There are several ways to tell if your tarp is tight enough. You should SEE the crank arm bow slightly, a half inch or so. You should FEEL approximately 40 to 60 pounds of pressure when placing the arm into the retainer. You will HEAR the tarp creak as it tightens under the latchplate. Where the tarp TOUCHES the end caps, there needs to be a good seal and no flapping should occur.
By making sure the proper tension is applied to your tarp and checking that it doesn't flap and flutter in the wind. It is easy to adjust the tarp tension by taking the pin out of the U-joint. There are 21 adjustments to keep your tarp tight, so a slight adjustment to the right or left should do it.
There is a small screw that goes into the side of the roll tube and through the plastic end plug to hold it in place. This is such a tiny screw that sometimes it gets overlooked during the installation process.
You will be removing the return assembly from inside the roll tube. Remove the old cord, then insert the new cord through the PVC tube and washer; secure it with a knot. Slide the assembly back into the roll tube and secure the end plug with the screw. Slide the protective cover onto the cord and slide the cord through the eyebolt. Let the tarp hang over the edge of the box to remove the slack in the cord. Just as the tube begins to lift, tie a knot in the cord at that point through the eyebolt. For more detailed information, download the installation sheet under the support tab that's entitled Front Roll Return (Bungee Cord).
It should be 11-1/2 feet for most applications; X-Wide kits are 16-1/2 feet.
Stretch rope loses its memory in colder climates; once the weather warms up, the stretch cord will regain its elasticity. If you are using the Shur-Lok® system in extreme cold, consider upgrading your Shur-Lok® return to a Shur-Return™ or cable return system. The Shur-Return™ has a lifetime warranty.
First, you might not have enough tension applied to the tarp when it is in the latched position. You should SEE the crank arm bow slightly, approximately a half inch. You should FEEL approximately 40 to 60 pounds of pressure when placing the arm into the retainer. You will HEAR the tarp creak as it tightens under the latchplate. Where the tarp TOUCHES the end caps, there needs to be a good seal and no flapping should occur. Secondly, one bow may be setting higher than the others, focusing more of the roll tube weight on that particular bow. The additional weight can cause the tarp to wear more quickly over that bow during the rolling process.
Make sure you are using some type of ridge support and that it is installed over the top of the bows. If you have fabric caps, the tarp should go over the first bow, then under the cap and attach to the box. In grain cart and farm truck applications, you need to make sure that the first bow in from the end caps is installed no more than 30 inches for optimum performance. Also, check that the length of your tarp is correct. With aluminum caps, the tarp should be three inches from each end. With galvanized caps, the tarp should be two inches from each end. Finally, with fabric caps, the tarp should have a nine-inch overlap on each end. If you have a Wil-Slip™ joint, check with customer service for proper dimensions.
When operating a Shur-Lok® without a rear return installed, the operator needs to push the roll tube while cranking the system closed. If you are doing this, then you need to check your front return to make sure that it is set properly. The knot should be secured when there is no slack in the cord and the roll tube starts to lift slightly. If this is a new install, make sure the tarp was installed square with the trailer.
Yes, but it only becomes a concern on longer trailers. In this case, Shur-Co® recommends using one of our rear roll return systems or upgrading to an electric system to ease the roll tarp operation.
It is 25% stronger than the 18-ounce fabric and worth the upgrade if you use your tarp system frequently, providing you maintain proper tension on the tarp. Running with a loose tarp is the worst thing you can do and will wear out even the 22-ounce fabric.
Determination is made by box style and application.
Fabric Caps are watertight and commonly used on end dumps, dump bodies and grain carts to absorb a wide range of box flex. These are stronger than steel or aluminum and are economical and easy to repair or replace. For end dumps and dump bodies, the fabric flap can be substituted for a better fit around rear tailgates and hinges. Fabric caps are also used in grain cart applications on oversized boxes and oddly shaped tip-ups.
Aluminum Caps are commonly used on square boxes like gravity boxes, semi grain trailers, farm trucks and some belly dumps. They come with an easy-off option to make tarp removal faster and easier. These won’t rust but don’t respond well to a large degree of box flex.
Galvanized Steel Caps are commonly used on square boxes in the same applications as the aluminum caps but are more economical. However, these may rust over long periods of time.
Stainless Steel Caps are designed for fertilizer hauling. These provide superior corrosion resistance and lasting performance, as well as a sharper appearance.
All fabric caps are made of Shur-Co’s supreme 22-ounce vinyl fabric for increased durability and better puncture resistance.
All fabric will start to fade eventually, but Shur-Co® uses Shelter-Rite® fabric by Seaman Corporation with built-in UV inhibitors to keep your tarp from fading prematurely.
First, make sure that you are running with your tarp in the closed position. Secondly, make sure that your tarp is tight enough. Too much wind flutter will pull on the pocket and stress the threads. Lastly, make sure the fixed tube was mounted low enough on the side of the trailer so the stitching isn't rubbing on the top rail. Also, check that all your bows are mounted at the same height. If the mounting height varies, it can cause excessive pulling on the fixed tube and the threads of the pocket.