Logic Masters Deutschland e.V.

This is my third puzzle using the internal loop x-sums. The previous puzzles in this series are linked to below:
Internal X-Sum Whisper Loop
Internal X-Sum Entropic Loop

Rules:
Normal Sudoku rules apply.

Draw a one-cell-wide loop of orthogonally connected cells. The loop may not touch itself, not even diagonally.

The loop acts as a modular line. Each set of three adjacent digits along the loop must be one each from the sets [147], [258], and [369].

Cells with an arrow clue act as internal loop x-sum clues: a digit in a clued cell indicates the sum of the first X digits on the loop in the indicated direction, where X is the digit in the first loop cell in that direction (not including the clued cell itself). X cannot be larger than the number of loop cells in the indicated direction, and the clued cell may or may not be on the loop.