Perfect Parts: Leaf Springs and Drum Brakes

Writing and Photos: James Ball

We knew leaf springs were an old design (perhaps Victorian) and after a bit of digging we found out they actually date back to medieval times – the original leaf springs were developed for carts or carriages and are one of the oldest types of spring ever designed.

Of course, the modern leaf spring is a much more robust unit, but the principle remains the same. Although not offering the comfort of the conventional coil and damper set up you see on most cars, the leaf springs do provide a solid handling and give a characterful ride reminiscent of 1960s motoring.

We love the raw, mechanical nature of a traditional Mog, and it doesn’t get more traditional and mechanical than the rear axle of a Morgan. We caught up with Brett Burbeck as he fitted the leaf springs and drum brakes of a 4/4.

We have to start off this piece with a special mention to the purpose-built trolley! It’s a simple design that’s been part of the Morgan factory furniture for decades. The axle sits on top and all the required nuts and bolts live on the shelving below.

Nearby, drip-drying above a tray of oil, were two leaf springs ready to be fitted. “We didn’t use to soak them in oil,” Brett explains, “but there were some comments about squeaking, so we started soaking them – seems to have solved the issue!”

Brett set about securing the springs on the axle with solid brackets. Large bolts are threaded through and secured. “We have to remove the ends of these before fitting to the chassis,” Brett explains. “It’s just so they don’t clash with the rest of the bodywork.”

Out came the angle grinder and the sparks fly – the smell of oil and burning metal reminded us how much we love the Morgan factory. The bolts were then trimmed down to spec for fitting. Brett then starts assembling the drum brakes.

As a traditional Morgan is so light, and sports disc brakes on the front, the humble drum brakes do the trick on the rear. Brett stuck the drums on and gave them a quick tap with a hammer to make sure they were aligned.

Next the hubs were placed on. Brett then inserted a castle nut – a nut shaped like a castle’s turret. The castle nut’s many depressions means Brett can tighten it, aligning one of the depressions with a hole in the hub which a pin is then dropped through to stop the nut from moving.

Once the hubs are on, with leaf springs attached, the whole unit is craned over to the chassis. The unit is lowed onto the chassis, Brett making sure the leaf springs slot into their appropriate joints on the chassis structure. “That’s a wrap,” Brett states, with assembly completion only taking around 30 minutes.

The rear is then ready to be fully attached to the chassis ready for some shiny wire wheels and the rest of the bodywork.