So i bought a 1995 civic Lx with a blown engine. I thought i would just buy a another used engine and swap it in there and have it back on its wheels again. i replaced the engine. And i went to crank the engine and its very slow to crank. I did throw in new parts and made sure all my fluids were at appropriate levels. I would try and start it and it would crank so slowly and then stop. i checked battery and it was at 12v with a multi meter. i checked all power and grounds. i did recharge the battery and it would start for a couple seconds then die out again. i did check fuel and the injectors found i had a leaking injector replaced it. right now im waiting for the battery to charge so if anyone has suggestion would help

list of parts bought :
belts
battery
starter
spark plugs
plug wires
distributor cap and rotor
vacuum hoses
fuel injector