I am a bit unsure now. Checked every connection and found no problems there.
Cleaned battery connections but they looked ok.



Measured only 11.53 Volts on the battery when car not running. It dropped to
11.23 when car was running. Battery tester showed battery as "weak".



Checked another battery in my tractor and it measured 12.2 Volts not running
and battery tester showed "Good".



Voltmeter in car shows some charging, borderline red mark.



Attached a battery charger and it seems to struggle a bit putting some juice
into the battery. On its lowest setting the meter shows about 10 amps and
that's a bit abnormal. I tried this also with battery disconnected from car
but no difference.



The battery in my car is a Sonnak Exide, same technology as Optima. It is
maybe 6-8 years old. Battery in my tractor is an Optima red top.


regards
Odd-Inge



"Odd-Inge Larsen" <oddingelarsen@dcpost.no> wrote in message
news:f5k6hg$ckd$1@troll.powertech.no...
> Noticed today that my voltmeter was well in the red while driving to the
> store. No problem starting yet but only drove 3 km.
>
> This is on a 1990 Jeep Cherokee 4.0L
>
> Something like this happend some years ago and then I had to get a new
> alternator. Suspect the same this time, but would like some tips on what
> to check before ordering a new alternator or having a mechanic check this
> out.
>
> I have a battery tester and a multimeter at hand. I plan to first check
> the battery with the tester to see if it works ok with load. Then measure
> battery volts when the car is not running (should be something like 12V)
> and when car is running (should be higher, preferably 14.4V).
>
> Of course I will try cleaning battery connections (Optima red top battery,
> some years old).
>
> Anything else I could check?
>
> regards
> Odd-Inge Larsen
> North Norway
>

 

I am a bit unsure now. Checked every connection and found no problems there.
Cleaned battery connections but they looked ok.



Measured only 11.53 Volts on the battery when car not running. It dropped to
11.23 when car was running. Battery tester showed battery as "weak".



Checked another battery in my tractor and it measured 12.2 Volts not running
and battery tester showed "Good".



Voltmeter in car shows some charging, borderline red mark.



Attached a battery charger and it seems to struggle a bit putting some juice
into the battery. On its lowest setting the meter shows about 10 amps and
that's a bit abnormal. I tried this also with battery disconnected from car
but no difference.



The battery in my car is a Sonnak Exide, same technology as Optima. It is
maybe 6-8 years old. Battery in my tractor is an Optima red top.


regards
Odd-Inge



"Odd-Inge Larsen" <oddingelarsen@dcpost.no> wrote in message
news:f5k6hg$ckd$1@troll.powertech.no...
> Noticed today that my voltmeter was well in the red while driving to the
> store. No problem starting yet but only drove 3 km.
>
> This is on a 1990 Jeep Cherokee 4.0L
>
> Something like this happend some years ago and then I had to get a new
> alternator. Suspect the same this time, but would like some tips on what
> to check before ordering a new alternator or having a mechanic check this
> out.
>
> I have a battery tester and a multimeter at hand. I plan to first check
> the battery with the tester to see if it works ok with load. Then measure
> battery volts when the car is not running (should be something like 12V)
> and when car is running (should be higher, preferably 14.4V).
>
> Of course I will try cleaning battery connections (Optima red top battery,
> some years old).
>
> Anything else I could check?
>
> regards
> Odd-Inge Larsen
> North Norway
>

 

I am a bit unsure now. Checked every connection and found no problems there.
Cleaned battery connections but they looked ok.



Measured only 11.53 Volts on the battery when car not running. It dropped to
11.23 when car was running. Battery tester showed battery as "weak".



Checked another battery in my tractor and it measured 12.2 Volts not running
and battery tester showed "Good".



Voltmeter in car shows some charging, borderline red mark.



Attached a battery charger and it seems to struggle a bit putting some juice
into the battery. On its lowest setting the meter shows about 10 amps and
that's a bit abnormal. I tried this also with battery disconnected from car
but no difference.



The battery in my car is a Sonnak Exide, same technology as Optima. It is
maybe 6-8 years old. Battery in my tractor is an Optima red top.


regards
Odd-Inge



"Odd-Inge Larsen" <oddingelarsen@dcpost.no> wrote in message
news:f5k6hg$ckd$1@troll.powertech.no...
> Noticed today that my voltmeter was well in the red while driving to the
> store. No problem starting yet but only drove 3 km.
>
> This is on a 1990 Jeep Cherokee 4.0L
>
> Something like this happend some years ago and then I had to get a new
> alternator. Suspect the same this time, but would like some tips on what
> to check before ordering a new alternator or having a mechanic check this
> out.
>
> I have a battery tester and a multimeter at hand. I plan to first check
> the battery with the tester to see if it works ok with load. Then measure
> battery volts when the car is not running (should be something like 12V)
> and when car is running (should be higher, preferably 14.4V).
>
> Of course I will try cleaning battery connections (Optima red top battery,
> some years old).
>
> Anything else I could check?
>
> regards
> Odd-Inge Larsen
> North Norway
>

 

I did charge the battery. Seems ok now. Probably just low due to alternator
failing.

Did try to knock on the alternator with a rubber mallet. This probably moved
the brushes some and the voltmeter jumped to about 14 volts, its normal
position. But it fluctuated a great deal and the interior lights flickered a
lot. Revved it up and it was not able to charge anymore. Let off the
throttle and it charged again.

My diagnoses: Worn brushes in the alternator. Replace brushes or by new
alternator.

Does this seem like a reasonable diagnosis?

regards
Odd-Inge

"Odd-Inge Larsen" <oddingelarsen@dcpost.no> wrote in message
news:f5k6hg$ckd$1@troll.powertech.no...
> Noticed today that my voltmeter was well in the red while driving to the
> store. No problem starting yet but only drove 3 km.
>
> This is on a 1990 Jeep Cherokee 4.0L
>
> Something like this happend some years ago and then I had to get a new
> alternator. Suspect the same this time, but would like some tips on what
> to check before ordering a new alternator or having a mechanic check this
> out.
>
> I have a battery tester and a multimeter at hand. I plan to first check
> the battery with the tester to see if it works ok with load. Then measure
> battery volts when the car is not running (should be something like 12V)
> and when car is running (should be higher, preferably 14.4V).
>
> Of course I will try cleaning battery connections (Optima red top battery,
> some years old).
>
> Anything else I could check?
>
> regards
> Odd-Inge Larsen
> North Norway
>

 

I did charge the battery. Seems ok now. Probably just low due to alternator
failing.

Did try to knock on the alternator with a rubber mallet. This probably moved
the brushes some and the voltmeter jumped to about 14 volts, its normal
position. But it fluctuated a great deal and the interior lights flickered a
lot. Revved it up and it was not able to charge anymore. Let off the
throttle and it charged again.

My diagnoses: Worn brushes in the alternator. Replace brushes or by new
alternator.

Does this seem like a reasonable diagnosis?

regards
Odd-Inge

"Odd-Inge Larsen" <oddingelarsen@dcpost.no> wrote in message
news:f5k6hg$ckd$1@troll.powertech.no...
> Noticed today that my voltmeter was well in the red while driving to the
> store. No problem starting yet but only drove 3 km.
>
> This is on a 1990 Jeep Cherokee 4.0L
>
> Something like this happend some years ago and then I had to get a new
> alternator. Suspect the same this time, but would like some tips on what
> to check before ordering a new alternator or having a mechanic check this
> out.
>
> I have a battery tester and a multimeter at hand. I plan to first check
> the battery with the tester to see if it works ok with load. Then measure
> battery volts when the car is not running (should be something like 12V)
> and when car is running (should be higher, preferably 14.4V).
>
> Of course I will try cleaning battery connections (Optima red top battery,
> some years old).
>
> Anything else I could check?
>
> regards
> Odd-Inge Larsen
> North Norway
>

 

I did charge the battery. Seems ok now. Probably just low due to alternator
failing.

Did try to knock on the alternator with a rubber mallet. This probably moved
the brushes some and the voltmeter jumped to about 14 volts, its normal
position. But it fluctuated a great deal and the interior lights flickered a
lot. Revved it up and it was not able to charge anymore. Let off the
throttle and it charged again.

My diagnoses: Worn brushes in the alternator. Replace brushes or by new
alternator.

Does this seem like a reasonable diagnosis?

regards
Odd-Inge

"Odd-Inge Larsen" <oddingelarsen@dcpost.no> wrote in message
news:f5k6hg$ckd$1@troll.powertech.no...
> Noticed today that my voltmeter was well in the red while driving to the
> store. No problem starting yet but only drove 3 km.
>
> This is on a 1990 Jeep Cherokee 4.0L
>
> Something like this happend some years ago and then I had to get a new
> alternator. Suspect the same this time, but would like some tips on what
> to check before ordering a new alternator or having a mechanic check this
> out.
>
> I have a battery tester and a multimeter at hand. I plan to first check
> the battery with the tester to see if it works ok with load. Then measure
> battery volts when the car is not running (should be something like 12V)
> and when car is running (should be higher, preferably 14.4V).
>
> Of course I will try cleaning battery connections (Optima red top battery,
> some years old).
>
> Anything else I could check?
>
> regards
> Odd-Inge Larsen
> North Norway
>

 

I did charge the battery. Seems ok now. Probably just low due to alternator
failing.

Did try to knock on the alternator with a rubber mallet. This probably moved
the brushes some and the voltmeter jumped to about 14 volts, its normal
position. But it fluctuated a great deal and the interior lights flickered a
lot. Revved it up and it was not able to charge anymore. Let off the
throttle and it charged again.

My diagnoses: Worn brushes in the alternator. Replace brushes or by new
alternator.

Does this seem like a reasonable diagnosis?

regards
Odd-Inge

"Odd-Inge Larsen" <oddingelarsen@dcpost.no> wrote in message
news:f5k6hg$ckd$1@troll.powertech.no...
> Noticed today that my voltmeter was well in the red while driving to the
> store. No problem starting yet but only drove 3 km.
>
> This is on a 1990 Jeep Cherokee 4.0L
>
> Something like this happend some years ago and then I had to get a new
> alternator. Suspect the same this time, but would like some tips on what
> to check before ordering a new alternator or having a mechanic check this
> out.
>
> I have a battery tester and a multimeter at hand. I plan to first check
> the battery with the tester to see if it works ok with load. Then measure
> battery volts when the car is not running (should be something like 12V)
> and when car is running (should be higher, preferably 14.4V).
>
> Of course I will try cleaning battery connections (Optima red top battery,
> some years old).
>
> Anything else I could check?
>
> regards
> Odd-Inge Larsen
> North Norway
>

 

Yup, the mallet trick sometimes tells all.

Hopefully you got it before the slip rings got damaged.

I would do one more test just to see if the mallet did something else.
I would run a battery booster cable from the battery negative to the
alternator case and see if the charging goes stable. If so, the
alternator case would have a bad ground that the hit moved slightly. It
is a sneaky one, but seems to happen on Jeeps a lot.

Mike
86/00 CJ7 Laredo, 33x9.5 BFG Muds, 'glass nose to tail in '00
88 Cherokee 235 BFG AT's - Gone to the rust pile...
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)

Odd-Inge Larsen wrote:
> I did charge the battery. Seems ok now. Probably just low due to alternator
> failing.
>
> Did try to knock on the alternator with a rubber mallet. This probably moved
> the brushes some and the voltmeter jumped to about 14 volts, its normal
> position. But it fluctuated a great deal and the interior lights flickered a
> lot. Revved it up and it was not able to charge anymore. Let off the
> throttle and it charged again.
>
> My diagnoses: Worn brushes in the alternator. Replace brushes or by new
> alternator.
>
> Does this seem like a reasonable diagnosis?
>
> regards
> Odd-Inge
>
> "Odd-Inge Larsen" <oddingelarsen@dcpost.no> wrote in message
> news:f5k6hg$ckd$1@troll.powertech.no...
>> Noticed today that my voltmeter was well in the red while driving to the
>> store. No problem starting yet but only drove 3 km.
>>
>> This is on a 1990 Jeep Cherokee 4.0L
>>
>> Something like this happend some years ago and then I had to get a new
>> alternator. Suspect the same this time, but would like some tips on what
>> to check before ordering a new alternator or having a mechanic check this
>> out.
>>
>> I have a battery tester and a multimeter at hand. I plan to first check
>> the battery with the tester to see if it works ok with load. Then measure
>> battery volts when the car is not running (should be something like 12V)
>> and when car is running (should be higher, preferably 14.4V).
>>
>> Of course I will try cleaning battery connections (Optima red top battery,
>> some years old).
>>
>> Anything else I could check?
>>
>> regards
>> Odd-Inge Larsen
>> North Norway
>>
>
>

 

Yup, the mallet trick sometimes tells all.

Hopefully you got it before the slip rings got damaged.

I would do one more test just to see if the mallet did something else.
I would run a battery booster cable from the battery negative to the
alternator case and see if the charging goes stable. If so, the
alternator case would have a bad ground that the hit moved slightly. It
is a sneaky one, but seems to happen on Jeeps a lot.

Mike
86/00 CJ7 Laredo, 33x9.5 BFG Muds, 'glass nose to tail in '00
88 Cherokee 235 BFG AT's - Gone to the rust pile...
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)

Odd-Inge Larsen wrote:
> I did charge the battery. Seems ok now. Probably just low due to alternator
> failing.
>
> Did try to knock on the alternator with a rubber mallet. This probably moved
> the brushes some and the voltmeter jumped to about 14 volts, its normal
> position. But it fluctuated a great deal and the interior lights flickered a
> lot. Revved it up and it was not able to charge anymore. Let off the
> throttle and it charged again.
>
> My diagnoses: Worn brushes in the alternator. Replace brushes or by new
> alternator.
>
> Does this seem like a reasonable diagnosis?
>
> regards
> Odd-Inge
>
> "Odd-Inge Larsen" <oddingelarsen@dcpost.no> wrote in message
> news:f5k6hg$ckd$1@troll.powertech.no...
>> Noticed today that my voltmeter was well in the red while driving to the
>> store. No problem starting yet but only drove 3 km.
>>
>> This is on a 1990 Jeep Cherokee 4.0L
>>
>> Something like this happend some years ago and then I had to get a new
>> alternator. Suspect the same this time, but would like some tips on what
>> to check before ordering a new alternator or having a mechanic check this
>> out.
>>
>> I have a battery tester and a multimeter at hand. I plan to first check
>> the battery with the tester to see if it works ok with load. Then measure
>> battery volts when the car is not running (should be something like 12V)
>> and when car is running (should be higher, preferably 14.4V).
>>
>> Of course I will try cleaning battery connections (Optima red top battery,
>> some years old).
>>
>> Anything else I could check?
>>
>> regards
>> Odd-Inge Larsen
>> North Norway
>>
>
>

 

Yup, the mallet trick sometimes tells all.

Hopefully you got it before the slip rings got damaged.

I would do one more test just to see if the mallet did something else.
I would run a battery booster cable from the battery negative to the
alternator case and see if the charging goes stable. If so, the
alternator case would have a bad ground that the hit moved slightly. It
is a sneaky one, but seems to happen on Jeeps a lot.

Mike
86/00 CJ7 Laredo, 33x9.5 BFG Muds, 'glass nose to tail in '00
88 Cherokee 235 BFG AT's - Gone to the rust pile...
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)

Odd-Inge Larsen wrote:
> I did charge the battery. Seems ok now. Probably just low due to alternator
> failing.
>
> Did try to knock on the alternator with a rubber mallet. This probably moved
> the brushes some and the voltmeter jumped to about 14 volts, its normal
> position. But it fluctuated a great deal and the interior lights flickered a
> lot. Revved it up and it was not able to charge anymore. Let off the
> throttle and it charged again.
>
> My diagnoses: Worn brushes in the alternator. Replace brushes or by new
> alternator.
>
> Does this seem like a reasonable diagnosis?
>
> regards
> Odd-Inge
>
> "Odd-Inge Larsen" <oddingelarsen@dcpost.no> wrote in message
> news:f5k6hg$ckd$1@troll.powertech.no...
>> Noticed today that my voltmeter was well in the red while driving to the
>> store. No problem starting yet but only drove 3 km.
>>
>> This is on a 1990 Jeep Cherokee 4.0L
>>
>> Something like this happend some years ago and then I had to get a new
>> alternator. Suspect the same this time, but would like some tips on what
>> to check before ordering a new alternator or having a mechanic check this
>> out.
>>
>> I have a battery tester and a multimeter at hand. I plan to first check
>> the battery with the tester to see if it works ok with load. Then measure
>> battery volts when the car is not running (should be something like 12V)
>> and when car is running (should be higher, preferably 14.4V).
>>
>> Of course I will try cleaning battery connections (Optima red top battery,
>> some years old).
>>
>> Anything else I could check?
>>
>> regards
>> Odd-Inge Larsen
>> North Norway
>>
>
>