A hydraulic retractable rim is a special device used to physically fold back the frame of a car. This can be extremely dangerous if abused. Therefore, it is important to follow the manufacturer’s recommendations regarding weight restrictions and use. Never operate a retractable rim without covering the chains with a blanket, always wear safety glasses. Remember that a pullback RAM is not like a push-type or push-out RAM that pushes out instead of pulling. You should also use the hydraulic pump that comes with the ram to operate the ram, as the ram is not well suited for valve replacement pumps.
What should you watch out for when using a hydraulic retraction cylinder?
Purchase a set of metal pull chains that are classified according to the weight capacity of your hydraulic piston. Any chain can be used as long as its rating matches the weight of the ram and the ram matches the fork. When using crowbars, weak crowbar chains will break. This is a dangerous mistake.
The retraction cylinder consists of two interpenetrating cylinders, with the narrower cylinder always facing your car. Attach the hook and chain to the narrow end of the piston. The shorter the chain connecting the RAM to the vehicle, the better. Hold any of the S-hooks together and reconnect them if they come loose.
How can I use a hydraulic retraction cylinder?
Hydraulic rims are almost always used for exterior frames. Wrap the drawbar hook around the part of the frame to be adjusted. You can use a piston as long as the fork fits around the metal well and doesn’t move around.
Attach the pull chain to the hook at the end of the piston head. Then connect the S-hook to the end of your second pull chain with the hook on the other end of the hydraulic retraction rim. Push both hooks together and keep them together.
Wrap the bridge chain around in a tight circle, like a thick tree. If you don’t have any construction tools, work with I-beams or wood. The pullback ram is almost always a hook or tool. The shovel can also be used on a digger, backhoe or bulldozer.
Remove the chain link from the thin side of the hydraulic cylinder. Then take your S-hook and lift it up until you have a tight chain at a joint near your frame. The fewer the vehicle joints, the less likely the chain is to break. If there are many additional chains, you can “double loop”.
Tighten the chains by adjusting the chain connection at the opposite end. Make the necessary adjustments at each end of the chain to align the piston with the two chains. Adjust the hook or adjust the angle of the anchor to move the sides of the chains to tighten the piston.
Remove the cover with the hydraulic cylinder. A small cap covers a valve in the thick part of the retractable rim. Cap removal varies depending on the piston, but is usually removed by turning the cap counterclockwise or pushing gently from the valve.
You will need to use the pump that comes with your pullback ram. You cannot use another hydraulic pump because the valve and hose do not match properly.
Connect the hydraulic pump hose to the cylinder side valve. Remove the hydraulic pump line that comes with the ram and insert the ram into the valve, or push in and turn the lever to tighten. Double check that the connection is as close as possible before proceeding. If your pump is not properly connected to the ram, you will not get enough pressure.
Insert the pump handle into the opening at the top of the pump unit. Pull the hydraulic pump at the other end of the line as far away from the chain configuration as possible without pulling the hose. Place it flat on the floor and insert the pump handle into the opening at the top of the pump. Check the RAM manual to determine if the handle needs to be locked before using the RAM.
Use eye protection to protect your eyes. Once a chain is broken, it is impossible to tell where it will end up. Wear goggles to prevent loose pieces of chain from sticking out and damaging your eyes.
Gently pump the handle to remove the frame. Lift and close the hydraulic retraction cylinder handle to compress. Do this carefully so you can keep an eye on the size of the frame as you pull it out. The pressure in the retraction cylinder puts pressure on the car hook, pushing the metal out to allow air out and relieve pressure.