforced plastic idler pulleys recently that
    >> weigh much less and are probably balanced better than the
   stamped steel
    >> pulleys.
    >>
    >> Aubrey Thompson
    >
    >
    > I'm sorry Paul, I don't have MS Paint. If, in the image, you were to
    > rotate
    > the green circle counter-clockwise so as to cover the heads of
   the three
    > bolts just right of the water pump, and up from the crank pulley, my
    > suggestion would be to locate the idler/tensioner in that
   location.  The
    > drive belt would leave the crank pulley at about the 12 o'clock
   position,
    > make a wrap around the idler maybe about 270 degrees or so (the
   outside of
    > the belt would ride on the idler pulley) and meet the water pump
   pulley at
    > the 5 o'clock position.  the water pump pulley may have 230??
   degrees or
    > so
    > of belt contact---.  If the alternator were to mount as the image
   shows,
    > the
    > belt should clear the crank position sensor.  I assume the sensor is
    > between
    > the pulley/belt and the cover.  If not, I suppose the sensor and the
    > driving
    > magnet could be moved to a more convenient location.  John Pletting
    >
    > How come nobody has MS Paint? ") One of the few useful programs
    > that come with Windows. How does one do screen captures without
    > MS Paint?
    >
    > OK lets see if I got this right using Linux xpaint.
    >
    > Looks like it will interfere John. Did I do it right?
    > --
    > Paul Lamar ...No rotor no motor.
    >


   Paul: You get a gold star next to your name for today!  JP

   Thanks JP. To recap the original problem was the belt
   going to the side mounted alt. interfered with the mag. pickup.
   First jpg. Aubrey scheme appears to work. Second jpg.


   Paul Lamar ...No rotor no motor.

How do people have windows boxes without MSPaint?  I thought it was
included.  Try looking in StarMenu->AllPrograms->Accessories->Paint.

Matt-

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