More thoughts on low starter effort.....
run a lead from battery pos + to the thinner wire connecter at the starter...this should run the starter,if it works better,check the thin wire to the starter for brittleness and good connecter.A wire with a cracked conducter would warm up and expand but give restricted current when cold.Not likely,but.....
Clean the surface of the starter motor : its possible for oil and other crud to accumulate on the outside of the starter,hold moisture and cause a partial short,possible but not likely!This could explain why the problem when first started,ie the heat cooks off the moisture.Even so,its worth the effort of disconnecting battery neg- ,disconnecting cables from starter and giving it a good scrub with a stiff nylon brush and making sure the connecters have bright metal.
Take the main earth off from its body contact and clean so theres bright metal on both body and connecter.Make another earth to the block from the battery neg- : if you dont have air con there are some nice spare threaded holes close by.
Clutching at straws,I know !!Have a listen to the engine bay with the ignition off...hear any whining noise ?Some EDCs whine when off,not sure what it is but its a current drain.It comes on on mine at ignition start position.
...thats all I can think of for now but I'd be interested to hear any results you get
shocksie
