Swivel Axle

This summer I had the passenger's king pin replaced. I knew at the time that I needed to get the driver's side done but I decided to do it myself.
So what are we talking about here...?

31 is the king pin, and 21 is the swivel axle.
A picture of the new swivel axle is in this post...

http://1977mgb.blogspot.com/2007/09/swivel-axle-set.html

My swivel axle was badly worn - here is a pic of the lowering bushing, you can see how it is no longer centered.

Replacing the king pin on its own is tricky because there are brass bushings that run up the length of it that have to reamed and rebuilt. Although a king pin set is cheaper, unless you have a reamer and some shop skills, this is a hard job. Alternatively you can buy an entire swivel axle (they are usually sold in pairs) and just replace the whole unit. This is just a bolt on exercise and is easy to do.

1. Jack up the car and remove the wheel.
2. Remove the dust cap on the end of the axle #67
3. Remove the split pin and nut #71.
4. The wheel hub #68 will slide off and make sure you have some clean newspaper to catch the bits. You'll find a notched washer, a bearing race, some shims (very thin easy to loose in the grease), a spacer, another bearing race and a collar. Put these aside. Heres a pic.

5. Remove the brake caliper assembly and support it - don't let it dangle by the brake line unless you plan on replacing them!!! I used cable ties to attach it to the shock absorber.
6. Remove the steering lever- note that if you just remove this you shouldn't have to worry about getting the car realigned. If you take apart any other part of the steering you could mess it up. It'll look like this...

7. Undo the top and bottom bolts #42 and #32.
8. Remove the swivel axle and put a new one in.
9. You'll need to put new bushings and grease seals etc at the top and bottom bolts of the swivel.
10. Reassemble and don't forget the grease the swivel axle at the three grease nipples.
11. Reassemble the hub. I could tell you how to do this, but a video is worth a thousand words, so I refer you to John Twist of University Motors on YouTube.
http://www.youtube.com/watch?v=RJYIXZtnIiw

And thats it! You just swapped out your swivel axle.

Sway bar bushings

While I had the rear end up for the lowering blocks I replaced the sway bar bushings. Here is what the old one looks like

and here is the new one in place. There is another on the other side as well. New bushings will help tighten up the ride.

Lowering the car.

I lowered the B on Saturday. Its a straightforward job really. The lowering kit contains two springs for the front, two spacers and four U bolts for the back. It cost $159 from Brittek. Here is a picture of the kit in an earlier post.
http://1977mgb.blogspot.com/2007/10/some-stuff-in-mail.html Note that the picture includes some rebound straps and a couple of sway bar bushings that I added to my order.

Starting at the back.
1. Loosen the wheel nuts.
2. Jack up the car under the rear differential and put axle stands under the front bracket that holds the leaf springs. Remove the wheels.
3. Lower the jack under the differential to take some of the tension out the springs.
4. Undo the U bolts. When you remove the nuts spring will drop down a bit.
5. Optional: Undo the nut to the suspension arm. This will allow the bottom plate to be removed.
6. If you are this far, you might as well remove the rear springs and swap them from left to right, that way if they drivers side sags a bit, you'll reduce the sag.
7. Replace the U bolts with the new ones.
8. Reassemble with the spacer block immediately above the spring, but below the upper rubber pad. Tighten the bolts to about 26lbs torque. Don't over tighten them the bolts can break.
9. Add new shorter rebound straps.

You should end up with something like this (note the shorter rebound straps).



Moving to the front (put the back down with the wheels on!)
1. Loosen wheel nuts.
2. Jack up the car and put the axle stands under the cross member.
3. Put a jack under the spring spring pan and jack it up to take the tension of the spring. Don't go too high or you'll tip the car off the jack stands.
4. Loosen the 3 bolts that hold the spring pan that sits at the bottom of the spring. Also remove the nut for the sway bar end. Removing the bolts is a bit tricky if you don't have the jack perfectly positioned. But I just tapped them out using a punch and a hammer. When the last one goes the spring will snap down a bit.
5. Lower the jack and remove the spring.
6. Reassemble and it should look like this:



Rebound Buffers.
You have to modify the rebound buffers at the rear and front because the existing ones are not going to allow enough travel vertically. You'll keep bottoming out as you fly over speed bumps.

On the rear, I just hacksawed off an inch. On the front its more involved. On this picture the buffer is number 18. The spacer is 17.

Remove the buffer (18) and the spacer (17). Cut the spacer in half with a hacksaw and reassemble it so that it is at the top of 18 not the bottom. You have to cut it because it won't align with the holes in the top of the buffer unit. The buffer may also need to be bent a little to line up with the holes in 17.

This picture shows the spacer in the upper position. Its in the top left hand corner.

Levelling a leaning car

A common problem for MGBs is that they tend to lean a little to the drivers side. Speculation abounds as to the cause of this, but it seems most likely it is a function of the car being driven by one person and the springs on the left hand side getting saggy. An alternative explanation is that the car's body contorts due to the torque being created by the engine. This seems hard to believe.

My car leans, so I wanted to fix it.
Here are the original ride height numbers (measured from center of hub to bottom of chrome strip)
Original:
FL: 15"
FR: 16"
RL: 15.5"
RR: 16"
The car has a 1" lean at the front and a 1/2" lean at the back.


I then jacked up the front end and put axle stands under the front cross member. The rear ride height numbers are:
RL: 15.5
RR: 16"
From this I deduce that I have a 1/2 inch lean in my rear springs.


I then put the car back down and jacked up the rear end and put axle stands on the front of the rear spring mounts.
The front ride height numbers are:
FL: 16.5
FR: 16
Note that I the difference from left to right is only 1/2 inch not 1 inch. It seems as though the rear lean of 1/2 inch was also being reflected in the front.
It also seems reasonable to think that the front springs also have a 1/2inch sag to the left.


So, based on earlier advice, I switched the rear springs from left to right. These are the numbers I got then...
After switching the rear springs.
FL: 15.5
FR: 16
RL: 16
RR: 16

It looks like the front lean is likely due to the front springs, as the rear sag is all but gone. At this stage, I think that I will go all out and get a lowering kit
and lower the front and the back.

Swivel Axle Set

I got the new swivel axle from the bhive.  A very nice chap by the name of Gordon helped me out and got me a rebuilt one in no time.  Here are some pictures of it.


The next job is to figure out where it all goes. Actually first I plan on doing some detailed measurements of the ride height.