See attached PDF for instructions
If the backrest of the couch will not adjust or it wont lock in position, then it is likely that the gas spring needs to be adjust-ed.
• Your couch can have a choice of two gas springs. Look at picture 1 and 2 to determine what gas spring you have. If its picture 1, stay on this page and follow the instructions. If its like picture 2, then move onto page 2.
• Picture 3 shows the bolt assembly at the bottom of the gas spring, undo the nut and bolt and support the backrest before removing the bolt. Once removed, twist the gas spring, so that the release pin at the top of the spring has a 1mm gap be-tween the pin and release lever as highlighted by the two pictures below.
• Refit the nut and bolt loosely and test the operation of the back frame. If it's working as expected, tighten the nut and bolt.
Type 2 (Picture 2)
If your couch has the type of gas spring as shown below, and the section of your couch is either not locking in position, or is locked in position, then the gas spring will need adjusting.
• The gas spring is very simple to adjust, simply turn the main black body of the gas spring either clockwise or anti clockwise to adjust the gap between the release pin on the gas spring and the release lever.
• Check the images below to check the gas spring pin gap size is close to 1mm