JimMc
Platinum Member
The pilot check also keeps the implement draft from forcing the cylinder in and out changing the top link length, such as when travelling down the road with a rotary cutter lifted and hitting bumps, bouncing the cutter.
Several commercially available links use this system. All of the companies whose manufacturer's liablity insurance companies are aware that they build link cylinders use the pilot operated check valve systems.
The biggest problem comes when the hose supplying the cylinder is damaged or is worn through and ruptures suddenly and there is no check in place, dropping the tail of the implement. Other people have broken fittings off when the hose wasn't routed properly and lifting the implement pulled the fitting. In these situations the 3 point lift system is isolated and remains lifted. Many times, the force of the implement falling pulls the rod completely out of the cylinder allowing the implement to fall all the way to the ground.
Several commercially available links use this system. All of the companies whose manufacturer's liablity insurance companies are aware that they build link cylinders use the pilot operated check valve systems.
The biggest problem comes when the hose supplying the cylinder is damaged or is worn through and ruptures suddenly and there is no check in place, dropping the tail of the implement. Other people have broken fittings off when the hose wasn't routed properly and lifting the implement pulled the fitting. In these situations the 3 point lift system is isolated and remains lifted. Many times, the force of the implement falling pulls the rod completely out of the cylinder allowing the implement to fall all the way to the ground.
