Thought i would post up some instructions on how to replace the speedo gear that deteriorates in the instrument cluster.
Gas soldering iron ( optional)
small flat blade
#2 phillips head
jewellers screw drivers
fine grade sand sheet
new gear which can be purchased on Ebay
Step 1) Remove the instrument cluster from the car.
Step 2) Remove the instrumnet cluster main PCB from the cluster by removing the six black phillips head screws.
Step 3) Remove the speedo from the Pcb by removing the four screws, then remove the black cover on the speedo via the four screws
Step 4)With the cover now removed you should be able to see the broken gear.
Step 5) Carefully remove the pointer needle by pulling it away from the face of the speedo, then remove the two small flat blade screws to remove the face of the speedo. Take car not to bend the needle or to slip and scatch the gauge face.
Step 6 ) Remove the four flat screws from the white gauge frame. This allows you to remove the gears and tumblers away from the motor drive.
Step 7 ) Turn the gear set to the side and inspect the gears. you can now push the pin on the white geasr through to the center of the gauge and remove the gear. Remove the 2 circlips carefully and remove the black gear and the broken gear.
Step 8) Check the frame where the mounting pins for the gears are for cracks. I f they are cracked you can use a gas soldering iron with ca cutting blade to repair the cracks.
Step 9) With some excess plastic, melt over the crack and the rear of the pin to provide some extra strength to the pin. Dont melt on the side of the gears cause, cause this could cause the geasr to stall and dont overheat and distaort the frame.
Step 10) Inspect the mounting pin for any residual sticky gear ( from the old gear) and clean it off carefully with the sand sheet. Lightly lubricate the pins with silicon spray. Dont use oil or grease as these can go hard or react with the plastic gear and cause it to deteriorate.
Step 11) Get you new gear set ready and refit them in the correct positions
Step 12) fit the circlips and turn the gears with your finger to ensure that the turn the tumblers correctly.
Step 13) Refit the tumbler frame to the main body of the speedo and check the worm drive gear on the speedo motor engages the new gear correctly.
Step 14) Refit the face of the speedo and fit the needle at the 0km position. Move the needle to 60 - 80km position and release and ensure the needle rests at 0km. If it doesnt adjust the position of the needle and retry again.
Step 15) Refit the speedo to its cover, the speedo to the pcb, the pcb to the cluster and the cluster to your car. Road test the car to check everything works ok
Here is the iron i use to do plastic welding
Good luck, i hope you find this usefull!
Edited by hendrixhc, 10 January 2010 - 07:39 PM.