Wednesday, July 5, 2017

MGB - Front Suspension Refresh (Part 4)


This post finishes up the front end rebuild I started in Parts 1 (See MGB - Front Suspension Refresh Part 1), 2 (See MGB - Front Suspension Refresh Part 2) and 3 (See MGB - Front Suspension Refresh Part 3). At this point, the front beam is back in the car. The front shocks (and upper control arms) and lower control arms are installed with the spring pans. Today we will get the springs in, the swivels mounted and the front sway bar attached to the lower arms. By the end, the car could go back on the ground. The how-to for the springs I lightly touch on because it is pretty well documented around the internet. Not so much with the sway bar, so that's a little long.

Spring Thing
Back in Part 1, I described the concerns about how the springs were under load when the lower control arm was to be removed and that some level of care was needed to prevent it from launching across the garage. That concern returns as we approach the install. I followed the exact same routine: zip-tie the upper end of the spring to the top of the beam. Getting the zip-ties in the right spot may take a few tries with the jack (during the Jack Be Nimble step), but for now, just get the spring all the way up in the beam pocket and zip tie them so they are mostly in the right spot. Once the springs are suspended from the beam, we move on to the swivels. I did one side at a time, but I don't think there's a compelling reason to other than I confuse easily.

Swivels, bottom mount
The swivels are really nicely balanced lumps of steel, when they are mounted to the suspension. When you are holding them in your hands, or trying to attach them, however, they feel unwieldy. So, to protect yourself from, uh, yourself, put something soft under the end of the beam to catch the swivel when it inevitably topples over. It will topple. Since I had a bunch of things shipped, I took a larger flat box and filled it with the crumpled newspaper and air-filled bags that arrived with the parts. I highly recommend it. The alternative is a damaged swivel. Anyway, take the swivel for the side you're working on (caliper is on the rear), and fit the lower mount into the lower control arm. Thread the bolt from the kit from the front to the rear, minding the order of the washers (nut - washer - rear arm/bushing - swivel - front arm/bushing - washer - bolt head). Once you thread the castle nut on, you may feel driven to crank it on tight. Don't do that yet. Get is on pretty well, though; finger tight.

Jack Be Nimble
With the swivel attached at the bottom, it will want to fall over, especially when you start lifting the lower control arm with your jack. To prevent that, I looped a stretch of bailing wire around the top of the swivel and then around the shock absorber. This loosely held it upright, but didn't restrict movement. Now the fun part begins. Lift the lower control arm under the spring and set the inner edge of the spring inside the spring cup. Now, set your jack as we did in Part 1, on the outer edge of the underside of the spring cup. Slowly start raising the jack. I did it in spurts and then wiggled or rubber-mallet'd the bottom of the spring so it would shift in the spring cup. My thinking was that the cup was rotating 90* so the spring would be under weird tension as is was set into place, putting more pressure on the inner edge than the outer edge of the spring. I don't think it did much other than create more danger of the spring flying out, so consider that optional.

As I got closer to fully-installed, I found that the spring tension was greater than the weight of the car. I mean that the car started lifting off the jackstand before the top of the swivel was within an inch of the holes lining up. If you have a friend, not even a very heavy friend, have him or her sit on the wing over the wheel well. I was flying solo, so I stacked tires on the wing instead. Yes, that actually worked.

Swivels, top mount
As I alluded to in Jack Be Nimble, most of the top mount work is getting the jack positioned right, and raising the swivel while keeping the car solid on the stands. Once the holes in the upper control arm / shock absorber align with the hole in the top of the swivel, it's easy. I found that getting the top of the swivel to sit in the arms wasn't simple though. I needed to loosen the bolts that hold the top arms together a little bit so the swivel top could fit. You may need to do that same, just don't forget to torque them back down when you're firming up all of your fasteners.

Now do that again for the other side. I found that the first one took at least twice as long as the second side. Ironically, I had more spring slippage on the second side, but that didn't slow me down as much of the fear of that happening on the first side slowed me. Interesting.

Anti-Sway Bar
With the rest of the suspension put together, all that's left is the front (anti-) sway bar. In my searches around the internet, all of the articles I found about replacing the sway bar had the classic "install is the reverse". That is not helpful, so I'm documenting what I did that worked. If you're using your original bar, clean it up and paint where it's been chipped when you're doing your other parts. It is so much nicer, and the bushings go on much easier. We start with those bushings. The graphite-poly bushings are a solid trapezoid, so you will need to cut along the seam so it will wrap around the arm. I tried sliding it on from either end, including removing an arm-end, but that doesn't work. You have to cut it parallel to the path the arm would take through it.

Get the bushing onto the bar. This can be hard, but with some window cleaner (or plain water) as a lubricant, and a little force, it pops on. Use the little locks on the bar as a guide for where they should be located (just to the outside of the lock/clamp). Now test fit the bar with the new brackets. For the MG, there are 2 small black pieces of steel that hold an air deflector that need to fit between the bracket and the frame. Just test fit that it will roughly fit and that the bar is pointing the right way (ends pointing rearward).

With the brackets now removed you're ready to start the install for real. Hold the bar in the rough spot where it was during the test fit and wiggle one end of the bar into the lower control arm. Since nothing is preventing complete movement, this should be relatively easy. If the sway bar end is not making it through the hole no matter what you do, you could be experiencing a manufacturing defect in the arm. I had this happen: the rearward hole was too small for the sway rm end to pass through. I had to widen it with a drill.

Once the first one is through both holes so a bunch of threading can be seen/felt on the rear side of the control arm, switch to the other side. You may need to work kind of hard to get the second side in. I did. Lots of pulling and pushing before the bolt passed through both holes. Set the ends all the way in with a couple of whacks with a hammer. Place on the lack-washer and the 3/4" nut, but don't tighten it all the way down. Now shift to the brackets, the metal thing, and the bushings. Thread in the 2 pairs of 1/2" bolts, but again, don't tighten. Now, push/pull on the bar left and right to makes sure it is centered and there isn't any torque holding it out of center. Now, tighten the bolts and nuts down. Again, I recommend new fasteners.

Now, we can lower the car. I set the jack under the rear edge of the front beam, lift the car just enough to get the stands out and set the car down. After so many months of the front being in the air, it really looks kind of weird. Really low. For fun, I jumped up and down on the front bumper. Where there used to be considerable bouncing both on the initial jump, but in aftershocks as well... the MG barely responded to my jump and didn't bounce. It just returned to it's ride height. So tight. Once I get back on the road, it is going to hold the road like a brand new (or better) MGB.

That's it for today. This has been an incredible marathon, but feeling the difference bouncing on the front bumper tells what it will be worth. The front end should be in solid operating shape for another 40 years. Thanks, as always, for following along. I will get the festival review, the bus improvements, another road story, etc. posted as I can get to finishing the stories.

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