1927 Sunbeam 20.9 restoration (3)
August 2007
This is a round up of the progress made since Spring 2003.
I was fortunate in being able to purchase a few spares that became available last year.
These included:
- a petrol tank, battery box
- additional handbrake components
- replacement trunnions for the rear suspension
- sundry brake components.
- body components (including two doors!)
The spares are shown above. Then some front wings became available. These are like the 14/40 wings which were fitted to the early 20.9hp chassis. They enable the headlamps to be at a lower level. Later on in 1928, the headlamps moved right up to above front wing height. All Sunbeam models had this modification. So it means these wings would suit a recreation of an early 20.9 Light 4 Seat Tourer! (see part 1)
So I have found some time to fit the battery box (above), which was a simple job. I even found some holes on the chassis that lined up with the mounting points! This also shows a replacement trunnion that has been cleaned and fitted. (Note the wheel on the left is a bicycle wheel - I have to share this garage with some other non-Sunbeam components).
I fitted three replacement trunnions in all. Three old ones were actually quite bent, and they would not have been possible to straighten without specialist equipment. This bending was most probably caused when the chassis had been employed as a farm trailer. The rear springs are hung outward from the chassis, so heavy loads would have eventually caused them to bend.
So now the rear axle was closer to being fixed onto the chassis! However, one more link needed to be sorted out. My father had been looking at what to do with the rear spring shackles. These are the early 20.9 type that clamp onto the axle itself. One had cracked when on the chassis, the other was little better. Then, disaster! My father's car was stolen. In the boot was a top leaf and one half off the good shackle! So things were getting desperate. I had a replacement top leaf made in Bristol for £25. My father, an ex-Rolls Royce engineer who has helped out many times before, was able to manufacture a replacement shackle from the solid, and reshell the old one (in fact made out of the two remaining 'odd' halves). The time had come to now put all these components together...
The old shackle now fitted.
The new shackle now fitted. (You can see here that the back axle looks like it's spent thirty years in a field)
Front view with chassis now fully rolling, with Peter Hopes (mechanic) checking the tolerances.
Rear view. The chassis suddenly looks rather big.
This shows detail of one of the springs. As already mentioned, Sunbeams of this era (late 1920's) have cantilever rear springs. Many cars of the time had this including Rolls Royce, Hotchkiss and Straker Squire. It was thought the ride was smoother than the more common semi-elliptic springs, as befits a make suited to the middle classes. Even the twin cam had cantilever rears.
Note that the centre of the springs have flat plate fixings instead of U bolts. The original U bolts were too rusted to re-use. The plate concept is used on other contemporary cars, for example at the centre fixing of the front springs for the Bentley 3 Litre. We decided to try this idea out on the Sunbeam. A couple of thin spacers exist each side of the inner face to ensure the plate will not bend out of shape, though the curvature of the spring at this point is not great. The original shaped aluminium plate exists on the other side of the spring next to the central shackle.
This part of the exercise is nearly over. Nuts have to be drilled, split pins inserted. But now I can start on the next phases of the restoration. And for the first time for many years, it is a proper rolling chassis again.
Here's a reminder of what it was like before:
(Picture taken around the mid 1970's).
