cypher

Hey all,

Need some advice from the electrical guys on this one. My jeep has been having a harder time starting in the last week or so. I went to the store today and when I came out it wouldn't start. I let it sit for about 10-15 mins and tried again. It barely turned over but it caught. I thought it was the battery so I had it tested and it was fine, 14.4 v. Then I had the alternator tested and it was only putting out 43 amps, and it's a 90 amp alternator that I just got back on August 8th of this year.

So I was able to get a new 120 amp alternator (I had been planning on getting the bigger one anyway) and installed it. It fired right up with no issue. I took off and went about a 1/4 mile down the road to another store, came out and went to start it. At first it just bogged. No clicking from the starter or anything and wouldn't start. I tried again and goosed the gas a bit and it just barely caught. The battery is only a couple months old and the alt is new as of today.
So, could it be the starter? Any ideas would much appreciated guys, thanks.

Dreamer

Weird, I'm having the same issue. Mine usually will kick over but its unpredictable.

CrazyMacaw

Have you checked the following things?
1 Electrical connections at starter are clean and tight.
2 Cables to starter are in good condition.
3 Battery terminal connectors are in good shape.
4 Starter mounting bolts are tight.
5 Starter relay in PDC.

If you've recently been off road/muddin it's possible your starter got packed with mud or debris.

cypher

No off roading here. My jeep is in no condition to be off road. And I only drive it once or twice a week anyway. As far as your list goes....
1. Tight yes, clean no. It's a mess down there.
2. Cables aren't too bad.
3. Terminals are good.
4. Mounting bolts are good and tight.
5. Starter relay...not checked.
'Nother dumb qeustion....what's the PDC?

The main reason I'm thinking the starter is toast is because when I try to turn the engine over, the starter just bogs and quits. No tell tale clicking like you get with a dead battery. I'll check the other stuff when it's not raining and snowing outside. Too damn raw out today.
Thanks for pointing out those items to look at. I appreciate it.

CrazyMacaw

The PDC is the Power Distribution Center, it's located in the engine bay. It has various fuses and relays in it for things like the Ignition system, fuel pump, Auto Shutdown Relay, Starter Relay. It's a black rectangle box near the battery, it has a cover on it so you won't see the relays or fuses just by opening the hood.
Looks like this with cover removed-


Also just fyi here's a schematic of a typical starting system -


It may well be the starter, but it's easier to check a few items like relays and connections then to yank a starter and I always leave the harder stuff for last...lol.

cypher

yeah, I knew what it was as I was typing it...dumb@$$ that I am. Only reason I asked is around here where I live, you'd be surprised how many people mix up the PCM and PDC. Thanks for posting the schematic of the starting system, that's great. I'll start checking the PDC in the next couple of days to see what I can see.
Thanks again guys.

Coolchange

Just change the starter. I went through that with mine, on the bench it worked, but intermitant in the car. I also added a wire to the solenoid energize terminal while it was out that runs up to the battery. If I have another problem I can just jump it to the battery and bypass all the relays etc.

cypher

Yeah, I was planning on just changing it out. Easier that way and I know it'll be new. Now for another dumb question...can a bad starter drain the battery, either while it's running or turned off?
Thanks for all the info too guys, I appreciate it.