Workshop Basics

How to service your oftenneglected steering idler.

Aright-hand drive car with a steering box turns the right-hand wheel through a trackrod connected to the box’s drop-arm. The steering motion is transferred to the left wheel via a relay rod. The relay rod runs across the car and moves a second drop-arm on the left chassis rail.

Another trackrod runs from this drop-arm to that wheel. The left-hand drop-arm is connected to what, in effect, is a dummy steering box called an idler. The idler’s job is simply to follow precisely the action of the steering box, ensuring that the left wheel moves in perfect harmony with the right. A well-sorted idler can make the difference between a heavy, slow and clumsy steering action and a light, sporty and precise one.

The idler is often neglected or misunderstood. It can wear, leading to play in the steering. Far more commonly, though, its simply needs a little love and attention. It runs out of lubricant, rusts up or has its adjusting nut vastly overtightened by a hapless tinkerer seeking to eliminate play (which almost invariably stems from elsewhere in the system). This causes it to become stiff, making the steering heavy and removing its self-centring action.

Fortunately, it’s easy to put your idler right and restore dainty steering to your classic. It’s likely that all it’ll need is taking apart, looking at, cleaning, lubricating, reassembling and adjusting.

If you find worn or corroded parts, rebuilding it is generally straightforward. It’s good idea to service and adjust your steering box at the same time (Practical Classics June 2017) as well as removing all the steering balljoints to check them for play or seizure.