Jeep Alternator / Charging System

My son's 91 jeep Cherokee/Laredo broke down yesterday because of a
lack of electricity. He mentioned on the phone when he called that
the voltmeter on the dash was down around 9 volts. So after getting
it home and charging the battery, I had him start it and then removed
the negative cable while the engine was running and the jeep quit
immediately once I lifted the negative cable (used to be one of the
easiest ways to rule in or rule out a charging system problem).

As it turns out, the regulator is internal to the alternator and my
big question is, how do you replace the alternator on this vehicle? It
doesn't look fun or easy from any level (under the fender well, under
the car, from the top)... Hoped that someone might have a manual and
wouldn't mind looking it up or otherwise, find someone that has
replaced one of these alternators. It's located below the AC
compressor on the passenger side.

It's been kind of a fun rig for him but he's to a point where he wants
to get the charging system running and then sell the vehicle. Any
help is very much appreciated.

Chris

Just FYI, removing the battery cable on newer vehicles 'usually' ends up
costing thousands of dollars because all the computer parts fry almost
instantly with unregulated power.

My old tenant had a so called High End stereo shop install his and they
left the negative battery cable loose. This fried the alternator,
stereo, distributor pickup, coil and ignition module on his 92
Cherokee.... Then the same shop did it a second time to him. He was
suing when he unfortunately passed away.

I would first verify the alternator still has a ground path. Jeeps are
notorious for losing that.

I test it with a battery booster cable that I run from the battery
negative to the alternator 'case' to see if the voltage jumps up. I
then take the booster to the vehicle body and engine block to see if
there is any difference.

The alternator bracket is bad for losing the connection where it bolts
to the block. The body is bad for a mesh ground strap that rots between
the engine head and the firewall on the 4.0 engines.

When I change those alternators, I leave the belt adjuster alone unless
I am changing the belt too. The adjuster is a pain and is over under
the PS pump with a sneaky set screw holding the long adjuster bolt.
When the alternator comes off, the belt loosens, when the alternator
goes back on, the belt goes back the same.

The alternator comes out the bottom. Down with a twist.

Mike
86/00 CJ7 Laredo, 33x9.5 BFG Muds, 'glass nose to tail in '00
88 Cherokee 235 BFG AT's
Canadian Off Road Trips Photos: Non members can still view!
Jan/06 http://www.imagestation.com/album/pi...?id=2115147590
(More Off Road album links at bottom of the view page)

cover wrote:
> My son's 91 jeep Cherokee/Laredo broke down yesterday because of a
> lack of electricity. He mentioned on the phone when he called that
> the voltmeter on the dash was down around 9 volts. So after getting
> it home and charging the battery, I had him start it and then removed
> the negative cable while the engine was running and the jeep quit
> immediately once I lifted the negative cable (used to be one of the
> easiest ways to rule in or rule out a charging system problem).
>
> As it turns out, the regulator is internal to the alternator and my
> big question is, how do you replace the alternator on this vehicle? It
> doesn't look fun or easy from any level (under the fender well, under
> the car, from the top)... Hoped that someone might have a manual and
> wouldn't mind looking it up or otherwise, find someone that has
> replaced one of these alternators. It's located below the AC
> compressor on the passenger side.
>
> It's been kind of a fun rig for him but he's to a point where he wants
> to get the charging system running and then sell the vehicle. Any
> help is very much appreciated.
>
> Chris

On Wed, 16 May 2007 07:07:42 -0700, cover
> wrote:

>My son's 91 jeep Cherokee/Laredo broke down yesterday because of a
>lack of electricity. He mentioned on the phone when he called that
>the voltmeter on the dash was down around 9 volts. So after getting
>it home and charging the battery, I had him start it and then removed
>the negative cable while the engine was running

DUMB! If the alternator (and much of the electronics) were not dead
already, they will be after that trick. Never, ever, remove a battery
cable with the engine running.

>and the jeep quit
>immediately once I lifted the negative cable (used to be one of the
>easiest ways to rule in or rule out a charging system problem).
>
>As it turns out, the regulator is internal to the alternator and my
>big question is, how do you replace the alternator on this vehicle?

So you *know* it is the regulator? You can't tell that from
disconnecting the battery, but then what the heck...

On Wed, 16 May 2007 15:23:03 -0400, PeterD > wrote:

>>As it turns out, the regulator is internal to the alternator and my
>>big question is, how do you replace the alternator on this vehicle?
>
>So you *know* it is the regulator? You can't tell that from
>disconnecting the battery, but then what the heck...

Nope, don't "know" that. Only going on what the parts houses said
when they quoted a replacement at ~$140.00 for a rebuilt.

On Wed, 16 May 2007 11:46:18 -0400, Mike Romain >
wrote:

>Just FYI, removing the battery cable on newer vehicles 'usually' ends up
>costing thousands of dollars because all the computer parts fry almost
>instantly with unregulated power.
>
>My old tenant had a so called High End stereo shop install his and they
>left the negative battery cable loose. This fried the alternator,
>stereo, distributor pickup, coil and ignition module on his 92
>Cherokee.... Then the same shop did it a second time to him. He was
>suing when he unfortunately passed away.
>
>I would first verify the alternator still has a ground path. Jeeps are
>notorious for losing that.
>
>I test it with a battery booster cable that I run from the battery
>negative to the alternator 'case' to see if the voltage jumps up. I
>then take the booster to the vehicle body and engine block to see if
>there is any difference.
>
>The alternator bracket is bad for losing the connection where it bolts
>to the block. The body is bad for a mesh ground strap that rots between
>the engine head and the firewall on the 4.0 engines.
>
>When I change those alternators, I leave the belt adjuster alone unless
>I am changing the belt too. The adjuster is a pain and is over under
>the PS pump with a sneaky set screw holding the long adjuster bolt.
>When the alternator comes off, the belt loosens, when the alternator
>goes back on, the belt goes back the same.
>
>The alternator comes out the bottom. Down with a twist.
>
>Mike
>86/00 CJ7 Laredo, 33x9.5 BFG Muds, 'glass nose to tail in '00
>88 Cherokee 235 BFG AT's
>Canadian Off Road Trips Photos: Non members can still view!
>Jan/06 http://www.imagestation.com/album/pi...?id=2115147590
>(More Off Road album links at bottom of the view page)
>

Thank You Sir... Will look at some of the things you mention, maybe
luck out and not have to change it.

I'm sorry I can't help you with the alternator question, but I would
like to say:

Please be careful working around the battery. Anytime you are charging
an automotive battery, there is the potential for explosive gasses.
Pulling any cable off the battery that could create a spark is asking
for an explosion- which I have seen twice, and don't care to see again.

If you want to check for a charge or draw on the battery, you should
check out an inductive amp-clamp type of meter. It will tell you
exactly what is going on, very quickly.

Please be safe!

And, good luck,
Clay
cover wrote:
> My son's 91 jeep Cherokee/Laredo broke down yesterday because of a
> lack of electricity. He mentioned on the phone when he called that
> the voltmeter on the dash was down around 9 volts. So after getting
> it home and charging the battery, I had him start it and then removed
> the negative cable while the engine was running and the jeep quit
> immediately once I lifted the negative cable (used to be one of the
> easiest ways to rule in or rule out a charging system problem).
>
> As it turns out, the regulator is internal to the alternator and my
> big question is, how do you replace the alternator on this vehicle? It
> doesn't look fun or easy from any level (under the fender well, under
> the car, from the top)... Hoped that someone might have a manual and
> wouldn't mind looking it up or otherwise, find someone that has
> replaced one of these alternators. It's located below the AC
> compressor on the passenger side.
>
> It's been kind of a fun rig for him but he's to a point where he wants
> to get the charging system running and then sell the vehicle. Any
> help is very much appreciated.
>
> Chris

do not sell.
old john

Hello, cover!
You wrote on Wed, 16 May 2007 07:07:42 -0700:

c> As it turns out, the regulator is internal to the alternator and my
c> big question is, how do you replace the alternator on this vehicle? It
c> doesn't look fun or easy from any level (under the fender well, under
c> the car, from the top)... Hoped that someone might have a manual and
c> wouldn't mind looking it up or otherwise, find someone that has
c> replaced one of these alternators. It's located below the AC
c> compressor on the passenger side.

c> It's been kind of a fun rig for him but he's to a point where he wants
c> to get the charging system running and then sell the vehicle. Any
c> help is very much appreciated.


With best regards, . E-mail:

Do you happen to remember if the battery and battery tray need to be
removed? Looks as though access to that top bolt would be much easier
if they were removed THOUGH... removing them is a pain in the butt.
:-)

On Wed, 16 May 2007 21:11:44 -0700, > wrote:

>do not sell.
>old john
>

Why not, Old John? If for no other reason, insurance costs too much
when they hear the word, 'jeep'. ;-)

cover wrote:
> Do you happen to remember if the battery and battery tray need to be
> removed? Looks as though access to that top bolt would be much easier
> if they were removed THOUGH... removing them is a pain in the butt.
> :-)

I recently stripped a Cherokee engine bay down in prep for replacing
with the engine from our current rustbucket, but had to get rid of it
instead (the local government had a warrant to come and steal it so I
sold it first because I didn't have time to finish it) and don't
remember having any problems at all removing the alternator which I kept
for a spare. I left the battery tray in.....

I do have various extensions for my air powered socket wrench....

If you are bent on selling it, what part of the world are you in, what
shape is it in with how many miles and how much?

Mike
86/00 CJ7 Laredo, 33x9.5 BFG Muds, 'glass nose to tail in '00
88 Cherokee 235 BFG AT's
Canadian Off Road Trips Photos: Non members can still view!
Jan/06 http://www.imagestation.com/album/pi...?id=2115147590
(More Off Road album links at bottom of the view page)