Oh my word, what an absolute sh*t-show of a weekend!
It started off really positively, I went out Friday evening just to get the front of the car on jack-stands, so I could crack straight on with replacing the AC fan on Saturday morning, but I ended up 'just another 5 mins' for about an hour and completed replacing the fan before I came in. I can get it booked in for an AC re-gas now.
Buoyed by that success, on Saturday morning I went about deleting the secondary air pump, and finally fitting the blanking plate
@t-tony sent me months ago. Another item ticked off the list.
I should have stopped there
But no, next thing was replacing the lower control arms. I already knew one of the ball joint boots was torn by my own doing last year when I replaced the knuckle, but checking the last MOT advisories (which is due in a few weeks), I remembered that it had advisories for play in the ball joints too, so I thought I'd replace the control arms with the ones I fitted new to my first Z3 last year, that I bought back off the guy who bought what was left of the blue one (still following me?) Anyway, I found that the ball joint covers were torn on those ones now too (again, at least one of them probably by my own doing, I'm guessing there is a knack for using a ball joint splitter without tearing the boots?)! Bugger. I have ordered another pair of arms which should come this week and carried on with removing the old ones...
Offside
Disassembled the brakes, undid the knuckle ball joint. Started undoing the chassis ball joint when the corrosion on the threads caused it to seize up and the whole ball joint was just spinning. And the hex/torx hole on the top was so corroded, I couldn't get anything into it, nor was there enough space to hammer a spline bit in anyway. However it was loose enough to split the ball joint though, so I did that and then undid the lollipop bush bracket. With that the control arm was just hanging down by the nut on the chassis ball joint, that I still couldn't undo.
I thought I was being clever by angle-grinding through the exposed ball joint stud, the arm would fall off from below, and I could lift the stud and nut out through the top, right? Nah. This is when I discovered the stud is tapered, and now I just cut away any material I could use to hold against the torque of undoing the nut. I was a bit stuck at this point. I grinded out a slot in the bottom of the stud for a flat-head screwdriver, but I couldn't go very deep before I would have been grinding into the subframe, and with the torque of trying to undo the nut, the screwdriver approach wasn't working. I thought I was going to have to find somebody who could come out and tack-weld the bottom of the stud to the subframe, but I thought I'd take a break and switch to the nearside first.
Nearside
Carbon copy of the offside, except this time I knew not to cut the control arm off!
I've had an induction heater in my Amazon basket for a few months now, so I decided now was the time to pull the trigger, and ordered one to come on Sunday. I wasn't sure this would help with my butchery on the offside, but I was optimistic it would get the nearside one off.
On Sunday morning while I waited for the Amazon delivery, I took the powerflex lollipop bush & brackets off the former-donor arms and cleaned them up, and while the front discs were off, I cleaned up and painted the disc hubs black.
I also removed the front-anti-roll bar and was going to start sanding that down and giving a fresh coat of paint, but the Amazon delivery turned up so I turned my attention to the induction heater... It's big. Too big in fact. Even with the airbox removed, it wouldn't fit down the side of the engine to reach the nut, and the wire coils that came with it were rigid, so I couldn't attempt to come at it from below either.
To my surprise, I tried the nearside nut again (via socket wrench and a number of extensions) and this time I got some movement from it. I'd like to think it was the sight of the induction heater that scared it into compliance, but really I expect it was the copious amounts of WD40 it had been bathing in for 24H that finally did it! I went back and forth a few times, applying more WD40 and wire brushing the corrosion off the threads, but I still couldn't get it past the last few threads. Eventually, through shear desperation, I put my jack under the ball joint and took some of the weight of the car onto it, and that was enough resistance on the ball joint to undo the nut. Finally that was one control arm out!
I went back to the offside, there was no ball joint to put the jack on this time, and what was left of the stud went higher into the hole than the lower face of the subframe - if that makes sense, so the jack would have just pressed on the subframe, rather than the stud. I found a nut that was small enough to fit the hole, and a piece of scrap metal to stop it just pressing into the jack pad. I couldn't put enough torque on the nut with a spanner from below, however the jack was holding the stud still, which was a start! By disconnecting the earthing strap and now the secondary air pump was removed, there was
just enough room to get a socket and extension onto it and I cracked it from above. I don't think I have ever put so much force onto that wrench, I thought I was going to break something, but I got the nut off and after I removed the jack, a quick tap on the stud with the spanner and it fell out. Second control arm out!
Christ almighty, what an ordeal!
If I ever do control arms again - and I am writing this here to remind myself more than anything - I am going to remove those two ******* nuts
before jacking the car up
)