So yeah, I installed the refurbished 4WS actuator sucessfully yesterday. The things to note are:
1. You can be 99.9% sure that the rear 4WS actuator cannot be the cause for any instability of the rear wheels, since the axle rod is firmly fixed in the unit. No outer forces from the wheels can laterally move the axle or rotate it. The only way this wouldn't be the case is if the unit was severely damaged from say a sideways impact and the innards were broken and in pieces, which would make the car undriveable at even the most trivial speeds.
2. The green washer remains that were seen on my pics, are also present in my other 4WS actuator that hasn't ever been involved in any accident as far as I know. It might be the case that due to old age, the plastic material breaks down and makes a mess inside. Anyone can check their actuator by removing the Torx screw where the locking pin goes and shines a flashlight inside. It's a small window, but you shouldn't see any dirt in there in a normal unit. If that yields inconclusive results I recommend disassembling the end cover side of the unit and that will give you a clear view.
3. The Opel Vectra B tie rod ends were UNSUITABLE in my case. I guess the taper angle really is unsuitable, since it caused noticeable instability in my car - the rear wheels fishtailed over bumps. I went to a local shop that refurbished my original Honda tie rods - new ball, seat, rubber boot, taper end etc.. It's basically brand spanking new and it cost me 30 quid so I recommend doing that instead of buying some knock off tie rod end. FYI, the tie rod end that proved unsuitable is STARK SKTE-0280033 (
https://www.autodoc.co.uk/stark/7604711)
4. When changing the 4WS actuator make sure that you turn off the car with the wheels and the steering wheel in the dead center. That will make your life a lot easier when reassembling the car and you will avoid 4WS errors.
5. When the 4WS actuator is not powered and unmounted (or tie rods removed), the unit will always return to the center/straight ahead position.
6. The 4WS actuator (electric motor, inner mechanisms) is more stressed the further it turns the wheels - it compresses the spring in the "spring holder" piece when it moves from the dead center. The further it moves, the more the spring is compressed.
7.
@indigolemon I made some updates to the guide, so I guess it would be wise to update the .pdf? Sorry, I filled some info as I went along and figured out new things. Don't know how much hassle this causes you.
So yeah, this is pretty much it for my 4WS actuator project. I hope this settles the matter
