Austin Classics

This week I decided it was time to change the rear springs on our Austin 10 Colwyn Cabriolet as they were almost useless, starting to bend the opposite way. Having a spare chassis to practice on, I quickly figured out how to do the job and found it wasn't very difficult. So I set to work on the car only to discover (you guessed it) that the job was not as simple as I had hoped. The rear shackle bolt that passes through the silentbloc bush on the back of the spring would not come out no matter how hard I tried. Hitting it with a lump hammer, heating it, even giving it a blast with an air hammer it wouldn't move. So stuck with the car in bits and a damaged bolt preventing me putting it back together, I had no other option but to cut it out, not an easy task for sure!

To cut it out I had to get a saw blade between the shackle and the spring and try to saw the bolt without cutting into the shackle. It is quite a small space to attempt to get a hacksaw into and extremely awkward. So I had to resort to a reciprocating saw, 3 blades later and finally the bolt is cut through and the spring is off.

I believe all this trouble was as a result basic precautions not being taken when installing the spring and also a non standard shackle bolt being used. The moral of the story is do the job properly the first time and it will save hours at a later date. Both of our cars have been through a number of owners most have signs of a bodger at work taking short cuts that results in some awful nightmares in the long run. In the case of the shackle bolt, the Austin 10 Drivers club carry the spare bolts so there is no need to use one that isn't the right one.

I would suggest the following preventative measures when fitting a new spring.

Before putting it together.

Brush a thin coat of copper grease on the shackle bolt and inside the bushes (try not the get it on the rubber ends). This will help prevent the bolt seizing into the silent block, you won't need much as the bolt is a tight fit so just a light brushing over it. Also put some in the eyes in the shackle that the bolt goes through. Copper grease is easy to find from any motoring shop. Next put a little red rubber grease over the rubber on either end of the silent block to protect it from other lubricants that will cause the rubber to harden and become brittle, I use Castrol Red Rubber Grease for this.

When assembled.

Now that the spring is assembled put a good helping of a water resistant grease around the join between the inside of the shackle and the spring. The grease is not so much for lubrication but more to prevent water from making its way into the joint where it will cause the bolt and silentbloc to fuse together with rust. Normal lithium grease as found in motoring shops is not really suitable as it separates and is easily washed away. (Use Morris K99 or Castrol CL for example)

This will make life a whole lot simpler next time you (or somebody else) needs to take out a spring to have it reconditioned.