The best things i have found to repair all manner of faults is, e-metal, black nasty and green string, i have patched up multiple holes is engines, gearboxes and axles with e-metal.
fulcrum seals are a common thing to go on mmlc, so if needed the oep 220 is drained and replaced with grease.
my old man had a s3 landrover that became detached from its fuel tank after being filled up as the straps where rusted through, his boat fuel can soon found its self being transferred between the 2 for the rest of the time he owned it.