The rear hatch of my 1994 124 wagon recently began falling on my head and, after reading several germane posts on this forum, I decided to replace the lifting cylinders myself.
Despite my previous readings, I found that there was a learning process involved - the first cylinder took more than 3 hours to replace, the second was done in 20 minutes - so I thought I would share the step-by-step process I found effective.
Note: these are high pressure gas cylinders and even in a faulty state, retain enough pressure to make removing and replacing the pivots difficult.
1. Remove four screws along the rear of the plastic molding at the rear of the headliner.
2. Remove 2 screws (1 each side) at the forward projections of the same part.
3. remove the screws at the top of the platic molding that covers the edge of the rear hatch and laps over the ends of the previous part.
4. remove the plastic molding by sliding it back and snaping it out from under the rubber molding around the rear side glass.
5.The headliner is attached with 2 plastic push pins on either side - remove these. The back edge of the headliner is held on 3 metal tabs that pass through the headliner and around a wire - disengage these by pulling slightly rearwards and down - the back section of the headliner will now fall free.
6.The clevis on the rear (rod end) of the cylinder is held with a pivot pin that is locked with a spring washer. I removed these spring washers by reaching in through the rear with a pair of long duck bill pliers. They can also be removed from the inside when the pin is removed (see below)
7.With the hatch propped up as far as possible (to relieve as much pressure as possible from the system) climb into the rear cargo area.
8. The forward (cylinder end)of the units is held with a square headed pin that passes through the interior sheet metal. The pin head is secured with a bent-over tab. Straighten the tab with a small pry bar and a hammer and remove the square headed pin. This will require some effort since the pin is under pressure even with the hatch at its highest point. I used the small pry bar to back it off until I could lock a pair of vise-grips on the head and pull it out.
9. Now, remaining inside, close the hatch. This will bring the rear clevis back to a point where it can be accessed through an opening in the sheet metal. Since there is no longer any pressure of the system, the pin is easily removed. (you will have to remove the locking spring at this point if you have not already done so frm the opening in the rear of the body. The clevis is surrounded by a rubber bellows that needs to be squeezed forward to access it.
10. The cylinder unit can now be removed by sliding it forward through an opening in the sheet metal. The dropped headliner allows enough clearance to pull the unit all the way out.
11. Insert the new unit through the same opening and jiggle it around until the clevis on the rod end engages the hatch arm.
12. Replace the clevis pin and spring clip.
13. Open the hatch and prop it at its highest position. This will pull the cylinder unit rearwards until the mounting hole nearly corresponds with the hole in the sheet metal. The squared headed pin has a slight chamfer on the end of the pin and can be inserted in the hole and driven home with a hammer.
14.Re-bend the locking tabs.
15.Re-fitting the headliner and the plastic trim is a reverse of the removal procedure.
I noticed a comment suggesting that it is only necessary to replace one of the two cylinders. If you find that this is the case, you have simply chosen the faulty cylinder to replace. I did both and it is clear that one cylinder is not sufficient to keep the hatch open. I replaced the first cylinder and found that the hatch would stay open. I decided to replace the second and, despite the fact that I had a new cylinder installed on one side, as soon as I released the pin on the second one, the hatch slammed shut. Fortunately, no part of me was extending out the back at the time!
Despite my previous readings, I found that there was a learning process involved - the first cylinder took more than 3 hours to replace, the second was done in 20 minutes - so I thought I would share the step-by-step process I found effective.
Note: these are high pressure gas cylinders and even in a faulty state, retain enough pressure to make removing and replacing the pivots difficult.
1. Remove four screws along the rear of the plastic molding at the rear of the headliner.
2. Remove 2 screws (1 each side) at the forward projections of the same part.
3. remove the screws at the top of the platic molding that covers the edge of the rear hatch and laps over the ends of the previous part.
4. remove the plastic molding by sliding it back and snaping it out from under the rubber molding around the rear side glass.
5.The headliner is attached with 2 plastic push pins on either side - remove these. The back edge of the headliner is held on 3 metal tabs that pass through the headliner and around a wire - disengage these by pulling slightly rearwards and down - the back section of the headliner will now fall free.
6.The clevis on the rear (rod end) of the cylinder is held with a pivot pin that is locked with a spring washer. I removed these spring washers by reaching in through the rear with a pair of long duck bill pliers. They can also be removed from the inside when the pin is removed (see below)
7.With the hatch propped up as far as possible (to relieve as much pressure as possible from the system) climb into the rear cargo area.
8. The forward (cylinder end)of the units is held with a square headed pin that passes through the interior sheet metal. The pin head is secured with a bent-over tab. Straighten the tab with a small pry bar and a hammer and remove the square headed pin. This will require some effort since the pin is under pressure even with the hatch at its highest point. I used the small pry bar to back it off until I could lock a pair of vise-grips on the head and pull it out.
9. Now, remaining inside, close the hatch. This will bring the rear clevis back to a point where it can be accessed through an opening in the sheet metal. Since there is no longer any pressure of the system, the pin is easily removed. (you will have to remove the locking spring at this point if you have not already done so frm the opening in the rear of the body. The clevis is surrounded by a rubber bellows that needs to be squeezed forward to access it.
10. The cylinder unit can now be removed by sliding it forward through an opening in the sheet metal. The dropped headliner allows enough clearance to pull the unit all the way out.
11. Insert the new unit through the same opening and jiggle it around until the clevis on the rod end engages the hatch arm.
12. Replace the clevis pin and spring clip.
13. Open the hatch and prop it at its highest position. This will pull the cylinder unit rearwards until the mounting hole nearly corresponds with the hole in the sheet metal. The squared headed pin has a slight chamfer on the end of the pin and can be inserted in the hole and driven home with a hammer.
14.Re-bend the locking tabs.
15.Re-fitting the headliner and the plastic trim is a reverse of the removal procedure.
I noticed a comment suggesting that it is only necessary to replace one of the two cylinders. If you find that this is the case, you have simply chosen the faulty cylinder to replace. I did both and it is clear that one cylinder is not sufficient to keep the hatch open. I replaced the first cylinder and found that the hatch would stay open. I decided to replace the second and, despite the fact that I had a new cylinder installed on one side, as soon as I released the pin on the second one, the hatch slammed shut. Fortunately, no part of me was extending out the back at the time!
