At noon they prepared the block for a controlled leak test. Silas insisted that the purpose was to find out whether the repair had actually sealed the damaged passage, not to perform an impressive demonstration for an audience. Dale helped with the test setup and watched Jonah double-check the surfaces before they began. Nobody spoke much once the procedure started, because the gauges and the iron deserved more attention than conversation.
For the first few minutes everything held. Jonah monitored the indicated pressure, then scanned the repaired section with a light while Dale checked the joints and test connections. The shop was quiet except for the low sound of the equipment and a distant truck passing along the county road. Dale had just begun to straighten his back when Jonah saw the tiniest bright bead forming near the lower edge of the casting.
"Stop there," Jonah said. His father looked at the moisture and went pale with disappointment. To him the drop meant they were back at the beginning, with a broken engine block and fewer days before planting. Silas remained seated, waiting to see what Jonah would do now that the test had delivered an answer nobody wanted.
Jonah did not immediately declare the repair a failure. He recorded the pressure and the location of the leak, then let the test conclude safely before cleaning the area to trace where the moisture had actually originated. The wetness seemed close to the repaired fracture, but a careful inspection showed it following a slightly distorted sealing surface near the test fixture rather than emerging between the stitched sections. Jonah checked the surface again and found that its irregularity had been hidden beneath old gasket material during the initial inspection.
Dale watched as his son separated the two possibilities on paper. He could see now why Silas had made Jonah spend so many winter evenings looking at parts that nobody needed; the boy was not simply trying the repair again and hoping for a different outcome. He was asking a narrower question: whether the evidence showed failure in the stitched crack or leakage at a surface that needed separate attention. It was the same distinction that had saved him from forcing the misaligned pin the day before.
They corrected the sealing problem and prepared for another test. Silas checked the setup before allowing the pressure to rise, and Jonah watched the previously damp area with the concentration of someone listening for footsteps in an empty house. Minutes passed. The gauge remained steady, and the surface stayed completely dry.