The PEX crimp rings you see can be re crimped if they were not properly crimped in the first place. If the PEX tubing is cracked or split, it needs to be replaced. If the brass elbow is cracked, it needs to be replaced. Special crimping tools are required for the type of PEX fittings you have in your trailer. You can use "Shark Bite" or "SeaTech" fittings that require no special tools. They work well for small repairs such as what you have here. Good luck!
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