leadpipe58

Hello All

I have a head scratcher.
I have a 97 Grand Cherokee In line 6 With all the bangs and whistles,Here is the problem.
My Serpente belt squeals when the alternator output is below 14 volts.As soon as it starts charging the belt is quite.It may take 3 minutes for the alt to start charging and it is longer with the headlights on or till it comes up to temp.If I do not have the head lights on it will charge as it should.
It seems to be acting back words.The belt squeals when the Alt is not charging(No Load) and quite when charging (full load).
One other point.randomly the volt gauge will go to zero and the idiot light will light but still charging.Check with meter and does not effect the Jeep at all.I restart and it works again.
I do not know what to check first.
Thanks for any help.
John

jnicewan

Have you check the belt and tensioner? There is a good chance the belt is worn or stretched out or the belt tensioner has failed or is weak.

The volt guage getting low might be due to the concern above if the belt is slipping on the alternator. I dont think the volt guage should go to zero though, if the alternator is slipping or not charging then the guage should still indicate battery voltage. I would at least fix the belt concern first and see what happens.

GI-Jeepin'

x2 on the belt tensioner and belt. The tensioner has marks almost the same as timing marks. The owners manual will tell you how to read the marks to see if the belt is too far stretched.

Also, sometimes when dirt and road grime gets in between the belt and the pulley it can make some wierd noises.

dave1123

Excuse me, but my 97 ZJ 4.0 doesn't have a belt tensioner. It has an adjusting bolt and is very dificult to adjust without a tension guage. My cherokee also had the same voltmeter problem just before the alternator quit entirely.

leadpipe58

Thank you for the input.
I have tightened the belt so there is less than A 1/4" deflection at the longest section.I do not want to crank any tighter for fear of over loading other equipment.
I will change the belt.The way it has slipped it should be changed any way.
What would reset the volt gauge on the dash by restarting it?It should not be a wire type short,restarting should not fix it.
Dave1123 thanks for the heads up.Did it fix the problem?I will make shure my local parts house has an alt for this.
Some FYI I have been A tech on power boats for 23 years with a diesel background and I just do not know Jeep systems to find the bug in my Jeep.
Thanks again for the help and any other ideas.

dave1123

Changing the alt. on my rig stopped the problem with the voltmeter. I even used a junkyard one because I didn't have the cash for a new one at the time. I only paid $15 for it and it's still working.

Jeep has a directive about the dash connector. It seems the dash lighting is AC and it tends to corrode the connector allowing AC current to bleed into other circuits. I know mine is questionable because the lights on the guages keep flashing dim to bright. Sometimes pressing on the control slide switch will end the problem, other times not. Fixing the problem involves cutting out the old connector and soldering in a new one. Not my idea of a good time!

There are certain things I will tolerate and other things drive me crazy! I wish I could eliminate the auto-locking of the doors at 15 mph. They tell me I can turn off the entire security system by grounding it, but nobody has told me how to do it yet.

GI-Jeepin'

Thats why you're the "Member" and I'm still a junior Member!

I should've read up on it first than pass on bad info, that's bad juju on my part.

dave1123

Hey, GI, That's what the forum is for! Passing on personal information because we've been there! ANY input is needed. I probably wouldn't have thought about belt tension if you hadn't mentioned it. With my rig, belt tension is critical. If I get it too tight, I screw up my waterpump, which I've already done. If I get it too loose, I get belt squeal. I wish I had a spring loaded tensioner! Most of the info you post is acurate. Don't put yourself down. I'm only a member because I'm a blabbermouth and am 66 years old! I'm more familiar with carbeurators, and self contained ignition systems. I also have a good electronics background. Vehicles today are getting too damned complicated to keep up with, let alone troubleshoot!

Having run on at the mouth, Leadpipe, let us know what you find out because it will help add to the general fund of info for everyone on the site. I've learned A LOT about my jeep just by reading other guys posts.

Keep on Jeepin'