Starting problem

[xjdavid1]

About 20% of the time when I turn the key to start the xj I hear a click and then nothing. When I try the 2nd time it always starts. When the starter does work it s the engine over at the normal speed. The battery is only 6 months old. Before I start tearing things apart I thought I would ask here. My thoughs are it is either the solenoid of maybe a contact in the starter that is not turning the engine once the ring gear is pulled in. I am assuming that the first click I am hearing is the starter motor ring gear being pulled in. Are there any contacts in the starter motor that maybe accounting for this. Is the solenoid serviceable.

 

[Matthew Currie]

First the solenoid pushes the drive pinion outward, with a spring on the shaft so that it can continue to push out after the pinion is seated. The last thing it does is to bridge a pair of big high current contacts that switch the starter motor on. So one possibility is that these contacts are bad - scorched or eroded. It's not uncommon after a zillion or so miles. I haven't had a Jeep starter apart recently to see how easy it is to fix this. On most starters (Delcos and old Bosches come to mind) the threaded studs that take the main cable connection and the strap to the starter itself have the contacts on their inner heads, so all you need to do is take the solenoid off and remove them, file them down or turn them around, and you're good for a long time. Delcos have square heads, and you can turn them 180 degrees for a second lifetime if they are too eroded just to file flat.

Before you do this, however, make doubly sure that all your battery and cable connections are good and clean, because a corroded battery terminal or a rusty/loose/dirty connection at the starter stud can cause exactly the same symptoms.