A pivot is a simple machine that fails in predictable places. Most of a season’s downtime comes from four of them — and all four are cheaper to catch on a walk down the machine than to fix in July.

Blocked or worn sprinklers

Walk the machine once a month with the water on and look along the line. A worn nozzle throws a wider, softer pattern; a blocked one throws nothing. Either one puts a dry or a soaked stripe through the field, and neither announces itself from the pivot point.

Pressure drifting out of range

The pressure switch shuts the system down on over-pressure, but a slow drop will not trip anything. A tiring pump, a partly closed valve or a leak at a hydrant shows up first as a falling reading. Read the gauge at the pivot point every time you start.

Gearbox oil and wheel tracks

Check the gearbox level at the start of the season and after any tower has been stuck. Deep wheel ruts mean a tower is dragging — find the cause before the track becomes impassable. A worn coupling shows up as backlash long before it shows up as a stopped tower, which is the cheapest moment to replace it.

Damage to the galvanizing

Hot-dip galvanizing is what buys the machine its decades. Anywhere it has been ground, welded or scraped through, treat it before the winter rather than after.

The season checklist

1. Before the season

   Gearbox oil levels, tyre pressures, panel voltage and running hours, and a look at every point the galvanizing has been broken.

2. Monthly, with the water on

   Walk the full length and watch the pattern from every drop. Note stripes, not just failures.

3. At every start

   Pressure at the pivot point, and a glance at the voltmeter — low or unbalanced supply is what burns gearmotors.

4. After any tower sticks

   Check that gearbox, that coupling and the track it cut before running the machine again.

The parts worth having on the shelf

Browse the spare parts catalogue