Expanding on what user Rl posted on January 10, 2021 about the lack of instructions: It was helpful to read his description of how to remove the cap, but I might suggest an easier method. If you look at the new replacement cap you can see the 4 tabs hes referring to that all hold the cap in place at the same time. Rather then use 4 very small screwdrivers to get them to slightly disengage, I simply bent each one back far enough that it bent and not longer clasped. I realize this is damaging the original part, but it was already leaking and I have the new one in hand, so I didnt see the need to be gentle. I then used an small Allen wrench for leverage through the top that forms a loop and pulled straight out. There is a spring to be mindful of but its quite large and unlikely to go flying and get lost. I should mention that the replacement kit came with 2 o-rings that were not in my original cap. Not sure if it was an older design or a manufacturing mistake, but might explain why it leaks so much on that side. I didnt disassemble the other side to compare. Overall, fairly easy to rebuild. Cheers

Nice ! Love it when I get exactly what I need !

This kit was perfect for replacing the O-rings in the Newton retrofit locking fuel caps for an RV-4. My caps were leaking in flight with full tanks. There are no instructions or diagrams included, or available from ACS, to show how to disassemble the fuel cap, which is the reason for 4 stars instead of 5. Disassembly involved prying / bending the four (4) red plastic locking tabs away from the center post, (the key should be in the locked position). I used 4 small screw drivers for this. The red plastic cap then slides off and the cap can be disassembled to replace the O-rings. The red plastic cap is replaced with the new one that is included in the kit.