Tuesday, 2 March 2021

Steering Rack Rebuild

The steering rack was in good condition. It was just really dirty!

So it was the usual process of stripping it all down and preparing for paint, then putting it back together with some new parts.

These definitely needed replacing!

But the whole main part was generally in very good condition and came up well using the wire wheel brush.

The main issue was the parts that were missing. Like washers, gaiters, grease nipples and clips. But once ordered they all fitted perfectly.

Below are the new shims that help the column fit into the brackets securely.

Here is the steering column all in place! All that is left to do is inject the grease.

The Rebuild Begins

Over the last couple of months I have been preparing the chassis to start installing the steering and suspension. In order to do that I needed to paint parts of the engine bay.

I bought a few rattle cans of old english white paint and started to prepare the engine bay which involved sanding down the primer to provide a key for the new paint to stick to. I used 200 grit sandpaper and gave it a good once over. Then hoovered up all the dust as best I could. Then using a specialist paint cleaning solvent and lint free cloths I sprayed and wiped down all surfaces and allowed to dry. 

Once the first coat was applied I needed to repeat the process with even finer sandpaper. Starting with 800 and then 1000 grit for the final 3rd coat. The finish was really good for my first attempt and considering it was just the engine bay I'm very happy.

The first item I wanted to install was the steering column which I had recently finished restoring with the new parts.

It went in so well having cleaned up all the parts so next up was the front shocks or dampers.

Starting to come together! Next up will be the front suspension.

Front and Rear Shock Absorber Rebuild

 When I removed the rear shock absorbers I thought that they were quite badly corroded. 

Once I had removed all of the underseal and dirty off much of the out metal surface was corroded, but not so bad that I thought would affect the structural integrity or performance.

You can see how the metal has become all pitted and rough. 

Even so, I hoped that these would be restorable, so I purchased some shock oil and some new gaskets and started to work.

There are two chambers that holds the oil. One is accessed by removing the 6 screws. 

The gasket was nearly completely perished and the inside was near black with grime. What oil that was in there resembled metallic grey paint with glitter in it. This is not a good sign. 

With some light cleaning it started to look a lot better. Using the new oil I flushed it out a few times to try and remove as much of the grime as I could.

Once I had cleaned this up as best I could it was time to refill the chamber with new oil.

This now looks much better. The oil needs to be filled up to the lowest point of the drain plug bolt which is shown in the top left of this picture. I slightly overfilled mine and then removed the bolt afterwards to set the level.

Before fitting the gasket it is important to clean the surfaces as best as you can. I used fine wet and dry paper.

Once in place you can then refit the lid. As with all gaskets you should tighten the screws from the inside out.

The next chamber is accessed by the lower value bolt.

It isn't easy to see but the colour of the oil was similar to that of the above. 

Here's what I got out of all the shocks and you can see how dirty the oil was. Definitely needed doing.

Once the value bolt has been removed there are these components although it turned out that there was a washer missing from one of the shocks which sits between the spring and value.

Once you have drained and flushed the old oil you can refill the chamber. If you start with the arm in the lowest position and start to fill the oil until the chamber is 3/4 fill, then slightly raise the arm and this will push the oil further into the chamber and the level will fall allowing you to put more oil in. Keep repeating this process until you the level remains the same.
You then have to make sure you get all the bubbles out of the chamber. Keeps slowly moving the arm up and down to work out the air bubbles.

When you are happy that you have all the bubbles out you can slowly replace the bolt. It is normal to have an overflow of oil. 

Now hopefully you'll find that when moving the arms you should have a constant and stiff resistance throughout the full range. Unfortunately for me one of my shocks started to develop an issue. When moving the arm I could feel a judder at one point. I rechecked the levels and tried again. The juddering got worse and then the the resistance dropped away and became inconsistent.  

This is because the inner piston that has rubber seals have failed, which for me means I need new shocks. I felt I should replace both of them as they are the same age and condition, so the chance of the other failing is quite high. 

The front shocks follow the same process so here are some photos to show you how that went. Both of my front shocks were in a much better condition than the rears and have come up very well.

Very dirty old oil

Here is the highest oil level point. 

Monday, 1 March 2021

Rear Brakes Rebuild

With new parts delivered I could start rebuilding the rear brakes.

I mentioned before that the rear bearings are in good condition so I won't be replacing them. Before I could rebuild the brakes I needed to put the rear axle and hub back on with new oil seals and gaskets.

Both surfaces of the hub needed a good clean. I used fine wet and dry paper to remove all the old crud.

As part of the preparation I had removed as much of the surface rust from the back plate and then applied a couple of coats of rust converter and then a couple of top coats of black chassis paint. It was now ready to start to install the new parts.

First up was the oil seal and gasket. I made sure the groove was very clean and then put a small amount of oil in the groove to help settle the seal.

Gasket goes on easily.

Then carefully slide the half shaft in the differential and then on to the inner hub mounting bolts. If you have wire wheels like me make sure that you put the correct hub and half shaft in the right end of the axle. Then make sure the screw hole is aligned and then tighten the screw.

Once that is in place I moved on to the wheel cylinder that contains the two pistons that force the brake pads on to the drum. I should point out that I did paint the pistons before putting them back into the cylinder to stop them rusting as they did before.

In order to keep the cylinder in place you have two options. Could can either use a washer and circlip or you can use a clip as I have used. This is partly because a new washer is not currently available from Moss and it needs to be exactly the right width. The clip I used is slightly bent to ensure everything is tight and stops the cylinder moving around.

I have seen some people use a tools to get this clip on but a screwdriver and a little bit of pressure and it clips on well, even if it did scratch the paint, which I tidied up afterwards.

Next up is to put the handbrake arm and new seal in place. Quite easy to do.

Then the pads themselves. This is a fiddley job!

I have to admit that I had two goes at this and it took me a while to try to understand why on one side the pads were reasonably tight and in place and on the other the pads were flopping around all over the place.

It turned out that although the springs looked ok, one wasn't even the right spring and was longer which caused the looseness, but also over time springs lose their strength, so I bought a new set from MGB Hive

I still cannot believe that someone had fitted the old pads with this top spring. The braking must have been all over the place.

The best way to show how to correctly fit the pads is to use this diagram:

When I fitted the pads I put the top spring in place first and then slid the pads over the hub and slotted the handbrake arm into the slots as shown below and then set the top of the pads into the cylinder pistons.

You need to make sure you clip the spring around the handbrake arm, which helps to stops vibrations and the brakes squeaking.

The bottom spring is tricky to get on. Although the photos show the pads in place, I actually fitted the bottom spring with the bottom of the pads off the adjuster just behind the hub. This allowed the pads to be closer together and the spring was easier to clip into place. Then you pull the pads back into their slots on the adjuster.

Once that has all been checked and making sure it is all tight you can fit the drums on. 

If like me there is some rubbing when first fitting, you should check the adjuster to make sure it isn't over tightened. But some initial rubbing is normal until you get a chance to drive the car to test the brakes. They should settle in with a few miles. If not you need to check the installation again.