Folks, the cranking is slow but eventually starts the engine. Where's a good place to start to remedy this problem. Battery is new. I purchased my 75 last August with its 302 (factory I6). Unknown of the engine year, so I will be removing the starter to find out. Does the solenoid have anything to do with slow cranking?
I would still test that new battery to be safe. A bad ground or high resistance in either battery cable,bad starter could also cause slow crakning. I would get a charging system test as well. To make sure the alternator is working 100 percent. if you let the vehicle sit for extended periods of time you may have a small electrical current draw weakening tha battery.Good luck!!! I forgot to add internal engine problem but the least likely!!!!!!!
Check the battery voltage while the engine is being cranked - It should stay above 10V. (if it drops below that replace it and begin again) if that is ok then check the voltage at the starter (one lead on the starter + and the neg on a bear spot on the case) It should be the same as the battery volts or no less than a half volt lower. If it checks lower than battery volts minus one-half volt then make the next two checks. If it is lower, then you have to first check the pos. wire for voltage drop - Battery positive (pos lead) to the starter posative (neg lead) and the voltage should be less than one half volt) (If it is more don't replace it yet) If that is over one-half volt then check the voltage across the battery terminals of the solenoid. Battery + (pos lead) to starter lead at the solenoid and negative lead to the terminal with the cable to the starter.) If it is one-half volt or more replace it and redo the previous check. If it is still over one-half volt then replace the cable. and recheck the voltage at the starter - if that is still low then replace the starter. Cables should be at least #4 AWG but #2 AWG is better. replace any non molded battery cables and starter cables and make sure the battery is fully charged before you start these tests. (those screw down emergency battery terminals should only be use as long as it takes you to get to a place where you can put good ones back on - no more than a week. The corrosion is there because they don't make good connections. You should have a ground lead to the frame and another one (the same size) to the engine block.
