The issue with the auto tensioner is that it is a bit of a balls up design. The problem occurs when the ratchet pawl section gets seized / stuck. You need to remove the 5mm allen bolt ( easier to remove while tensioner is installed rather than fighting with it when the tensioner out) then remove the tensioner and manhandle it a bit when it is out and get the pawl section to free up. I used a small water pump pliers to tap the unit around the pawl area ( only carry a 4 pounder for a hammer ) You will see it come loose when the tensioner suddenly fully extracts to its max length. This takes a bit ( a lot ) of patience Don't worry , it wont jump apart. You then need to pry the pawl back to release it from the ratchet teeth. I managed to pry it back with my grubby fingernail. This is fairly easy. Press the plunger fully in till you see the securing hole protrude from the end of the tensioner where the small 5mm allen bolt goes in. Pin it with a thin allen key while still pushing it in otherwise it fully extracts again and you got to start over again. Reinstall the tensioner unit with a new gasket. You can cut one from valemoid paper and PLEASE DO NOT USE SILICONE SEALER!!! Rub the new gasket lightly with clean wheel bearing grease. This will soften the gasket and prevent leaks.
Once tensioner is installed pull the thin securing allen key out and the tensioner will release onto the chain tensioner shoe. Then you need to use a thin screwdriver to assist the centre pin to seat. Rotate engine a little bit by hand in direction of normal engine rotation while pressing with medium pressure on the centre pin. Get someone to assist you to start the engine all the while you apply pressure to the centre pin.( you obviously wont be trying to turn the engine by hand anymore at this point) When the engine fires you will feel the tensioner pulsate on the thin screwdriver. You should hear the engine chain go quiet at this point.
PLEASE WATCH YOUR FINGERS IN THE FAN. You can now remove the screwdriver and refit the 5mm allen bolt with engine switched off or running...depends how brave you are. Everything should now be set till next time.
The auto tensioner is a nice idea but it is still prone to regular maintenance that will still need to be done at every service to ensure its flawless operation.
