Late winter is the most useful time you have all year to look hard at your spreader. The season is done, the machine is cold, and you still have weeks before the first Free State application window opens. Once spring arrives and the yards need moving, there is no time to pull bearings or chase hydraulic weeps. The work has to happen now.
This is a practical walk-through for commercial trailed spreaders after a hard season, ordered so you can start at one end of the machine and finish at the other without backtracking.
Start With What Fails Most Quietly
Bearings do not announce themselves until they seize. After a season of wet, abrasive manure working past seals, the ones on the auger shafts and expeller spindle are the first to check. Spin each shaft by hand. Any roughness, any grind you can feel through the housing, means the bearing is running on its last season. Replace it now at workshop cost, or replace it in a paddock in Mpumalanga when the replacement takes three hours and delays half a day’s work.
Grease nipples are worth attention too. If a nipple accepts grease without resistance but the bearing still feels dry, the seal is gone and the cavity is packing with mud. A grease gun that moves freely is not confirmation the bearing is lubricated.
Expeller Hammers and Spread Quality
Worn hammers are the single most common reason spread patterns deteriorate without anyone quite knowing why. The machine keeps throwing material, just not evenly. On the LEO 20 Series side discharge spreader, the replaceable discharge hammers carry a 56 cm (22 in) swing diameter, and they use oil-impregnated bushings to extend service life. But no bushing survives indefinitely against pen-packed material. Pull each hammer and measure it against a new one if you have one to hand. If the profile is visibly rounded or the weight balance is off, the spread quality is already compromised.
The relationship between hammer geometry and spread evenness matters more than most operators realise, especially when loading rates go up in the early spring rush.
Check the expeller housing itself for cracks, particularly around the mounting flanges. A hairline crack that sits dry through winter opens under vibration once the machine is running loaded.
Floor Chain: Tension, Stretch, and Link Condition
Chain stretch is cumulative and invisible until a link pops or the chain skips a sprocket tooth. After a full season, measure the chain against its original pitch if you have the spec, or count the links across a set distance and compare against your records from last year. A chain that has stretched beyond the adjustment range of the tensioners is overdue.
On rear discharge machines, Grade 80 mining chain is specified precisely because manure spreading creates fatigue loading, not just tensile loading. A chain running slightly slack will shock-load every link on the pulling side each time the floor jerks forward under a clump of wet material. If you run a machine that carries lighter-spec chain, be honest about what condition it is in before the first heavy load goes in.
Look at the sprocket teeth too. Chain wear and sprocket wear happen together. Fitting new chain to worn sprockets is money wasted. The new chain matches the pitch of the old wear profile for about a season, then starts skipping.
What Wet Winter Storage Does to the Machine
Here is what actually goes wrong when pen-packed manure sits wet in a hopper through the cold months. Moisture and ammonia work on painted steel continuously, regardless of temperature. Any nick in a paint surface from the previous season is a corrosion start point. By the time spring arrives, the pitting under that nick may be several millimetres deep.
On floor boards and side walls, the critical failure point is not the visible surface but the back face and the welds. Moisture that gets behind a floor board and cannot escape sits there all winter. Check the underside of every floor board, especially the ones nearest the rear discharge. Flex them gently. A floor board that gives under hand pressure is corroded through.
The hydraulic ram seals on the tailgate or apron deserve specific attention. Cold temperature compresses the seals, but once the machine warms up in use, a seal that was borderline will weep. A hydraulic leak at the tailgate ram will contaminate the lower chain run with oil and attract more grit. Fix it while the machine is in the shed, not after the first load.
A Practical Order of Work
There is a logical sequence that minimises redundant effort. Doing it in the wrong order means cleaning the machine twice, or noticing a structural problem after you have already fitted new chain.
- Pressure-wash the entire machine, underside included, and let it dry overnight before inspection. Wet steel hides cracks and wear marks.
- Inspect the hopper floor and walls for corrosion, cracks, and weld failures before touching anything mechanical.
- Check and replace floor boards if needed. Refitting chain over a bad floor board is pointless.
- Inspect the chain, measure for stretch, and check sprocket condition. Decide whether you are tensioning, replacing, or doing both.
- Pull and check all bearings on auger shafts and the expeller spindle.
- Inspect and replace expeller hammers and check the expeller housing for cracks.
- Check all hydraulic lines for weeping fittings, cracked hose, and ram seal condition. Look specifically at any hose that runs close to the floor chain, where abrasion damage is most common.
- Check the drawbar and hitch for cracks, particularly around the welds at the hitch eye. Loaded trailing spreaders put significant cyclic stress into that joint.
- Grease every nipple with the machine in its working position, so the grease reaches the loaded side of each bearing race.
- Run the machine empty for ten minutes, then stop and check chain tension again. The chain will have seated and will need re-adjusting.
That last step catches more problems than any single inspection point. A bearing that felt acceptable by hand will make itself known under load. A hydraulic seal that was dry on the bench will show a weep once the system is at working pressure.
The KwaZulu-Natal Timing Problem
Operators in KwaZulu-Natal face a compressed window. Spring applications can start earlier there than in the higher-altitude Free State yards, but the wet-season onset also arrives faster. Missing the optimal early-spring application window by two weeks because the machine needed repairs costs real yield potential in the first flush of growth.
If you are running multiple machines and need to triage, prioritise the machine that ran the most hours last season and the one that spent the most time loaded with wet material. Both will have aged faster than their hour meters suggest.
Before You Order Parts
Replacement hammers, chain, and floor boards are lead-time items. Dealers who service commercial spreader lines in South Africa do not always carry deep parts stock through winter because demand is low. Order before the rush, not when you are a week out from your first spread date.
LEO Agriculture’s 20 Series machines use standardised, replaceable hammer assemblies on the expeller, and the 20 Series specification is worth keeping on file when you are talking to a parts supplier, so you are ordering to the correct swing diameter and bushing type rather than guessing.
For anyone evaluating whether to repair an ageing machine or replace it ahead of the spring season, the commercial spreader range available in South Africa has expanded considerably in recent years. Sometimes the repair bill tells you more than the machine’s age does.
The machine that gets properly serviced in August goes into September ready to work at full capacity. That is the only outcome worth chasing.
