Adjustments How do know I chAnge position Of belt

... Sometimes it has to do with the correct measures of the belt (there are many sizes and materials), you should check that if you changed the belt.... Another possibility is that the belt is too worn, or the pulley that support the belt has to be adjusted.

The easiest way to set a timing chain or belt is to mark locations of timing gears before removal of old belt or chain. Install new belt or chain keeping gear locations the same. Tensioners shoud be adjusted with out upsetting gear locations. Gear locations can be marked with paint or scribed and etched on surface. If gear locations have been changed already, you must align cam shaft (s) position with main shaft position as far as current operation. Rotate main shaft to have cylinder # 1 piston to top of stroke. (exhaust position). Then rotate cam valves for cylinder # 1 to have exhaust valve open. Mark and maintain this position during belt or chain installation. You may still have to make minor valve adjustments after you start engine.

See diagram posted on radiator housing or download picture from internet site.

Use wrench, or hand, to pull/push slack adjuster away from old belt.
Place new belt around all pulleys except the slack adjuster
Pull slack adjuster to slack position and place belt onto it.

Mine is so easy to move that I can move it w/o any tools just with my hand.

Setting the belt tension on the 707-708-717 machines with the old rubber "Continental" belts:
1. Make sure that the hand-wheel spins freely on the main-shaft bushing stub when the release knob is loosened.
2. Assuming that you are using the original 441mm "Continental" rubber v-belts, the setting is made by means of loosening a 5mm Allen socket cap screw at the base of the step pulley support.
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NOTE: The hand-wheel, stepped pulley, and motor pulley v-grooves must be clean. This is to say, that they cannot have any particulate or threads wrapped around the grooves.
4. The pulley will be automatically pre-tensioned to a 7 o'clock position by means of a spring to maintain the stepped pulley position. By pulling the belt toward this 7 o'clock position, the pulley tension can be adjusted and then tightened by means of the fixing screw.
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5. It is important to know that both the upper and lower belt tensions can be independently adjusted so as to allow the hand-wheel to spin freely for bobbin winding without having the hand-wheel drive the machine. This is done by adjusting the step pulley support + or - radially, near the 7 o'clock position.
If the hand-wheel drives the machine with the upper belt loosened, then either the belt is too tight or the hand-wheel bushing and main-shaft stub need cleaning and lubrication.
Note: Lubrication was once the standard factory procedure with a class 68 oil, but experience dictates a dry lubrication with graphite. Silicone lubes are not recommended.
6. Do not over-tighten the 5mm Allen fixing screw as the 5mm threaded frame boss can be broken off.
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Adjusting with the original Polyurethane v-belts on models 807-801-810-817-811 machines:
1. Follow the same procedure as mentioned but allow the step pulley's positioning spring provide the belt tension. Nothing more is required here.
NOTE: Sometimes these belts and pulleys get oily thus allowing much slippage. A simple cleaning of the belts and pulleys with mineral spirits can solve this problem.
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After-market belts:
NOTE: One can find after market belts that serves to drive these machines but not without some problems as they are usually wider belts and don't fit the pulleys well. In this case some adjustment will be necessary.
SewTechnical Home

The 7447 does not have a release lever. To change the belt, you must release tension of the rollers by pushing the front roller straight back until you hear it click and lock in position to change paper. Remove old paper and replace with new paper. Make sure if new paper has directional arrows to install properly.
Now you must release the front roller to put tension on paper. To do this push the front roller from the side that has the adjustment screw. This will release the front roller and allow it to go back into position. Be careful as it pops back quickly and with some force.
Turn on sander and adjust centering of paper with adjustment screw found near the front and side of sander.

Your best option is to get the Haynes Repair Manual on your vehicle. There is no real adjustment for a cam shaft. You can change the timing of the shafts by changing the position of the timing belt but I don't recommend that if you can avoid it.

To change the belt, you must release tension of the rollers by pushing the front roller straight back until you hear it click and lock in position to change paper. Remove old paper and replace with new paper. Make sure if new paper has directional arrows to install properly.
Now you must release the front roller to put tension on paper. To do this push the front roller from the side that has the adjustment screw. This will release the front roller and allow it to go back into position. Be careful as it pops back quickly and with some force.
Turn on sander and adjust centering of paper with adjustment screw found near the front and side of sander.

The timing is electronic and non adjustable. If you change the belt and don't have it set up (positioned) exactly right , you will cause major engine damage.
Pistons will hit valves and bend them. Don't do your timing belt unless you are experienced at doing that job.

All sander will have two adjustments. The first is to release the sanding belt by retracting the position of one of the rollers. The second adjustment moves one of the rollers belt tension from side to side. The roller angular position is changed, sometime by a single knob or screw, and sometimes by two separate adjusting screws.

Hi, Consult your user manual for the instructions to install a new belt.  Follow these instructions selectively to tighten the belt tension. Here they are....  
CHANGING DRIVE BELT


  Using a phillips head screwdriver, remove the two screws
in the center of the pulley cover.
  Remove the cover.
  Raise sanding belt to the vertical sanding position.
  Next, loosen the hex head set screw. Raising the motor
pulley releases the belt tension.
  Remove the old drive belt.
  Fit the new drive belt on the drive pulley first and then on
the motor pulley.
  Test belt tension by squeezing the belt with your fingers.
  Adjust the belt tension with the hex head set screw until
there is about 1/4 in. (6 mm) of give.
  Tighten the belt tension nut securely.
Note: Excessive tightness on the drive belt may cause
increased noise and overload the motor. Excessive
looseness on the drive belt may cause the drive belt to
fail prematurely and make a severe chattering noise.
  Using a phillips head screwdriver, reinstall the pulley cover
and the two phillips head screws. Tighten securely.


Good Luck!  Middles