Put the Loquat pieces into a large pot, and add the water. On medium/high heat to bring fruit to a boil, stirring it frequently. Reducing the heat to Medium, and simmer about 20 minutes. Stir it occasionally to make sure it doesn’t scorch.
Mash or blend fruit to get the consistency you want. Keeping more fruit bits makes it more like a marmalade. Blending it more will give you a jam consistency.
Add the juice from one orange to the fruit.
Pour sugar into the fruit mixture, and gave it a good stir. Turn the heat back up to medium to bring it back up to a simmer. Let the jam simmer for 30 minutes stirring continuously so the sugar wouldn’t’ burn. The marmalade will thicken as it cools
The marmalade will keep for 2 - 3 months in the refrigerator or you can Water Bath can it.
You could substitute 1 1/2 C honey instead of sugar.
If you choose to can the marmalade for later, process it in a Water Bath canner for 30 mins. You can follow my canning guide here.