This 1995 Toyota Celica came in with the complaint that the starter would click but not turn the engine over. The problem was intermittent but getting more frequent according to the customer. I was expecting to find a worn plunger and contacts inside the starter but the starter had recently been replaced. If you think you have contact and plunger issues please click here for more information on that subject.
You will need to click on the following pictures to enlarge them for a better view of the problem. Look carefully at the coloring of the nut that holds the battery cable to the starter post, especially the washer under the nut.
You can see some discoloration of the cable terminal in the next picture.
Even though the next picture is blurry you can clearly see the change in color from the area near the crimp to the upper end of the ring terminal.
Anytime you see discoloration of a fastener on the upper side there is bound to be a deeper problem on the underside.
The coloring of this nut is what I was seeing as I looked up at the starter. Pretty clear this was the problem.
I cleaned the cable terminal and installed a new nut and lock washer.
The tool I used to clean the cable end. I get these here.
Since I was already in cleaning mode, I went ahead and cleaned the battery terminals as well. I cheated on this one though. After a light wire brushing I finished cleaning it in my glass bead cabinet.