Farm safety: How to fit a new and safe pto shaft guard

Getting rid of an old, and in this case, farm-fabricated guard is a necessity.

As the pto spins, the nylon bush will wear and will eventually be rendered useless. This means the guard is no longer attached to the shaft itself and can move freely. Take the retaining chain out of the equation too and you end up with a dangerous spinning guard.

With the shaft split into two halves, the old cover can be removed by pushing each of the three clips on the retaining collar inwards. This should allow the guard to slide freely from the shaft, where it should be put in the bin.

While this may sound simple, guards which have been damaged or are worn can be considerably more difficult to remove. And, even with relatively intact guards, trying to push three clips inwards simultaneously with separate screw drivers, while pulling back the guard is no walk in the park.

Three clips require pushing in simultaneously. After much perseverance, we gave up with screwdrivers .

Once the old guard is removed, the pto tubes, yokes and crosses should be inspected for any damage and excessive wear. Replace if necessary.

It may be an idea to give the shaft a spring clean, either with a degreaser or a pressure washer. Be sure to reapply grease in-between the inner and outer shaft tubes, and both universal joints, forcing any water out.

With the new shaft removed from its packaging, you should find a selection of different sized nylon bearing rings and a manual.

You should measure the size of pto tube, and the bearing recess on the yoke, consulting the manual to see which size ring should be used.

With sizes figured out, the shafts should be slid all the way together, allowing the overall length of the pto tube to be measured.

To prevent damaging the guard, both pieces should be cut 75mm (3in) shorter than the pto tube itself. As it is only thin plastic, the guard can be cut easily enough with a decent hacksaw.

Place the bearing ring over the shaft and fit into the recess on the yoke.

Sliding the guard over the tube then reveals the simplicity of the Guardloc system. As the guard comes into contact with the bush, a locking handle slides through the guard and grips onto the bush, allowing the guard to spin freely from the shaft, but preventing any fore and aft movement.

By using a screwdriver or trusty penknife, the locking handle can be easily flicked and pulled out to pull back or remove the guard.

Make sure chains properly secure either end of the guard before use. These should be shortened to prevent the chain wrapping around the guard, which can lead to damage.

The red arm locks in to secure the guard and can be removed using a screwdriver.

Lifting the arm allows the guard to be pulled back, making for easier and cleaner greasing of universal joints.

As well as the Guardloc system for conventional pto shafts, other options are also available.

One firm, which also produces easy to fit guards for wide-angle ptos is BareCo, available through Spaldings. This system uses a cam-style locking mechanism, and allows the wide-angle joint to be accessed by removing two clips.

Along with being easier to use, this makes sure you can find and adequately grease each of the points spread out over the wide-angle joint.