4.80/4.00-8" Pneumatic Wheel Tire Inner Tube Replacement. Can be used on snowthrowers, wheelbarrows, lawn tractors, tillers, trailers, and more. Has a straight valve stem for convenient connecting to pumps for proper inflation and pressure levels. How to Install a Wheelbarrow Tire With Tube? Place wheelbarrow tire on a flat surface. Insert the flathead screwdriver between the tire sidewall and the rim. Push the screwdriver handle in the opposite direction, using it as a lever to pop one side of the tire off the rim. Keeping the tip of the screwdriver between the tire sidewall and the wheel rim, work around the tire in a circle until the entire sidewall is free of the rim. Sprinkle baby powder on a new inner tube and rub it on all sides. Locate the hole in the rim for the valve stem on the inner tube. Unscrew the inner tube's valve cap and set it aside. Pull up on the tire sidewall and insert the inner tube onto the rim, working it around and into the inner part of the tire. Align the valve stem with its opening in the rim and press it through the hole. Insert the tip of the flathead screwdriver between the top half of the tire and rim. Hold the screwdriver tip down and press the tire's top half onto the rim. Turn the tire and move the screwdriver around the rim until the top half is on the rim. Remove the screwdriver, place one hand on each side of the tire and press it down while turning it in a circle to fully seat the tire's top half on the rim. Press upward on the tire underneath the valve stem to move it outward from the rim. Attach an air compressor hose to the valve stem and fill the tire with air up to the maximum air pressure stated on the sidewall. Check the air in the tire with a tire gauge to obtain the correct air pressure. If it is too full, press the center pin to release air from the tire. Screw the valve cap onto the valve stem.