I have fixed cars for many years but ,for personal reasons I need a second opinion. 2003 Nissan Frontier ( 4 cylinder , manual); It cranks too slowly to start. It ran fine a few hours before. I disconnected the battery and connected a known good battery with good copper jumpers. Same story , it cranks too slow to start and in about 5 seconds a bit of smoke came from one cable end , the cables were hot but you could touch them ( about 110 F ). Repeat ,same results but no smoke ( I guess whatever was on the old cables was gone). The only thing I can think is that the starter has failed and is pulling a lot of current. Other opinions?
Since you mentioned it is manual, try to verify if it is the engine that is too hard to rotate (I don't know of possible reasons to that) like that:
1- Try to start the car by pushing while on first gear and then releasing the clutch, does it start easily?
2- Drive the car normally and feel the engine braking (how it deaccelerate without brakes), is it harder than you experinced it before the problem or on similar cars?
That should give you a clue to if it was the starter or the engine, roughly.
Or do like what Autozone would do, replace everything starting from the cheapest component, or so I heard ;)
Can you turn the engine over normally at the crank with a bar etc, or is the engine itself very tight to turn over? If so the issue is not with the starter but the engine itself.
If the engine rotates ok by hand with just its normal mechanical compression resistance etc, then the starter/solenoid may well be the issue. So instead of using a normal amount of current to turn it and the engine over.. its stuck/sticking creating a far higher mechanical and electrical resistance.
But before you swap the starter .. Check that all the main starter leads are good and have tight connections, and that the starter itself is tightly bolted to the engine, also check that the vehicles engine earth strap is good and connected properly. If everything is good, then the starter/solenoid likely has issues.
Good input, I was wrong but I have a good excuse. I tried again after leaving a trickle charger on all night : The battery exploded ( tops blew off ) when I turned the key. Put in a new battery and found the cable ends were much more corroded than they looked, replaced one and it cranked slow but started in about a second. The jumper cables had felt warm because the nerves in my palms ( and soles of my feet) are messed up by chemotherapy. These are common side affects of the drug cisplatin. Basically the cable ends had electric resistance.