As the opening of the slurry spreading season quickly approaches, now is an ideal time for farmers to take a look at their tankers. With the vast majority of slurry tankers in Ireland being of the vacuum type, we have compiled a short practical guide to help you get your tanker ready to spread. If in any doubt about any potential issue, you should consult your local mechanic or dealership.

1 Vacuum pump & gear box

The vacuum pump is the most important part of a slurry tanker that needs to be correctly maintained. At the front of the pump is a gearbox and to the rear is an oil reservoir.

Starting with the gearbox, check that there is no play in the shaft and that the seals are not leaking. Gearbox oil level should be checked, ensuring it is not dirty or milky looking. If it is low or needs to be replaced, use the recommended gear oil.

If the tanker has been out of use for some time, it is worthwhile putting the pump into its spread position and sucking in half a litre of diesel through the exhaust. Have the rear spreading valve open (nothing in the tank) while doing this. The diesel helps free and clean up vanes and the rotor inside the pump.

The pump's oil reservoir should be topped up with the correct oil.

The oil reservoir to the rear of the pump should be filled with the correct oil depending on the season (SAE 30 in summer and SAE 20 in winter).

These pumps use oil, and need to be topped up regularly. The rate of administering oil (oil dropper) to the pump varies between manufacturers. Usually, it’s from one to three drops per second. The dropper should be free-moving and easily adjustable, with a clean sight glass. A well-oiled pump is key for long working life.

2 Pressure relief valve & pressure gauge

The pressure relief valve can stick in position after sitting idle for the winter so it should be tested.

The pressure relief valve is brass-coloured and located to the top of the pump with a red pull ring. These are set at 0.5 bar. If air leaks out below this the tanker will have a poor spreading width while anything over 0.5 bar may lead to pump damage over time. When 0.5 bar pressure is reached, air should be dumped, creating a louder noise. These valves can stick after spending a winter outside, so they need to be checked.

The pressure gauge should be working and be clean for good visibility.

A properly functioning gauge should register whether the pumps in vacuum or pressure. If you are unsure if the gauge is working or not, when the pump is running and in pressure, the hand on the gauge should drop once the rear valve is opened. The gauge face should be kept clean and replaced if not working.

3 Towing eye, brakes & tyres

A typical 2,300 gallon slurry tanker will hold just under 10.5t of liquid in addition to the weight of the tanker itself. So it is very important that the towing eye and running gear is examined for any wear. If worn out, a new towing eye is relatively cheap and quite easy to fit. If the tanker has a sprung drawbar, the guide slides should be greased regularly along with the drawbar pivot.

The towing eye should be inspected for wear and replaced if necessary.

As you are dealing with big weight on public roads, it is of critical importance that every tanker has fully functional brakes. If parked up for a long time, the brakes should be checked to ensure they are not sticking.

If it is the case that the brakes need adjusting, this should be done in accordance with the manufacturer’s specifications. Meanwhile, the handbrake should be able to be operated and released without a problem.

Brake performance should be checked and slack adjusters adjusted if necessary.

More often than not the tanker’s tyres will become structurally damaged before the actual lugs are worn. A structurally damaged tyre is prone to a blowout, which could have serious consequences. Tyre pressure is also important. It should be set based on the manufacturer’s recommendations, but farmers should be aware that often large tanker tyres need to have more pressure in them than tyres on other implements. In addition, the wheel nuts should be checked regularly.

Tyres should be examined for cuts and excessive wear.

Wheel bearings need to be checked for wear or play. Ideally the wheel needs to be raised off the ground to check this. Some hubs have a grease nipple so it’s worth greasing this every so often. Wheel nuts should be regularly checked and torqued to the manufacturer’s recommendations.

4 PTO & hydraulic hoses

The PTO shaft should be removed and the sliding profiles taken apart. This will ensure they have not seized and check for any bends. The universal joints should be inspected to see if they have seized and checked for wear. Likewise, the lock pin should also be inspected for wear. It’s vital that all PTO covers and guards are fully functional and that they have check-chains to anchor it at both ends.

Universal joints on PTO shafts should be checked and greased regularly.

All hydraulic hoses and quick-release couplings should be inspected for leaks or damage and replaced if necessary. Emphasis should be placed on the hydraulic brake hose.

All lights should be intact and working.

5 Suction point & dribble bar

Starting at the gate valve, if it is not closing properly, often a small stone or debris may be stuck in its groove. If this doesn’t resolve the issue, the gate valve may need replacing. If there is any slurry leaking around the stem of the gate valve, it may be resolved by simply tightening the collar nut.

Moving on to the inlet connection, the rubber seal used to seal the suction between the pipe and the tanker should be checked for damage. The clamps should also be checked to ensure they are tight to avoid any leakage of slurry or air when filling the tanker.

Suction points should be given the once over.

Thanks to TAMS aid, dribble bars and trailing shoes have become increasingly popular in recent years. Many of today’s macerators are fitted with an integrated foreign body separator to prevent debris from blocking the outlets.

Most also contain self-sharpening and self-adjusting blades. As standard, most will have a stone trap which is located under the macerator to collect debris. This is easy to clean out and this should be done often.

The dribble bar itself should be given a once over, checking for blocked distribution pipes and outlets. All bolts should be tight and lubrication points well-greased especially on pivots.