Ok... Heres my problem. I have a 1987 XJ. When I try to start it, it wont crank, all it does is click, once. I've replaced the starter and the ignition coil, and battery is only 6 mo. old. Any suggestions ?

 

Dirty cables at one end or the other.

 

Here's something to try/rule out...



Battery gasses have a nasty habit of helping a thin, hard crust form on the bat post's and clamps. They can look pretty good, but that micro-thin layer is a surprisingly good insulator. SHINNY! Lead is what you want. I use a pocket knife, (gently), for the insides of the clamps. For the posts I might use one of those post cleaner wire brushes, but still scrape it with a blade. If you have a condition where you have power, (dash lights ect.), then when you hit it power goes out altogether, that's a common result of a layer of oxidization there. Btw, a half *** connection could be expected to get hot during cranking, or while it's trying. Cleaning those is something to do now and then anyway, so if you are having starting problems, you might want to make sure you have bare lead on lead. Might save you some grief!

 

Sounds like the battery.Try jumping it off & cleaning the posts.

 

Short the starter terminals from underneath the jeep with a rubber handle screwdriver,If it doesn't crank then its most likely the battery.

 

Could be the alternator. Cheap test: When the Jeep is off, hold a magnet to your alternator. (Next to/below the battery...right under the AC compressor if you have it). If it doesn't stick, you need a new alternator.

 

What?

 

This..^..,this is your first post?

I smell a troll.

 

Well welcome, but you need to think it through a little more. Yea, nobody asked if his battery is up, signals flash on time, did he jump it? Meter the voltage?

Running or not a magnet will be attracted to the iron in the stator. RUNNING a working alternator becomes a magnet. The regulator energies the rotor to make a magnetic field to sweep through the outer stator windings to create AC current, which is rectified to DC with 3 positive, and three negative diodes. If the rotor is not energised, or is and there is a broken wire or the brushes are toast, it won't, make a field to attract, say, a wrench.

 

This is a joke, right?

 

April Fools was 3 days ago....

 

Perhaps it has nothing to do with April, if you get my drift.

 

 

You guys are silly... (I love it !) . Thanks for the ideas but i had the battery tested , it has a full charge and i replaced the terminals 6 months ago when i bought the battery. The "click" is coming from the coil, or maybe a relay. Would either of those components click if its bad ?

 

Try swapping the ASD relay with a similar one near by. Maybe you're hearing that click, and that would cause it not to start