This tool is no longer offered.
Tensioning of the 944 balance belt can now be done with the 920X.
Balance Belt Tensioning with the
AWX
This tool was developed in the spring of 2004 and will
help you to accurately set the tension on the balance belt
of your 944 series Porsche.
So how does it work? Measuring belt tension is done
placing a known deflecting force somewhere along the belts
span and measure the amount of deflection. For the
AWX, the force is delivered via a small torque wrench (not
included with this tool) and a swing arm. The swing arm is
designed specifically for the 944's balance belt. The swing
arm (or moment arm) has a small pointer that is used to
measure the deflection. Finally, the tool has a
specific pivot fixture that mounts to the engine and
provides a point from which the swing arm can address the
belt. It also has a bent rod, with marks to know the
ideal setting.
Tensioning the
Balance Belt
 
  
-
Above, I am preparing to set the
tensioning the balance belt on a 944 NA. I start with
removing the upper belt cover. I then remove the
the idler located above the water pump. I separate the
balance pivot from the balance belt swing arm and mount
the pivot in place of the idler located above the water
pump. Notice how the small black sled sits above the
belt. The pivot is then rotated so that the
pivot's bent shaft is oriented straight up. This ensures
that a specific pivot point near the balance belt is in
the correct position. Orienting the bent rod can generally
be done by eye but if in doubt, fashion a makeshift
plum-bob out of a piece of string and a weight (nut,
washer etc) to verify the position. While holding it in
this position the cap screw can be tightened with a hex
key.
-
The next
few steps vary depending on the model of your 944. If
you have a model that is equipped with an auto-tensioner
(87 and later) follow the steps at the bottom of this
page marked with the heading "Engines with Auto-tensioner." If your engine does not
have the auto-tensioner, continue with the next steps,
immediately below.
  
-
With the pivot in place and
secured, I'm ready to place the swing arm.
The swing arm is placed on the pivot pin and situated so
that it's sled is on the opposite side from the pivot's
sled - one sled above and one below the belt. The
swing arm can then be rotated and deflecting pressure
placed on the belt. I set the torque wrench for 35 inch
pounds (clockwise rotation) and apply the torque. When
the wrench clicks, I read the pointer's position. If it
points to the small green slot on the bent rod, then the
belt is tensioned correctly. If it reads on either side
of the green slot, then I simply adjust the belt's
tension (if pointing to the right of the green slot, the
tension is too loose, if to the left the belt tension is
too tight). Unlike the other tools, the swing arm
provides a consistent reading each time.
-
Remove the swing arm and pivot.
Re-install the idler pulley and belt cover.
Engines with Auto-tensioner
-
The auto-tensioner will interfere with
the swing arm's sled. To alleviate this problem, the
swing arm's sled must be removed. To do this use a
fingernail or small pic to simply pry off the small
snap-ring. Then, remove the sled and attaching parts to
safe location.
 
-
In the above photo, you can see the
swing arm being placed on the pivot. Notice how the
grooved pin fits under the belt and contacts the belt
between the belt's nubs. To do this you may need to
rotate the engine's crankshaft. Do this with a ratchet
and socket (do not attempt it using the starter). When
positioned correctly the swing arm swings smoothly in an
clockwise arc with gradually increasing resistance.
Verify this and adjust the crankshaft position if
needed.
-
The swing arm can now be rotated and
deflecting pressure will placed on the belt. I set the
torque wrench for 35 inch pounds (clockwise rotation)
and apply the torque. When the wrench clicks, I read the
pointer's position. If it points to the small red slot
on the bent rod, then the belt is tensioned correctly.
If it reads on either side of the red slot, then I
simply adjust the belt's tension (if pointing to the
right of the red slot, the tension is too loose, if to
the left the belt tension is too tight). Special Note: early versions of
this tool did not have the red slot. If you will return
the tool to me, I will correct this, for more info
please see this page.
-
Remove the swing arm and pivot.
Re-install the idler pulley and belt cover.
Tensioning the Cam
Belt
The cam belt part of this tool has been
discontinued - current owners of this tool may reference this link for
instructions on the discontinued part of the tool.
Other Tools Needed
Aside from the common hand tools needed to
gain access to the balance belt; you will also need a small
torque wrench. It must be capable of 35 inch pounds (in both
directions) and probably should have a ratcheting head to
allow torquing at all angles.
Preparation
If you haven't tensioned your belts before
you might look through the general procedure for how to do
this job.
Notes:
All metal parts of this tool have an iron
oxide finish and are coated with a light oil. Even so,
precautions should be taken to keep the tool lubricated and
dry to prevent corrosion.
There are currently no instructions included
with the tool. This online information (above) will be
updated though to illustrate how to use the tool.
FAQs
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"I got
the distributor cap off but I can't seem to get it back on,
is there something I'm missing?"
The distributor cap need not
be removed for use of this tool. Re-installing the
distributor cap can be difficult because of interference
with the headlight actuator bar. If you cannot get the cap
back on using a stubby screwdriver, there is one
work-around. Remove the cam gear cover, remove the round
plastic dust shield that is designed to keep belt dust out
of the distributor rotor area. Install the cap onto the cam
gear cover (without the dust shield), and install the 2
pieces together onto the engine. This is not ideal but I
admit that I have run my cars many thousands of miles
without the dust cover. Whether you use the AWX or not,
removing the distributor provides some much needed working
space.
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"Can the
AWX be disassembled for cleaning, lubrication?"
Yes, small snap rings
(e-clips) are used to hold the parts together and there are
tiny washers on either side of all moving parts. They are
very easily lost, so beware. Of course, I can help with
replacement parts, if needed.
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"Why is
the cam belt portion of the AWX no longer available?"
This part of the tool is very difficult to make
accurately and has steadily pushed my prices higher. I get many requests
for the balance belt part of the tool but not many for the cam belt part. In the
winter of 2004, I began developing a replacement for the cam belt tool. That new
tool was first tested February of 2005
and showed so much promise that I immediately removed the
old cam belt tool from the market. A few months later the
new 920X tool was made available. Since that time the 920X has continued to
evolve and now can be used for tensioning the balance belt as well as the cam
belt.
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