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Ron Stygar Carl Buckland Dale Beuning Forums Help
Date: 11 Apr 1997 06:56:37 -0400
[In part one, our hero swapped a new set of springs an shocks into the back
end Before I could upgrade the front strut assemblies, I needed to obtain the use of a spring compressor. I called rental shops in the south San Francisco Bay area. I visit rental shops. I called tool stores. All I could find were the two-big-screws-with-a-pair-of-hooks-each style of spring compressor, the type in horror stories of disemboweled mechanics. So I bought a set new for $20, about twice the one-day rental cost of an old, grungy set that had been through heaven-knows-what. (I wish had I read a different sort of horror story before I got to this stage, the one that recently appeared on the BMW digest about how a shop that was doing just the strut assembly work invented five ways to screw up the task, and repeated some of them just for good measure. There's nothing like the incompetence of so-called professionals...) Up goes the hood. I slightly loosen the three top nuts and then haul out the torque wrench, since I haven't the faintest clue about any of the torque values for the front end. It seems a dubious technique, but lacking proper information (see part 1) it's the only choice available. The top bolts register around 20 Nm, close to the 22 Nm I had used for the back. I leave one nut hand-tight so the strut won't fall out. Back comes Jack. If picking a place for the jack stands in the back was a bit of a gamble, the front is a bloody lottery ticket. I wound up using a slightly convex area in the sheet metal aft of the wheel well, one that matched the contour of the top of the jack stand. Nothing got bent, I'm glad to say. Still, if someone out there knows the proper spot, I'd very much like to know what it is. With the car up and the wheels up, I get a good look at the spindle, I think it's called. I turn the steering wheel to get better access. Somewhere I heard I'd have to remove the brake assembly (but not bleed it) to remove the strut, but looking at it I decide it's probably not necessary and leave the brakes alone. I do free the brake line and sensor cables from the attachment points on the strut. I try to loosen one of the two bottom bolts, and the strut starts riding up and down in the upper mounting holes. Oops. The top nuts go back on and I throw more muscle into it. Even the lower rear mounting bolts weren't this hard. I had read that I should use a thread locking compound during re-assembly, and this seems to be where it gets used. Once they budge, the torque wrench guess registers around 75 Nm. Steering lock the other way and the second bolt is off. There's a nut and bolt mounted crosswise higher up on the strut, and it seems to be about 40 Nm, no loctite involved. I remove the nut but leave the bolt in place before loosening the top nuts again. With the middle bolt removed, the strut is free and I start working on getting it out of there. The hub is now attached only by the ball joint on the control arm, and the hub now wants to pivot out (away from the car) and to the right (because of the weight of the brake calipers). Whereever I had read about removing the brakes warned not to let them hang by the brake line. This isn't quite hanging but seemed close enough. By using both arms and both legs I was able to lower the strut, swing the top end out, then carefully lift it out from between the brake line and the sensor cables. If the car were up on a lift, that probably wouldn't have been possible and I expect is the reason removing the calipers is recommended. A second pair of hands makes it no big deal. Of course, with the strut removed, the hub is still trying to reach degress of caster and camber, and unless the second pair of hands is willing to stand there while you play spring compressor russian roulette, you'll need to support the brakes and hub. I improvised using a bungee cord. True to form, the spring compressors come without a single scrap of paper bearing hint on how to avoid killing yourself and the neighbor's dog. Is this some kind of macho thing? Is it a plot by the automotive workers' secret society to keep business up? I mean, hammers don't come with instructions, but neither does Fischer-Price make safe little plastic spring compressors for you to learn from. So I place the screws on opposite sides of the spring, pointed in opposite directions (one end has two hooks and the other only one), with the two-hook ends nearer to the ends of the spring. I put on eye protection and gloves, say my prayers, and start tightening. And keep tightening. And I put my foot on top of the spring for leverage and tighten some more. It's a lot of work. There's the real work of compressing the spring, plus the friction in the screw that increases with the load, and then the terror that the whole thing is going to explode in your face. With as much spring as I was able to grab, the ends never pull away from the perches, but they seem loose enough to make do. I pop off the dust cap from the top. Inside is hiding a big nut. One too big for any of my sockets. Oh, well. I could have and should have figured this out in advance, but I never saw a 22mm nut mentioned anywhere, and my big crescent wrench (the usual solution for this problem) can't reach it. If the worst thing that happens in this job is having to dash to Sears at 8pm on a Friday night, I guess I'm doing OK. [to be continued...]
Date: 12 Apr 1997 11:39:18 -0400 [In previous episodes of "No Garage Blues", we saw the replacement of rear springs and shocks and the removal and disassembly of a front strut cartridge. Despite the lack of any real documentation, our protaganist has utterly failed to damage himself or his car. But wait--there's now a loaded spring on the loose, compressed and ready to kill!] Getting the compressing screws off the old spring seems harder than getting them on. Duh. Of course it is, since there was already a load on the spring that now has to be released. And now I get to do it all over again with the new spring. Squeeze squeeze screw screw sweat sweat. Time to put it all back together. New strut, old pad, new spring, old pad, old perch, old bearing, new nut. Tighten it up. Do the spring compressor unscrewing dance again. Be amazed when the upper spring perch isn't launced into low earth orbit. Unscrew the cable clip from the old unit and screw it right onto the new one. The adjusting blade for the Koni shock makes the new strut about 3/8" longer than the old one, as measured from the seat for the spring perch, so the dust cap no longer fits. I have a call in at Dinan about this issue; they're supposed to ring me back on Monday. Showing a sudden flash of minor wisdom, I enlist some help for putting the strut back in. There's a round projection on the hub that mates with a hole between the two bolt holes at the bottom of the strut. Getting that and the upper hub mount to line up requires a bit of jiggling. Loctite goes on the bottom bolts, then I tighten it all up to my estimated torque values. I try not to think about how this will fail if I've gotten something wrong. With one side completed, I'm done for the night, so I put the wheels back on, lower the car off the stands, and take all my tools upstairs. (This all necessary because I live in a condo and don't have a private garage.) The next morning, I get set up again, jack up the passenger side, and repeat the process. This time I have help during the removal, making it easier. I also discover that the anti-roll bars really do work. With only one side jacked up, the bar exerts upward force on the side I'm working on and prevents the control arm from drooping all the way. Jacking up the other side (after temporarily securing the strut again) solves the problem. One other new thing I learn is the importance of the location of the hooks on the spring compressors. I guess I got lucky the day before, since this time the spring wasn't loose enough with the hooks fully together. The hook needs to be closer (in terms of ant-crawling-along-the-spring distance) to the end of the spring. It's great fun having to go through yet another full loosening and tightening cycle. Guess I must need the exercise. Other than that, the passenger side is uneventful. I regret that I am unable to make a contribution to spring compressor horror literature, but perhaps something will break and I'll get another chance.
I've put 150 miles on my car in the past week, but most of it was normal commuting. The change in the ride was immediately apparent. Speed bumps are clearly more jarring, but I still take ones at work at a fair clip without difficulty. I'm far more conscious of minor road defects, but some of that is certainly due to paying very close attention to the new feel of the car. I haven't taken any long trips yet so I don't know if the new ride will be fatiguing. (A 3+ hour run up to Lake Tahoe last month was a breeze.) Judgement reserved, but this is the down side of lowering and stiffening and it really doesn't seem too bad. Even after I've gotten some performance miles in (first autocross school this weekend, first track school next month), I don't think I'll be able to adequately describe the effects of the changes because I'm still an uneducated driver (first autocross school this weekend, first track school next month). The majority opinion is to improve the driver first, second, and third, then play with the car after that. I'm sure that's right, but as I said at the very start, I couldn't explain to myself why I wanted to make these changes. But wanted it I did, and I indulged myself. I do promise to let y'all know how it works out in the end.
Michael Sclafani |
