The good old shear grab is often forgotten about as it is made redundant for essentially nine months of the year, not thought of until the day comes to roll back the covers and open the pit. But this is one implement that requires good maintenance to ensure reliability throughout the duration of the winter feeding season.

A shear grab that is maintained correctly will save time, effort and prolong the life of itself and even the silage. It is a simple implement, which means very little time and money are required to keep it right. Here are a few points that should be taken into consideration when checking your grab.

Brackets

From a safety point of view, one of the most important parts to inspect on the grab are the brackets. The brackets are what link the grab to the loader, meaning high levels of stress and strain would occur here, so check for cracks in welds.

Check that both the loader and the brackets are lining up correctly, ensuring the locking mechanism is fully engaged. If this is an issue and goes unnoticed, the shear grab may become disconnected from the tractor or loader while feeding, which may possibly lead to injury or cause further damage.

If brackets are broken or require attention, replacement is advised with prices starting at €150 upwards depending on the type.

However, many companies provide refurbishment services or if you have the time and are confident with a welder and angle grinder, it’s not a big job to do yourself.

Tines

Tines are an essential part of a shear grab, usually threaded and fastened to the grab with a nut or welded in some instances. It is important to ensure no tines are missing, bent or loose.

Loose tines can damage threads if not noticed in time, meaning they cannot be tightened, deeming them useless. Missing tines increase pressure on the neighbouring tines, which eventually will create a domino effect and break them too. A full set of tines is important for the management of precision-chop silage, as the short-chop length makes it harder to contain within the grab. If tines are missing, feed may end up falling around the street increasing wastage.

Loose tines can damage threads if not noticed in time.

Tines wear over time from running along the concrete, reducing their strength and shortening their length. Replacement tines can be bought for approximately €40 each, depending on the length and diameter. Tines should be checked regularly for tightness, especially shortly after replacement.

Blades

One of the most important, yet most dangerous, parts of the shear grab are the cutting blades. The blades allow the grab to do what it does best, shearing the silage from the pit. It is important to keep the blades sharp, sharpening them on a regular basis. Sharp blades reduce the load on both the grab and the loader’s hydraulics as they cut through the silage with ease. Sharp blades mean a cleaner cut of the silage, allowing for less air to come into contact with the pit face over time, reducing the chances of spoilage.

One of the most important, yet most dangerous, parts of the shear grab are the cutting blades.

When sharpening, it is advised to only use a hand file or buffing disc. Heating of the blades will remove temper, in turn weakening the blade strength and making it harder to maintain a sharp edge. The majority of grabs today have individual blade sections that can be replaced cheaply. Others coming as complete units with prices starting from €150 for a replacement.

Pins and bushings

As well as the brackets, the complete structure of the shear grab should be checked for cracks especially at joints in the metal work, focusing on hinge points. Bushings usually have grease points. Check bushings for wear and tear and replace if necessary to prevent an unwanted breakdown during the feeding season. Bushings start from €10.

Hydraulic rams

Shear grabs are opened and closed using hydraulic power. It is important to ensure that the rams receive adequate oil pressure for maximum speed. Check the ram’s seals to ensure they are not damaged or leaking. Leaking may be caused by pitted chrome on the cylinders, in time damaging seals. Oil leaks over a long period of time will drain oil from the tractor or loader, causing further problems. Replacement seal kits start from €15 and new rams start from €250 upwards.

Hydraulic fittings and pipes

The hydraulic fittings or quick attaches should be inspected for condition and wear. A worn or faulty connection will leak oil and not hold pressure, resulting in a poor-performing shear grab. Check that all hydraulic hoses are not perished showing signs of wear or wire. The sharp wire can cause cuts as well as showing a weakness in the hose. These weakened areas will eventually burst, leaking oil and creating slippery surfaces. This increases the risks of an accident happening. New fittings will set you back by approximately €15 each.

Lubrication points

Grease is the cheapest mechanic you will ever get, therefore it is vital that all grease points on the shear grab are working and not blocked or broken, allowing the grease to actually get to the place it is needed to prevent wear. This is an inexpensive fix as new grease nipples only cost a few cent but stubborn, blocked grease points may take time and effort to clear.