I've got an interesting one. I think I know the answer but lets hear what you all have to say. When I start my CJ, normally it cranks right up. Rarely though, I have to give it another try. First crank is normal speed always but the second try usually sounds like the battery is about to die and it cranks real slow. This has happened for years and I want to finally figure it out. (I know, but hey if my Jeep was perfect, I'd have to complain about my wife.) Another symptom related or not is that in the past 6 months I've noticed my battery tray has been growing that white powder in the base of my battery tray. My guess is I have a ground that needs attention, probably between the frame and the engine and the body and the frame too. She is 27 and not accustomed to life in the Northeast. Anyone venture a guess or know something I don't?
Doug, Both cables from the battery are newish and so is the cable from the solenoid to the starter....This is what leads me to think I have a ground issue. Also, I've been reading about my corrosion on the battery and everything leads me to believe I have a charging issue with my alternator. It runs close to 16V at idle on my voltage gauge (autometer) when all electrical circuits are off. I haven't checked it with a real voltmeter yet, but I suspect I might need an alternator too.That voltage has been creeping up over the last 6 months.
I had a similar problem on my 84 CJ7. Turned out to be a bad ground. I found this when I had a friend helping me out with replacing plugs. He was looking into the engine compartment and asked why I had a light in there that turned on when I cranked it. Turns out, sitting outside for some time really corroded the ground connection to the frame. It was arcing across the bolt. After I took a wire wheel to both the bolt and the frame, it turned over like a champ. And I agree completely about the northeast. My CJ doesn't like it either.
Mine acts like that, with the high voltage on the gauge also when I get a punky connection. Got one right now I need to track down.
It is 'usually' the ground path on mine also, but sometimes it is just a polished up fan belt. To check the belt, I take a cold off engine and see if I can make the alternator pulley slip by hand under the belt. If I can, it is new belt time.
I think that is going to be my current fix because I also get a low volt gauge reading for a few seconds after starting, then it rises fast up to
15+ V.
If you have a multimeter, you can usually nail the bad connection down using voltage drops. I am thinking your bad connection is in the 'active' part of the circuit due to the 16V reading, vs the 'passive' part that only sees volts when starting.
I start it up, then turn on everything electrical. I then take a volt reading on the back of the alternator, using it's case for ground it's the main post for the power probe.
I next take the meter and read the battery 'terminals themselves. These two readings must be exactly the same.
If they are not, then I start 'walking' the meter probes. I keep the positive on the battery 'post', not clamp and run the negative from the post to the clamp and compare volts, then to the engine block, then to the alternator frame, then to the alternator case, then to the Jeep body where the ground strap goes from the engine head to the firewall, then to the Jeep frame.
Anyplace I find a voltage drop, I have found a connection that needs to be cleaned. The alternator bracket is a sneaky one for bad connections.
I then walk the meter's positive along the same way leaving the meter negative on the battery post.
Hope this helps,
Mike
86/00 CJ7 Laredo, 33x9.5 BFG Muds, 'glass nose to tail > I've got an interesting one. I think I know the answer but lets hear what
Thanks Mike, I was thinking of doing something like that. You confirmed my suspicions. Maybe that is the cause of the 16V reading. THe belt is a serpentine one and is pretty solid. I'm thinking I'm just going to clean and lube with dielectric grease all the major connections and go from there. My alternator is OE with over 200k miles on it, I'd venture to guess it is almost if not ready for the scrap heap too.
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