Won’t turn over selnoid just clicks, checked wiring ,bench tested selnoid, I have 12.4 volts to selnoid so wiring must be good, could it be the switch?
Unlikely, the clicking is the power not getting to the starter. Clean the ground on the engine, the starter negative terminal is the body of the engine. Corrosion is not only on batteries, but at any other connections as well. Clean and tighten everything and you should be fine, start there. After that load test the batteries. Even batteries that test 12.4 v can have a shorted cell where they drop to nothing when a load such as a starter is put on them.
12.4 is low, have you charged the battery? is that resting or cranking voltage? HUGE difference. Check voltage under load, it never lies. Go down to page 12 for starters, but read the whole thing. Make some test leads to check cranking voltage from the seat, or get a power probe to simplify the tangles. https://www.gomog.com/allmorgan/LucasFault.pdf
Good info in that pdf Delmer.
Problem solved, I replaced the negative battery cable and it took care of the problem, I cleaned the cable on each end but must have been something in the cable itself
Great to hear, I guess 12.4 is enough to start it after all. That was my first suspect, ground cable.