i redid the test and took pictures:

Meter Settings:
The + probe needs to be plugged into the other port bc the one below it has a MAX of 200mA.



The probes in positions:



Results:



Am I doing this correctly?

Perhaps my meter is junk??

I am going to throw the car in a 10a charge for about an hour--hour and a half..


Kris

I think Brian is having a beef with the numbers simply becuase on the 10Amp mode is not as accurate as teh other modes.

I think Kris you can put your meter in 200mA mode and then measure it (it will be more accurate)

Just be careful not to draw too much load and make sure your fuse is not blown (inside the meter).

I think autozone was full of crap when they did the test. Probably used a inductive tester and had it connected wrong/to the wrong wire?

You definitely need the meter on the 200ma scale. The reading should stay within this range. If it goes over 200ma, then it's time to start pulling fuses, one at a time, until it drops into a more normal range................50-75ma.

Make sure all the doors are closed and the trunk is closed. Nothing should be on inside the vehicle.

i think you are correct when u say their test was bad...

the first test was @ Advance Auto = .03 Amp producted by alt
the 2nd test was @ AutoZone = 149 Peak Amps producted by alt.

I will check my meter and retry the draw test at 200ma.

thanks guys

kris

my fuse was gone in my meter...i dont have any 5a spares...i have a 9a thou...hmm

Hmmm...149 peak amps? Impressive for a 65Amp alternator!

That aside...I think either you have a BIG load on the battery sometimes or you have a grounding issue.

How is the water level in your batt?

umm water level...how woud i check for this interstate battery ?

well i do have the subs's power wire coming off the battery

amps:
Power Acoustik TS1440-2 300watts x2 @4ohms
Kenwood 50w x 4 @ 4 ohms

I am taking the car up tomorrow to my mechanic's and going to have him test the alternator and see what he thinks....

the fact that the car ate 3 batteries in 5-6 years probably means there is something causing the batteries to die...

Could the alternator be working intermittently? Sometimes working at normal power and sometimes working at extremely low?

I'll need to get another 5a fuse for my meter to check @ 200ma for the power drain...


thanks

kris

If it is a maintenece free battery, there is no levels to check. Was just a thought.

ALso the alternator COULD be working intermittantly but from all the testing you have done, I see no indication of it doing so yet. Put your volt meter between the negative post on the battery and then ground the other probe to the engine somewhere.

Put it in voltage mode and start the car...watch it while starting.

If you measure much of any voltage...that means your body to engine ground strap is not connected/broken/poor contact.

Have you checked the rest of the big power wires?

the end of this problem is now here.

Ive taken the car up to my MB Mech's shop...it was tested and put out 45-50 amps when the engine was revved up..volts were good also...the only problem that was seen was that the ground wire was a little loose other than that nothing..if the problem is intermittent it will show up again and ill be ready.i also got a new multimeter.

nifty little thing can test for voltage w/o probes! (not # of volt just presence)


-kris

thanks everyone

Question...did I read somewhere that some MB alternators won't begin to charge until 1,500 rpm is reached....can't find it right now but thought I saw that somewhere as messed up as that sounds...just a thought.

__________________
1983 300SD... 269,000 miles, nearly 2,500 on my B-100, Faded Grey, Ugly in an elegant sort of way...Duh-Benz


If any of this has been a blasphemy to you, then good, because it's been a blast for me to...A.Whitney Brown

Mine seems to put about 13.5V to the battery at idle.

I think he is thinking of VW alternators. I remember seeing something about them not turning at idle or something...

my alt puts bout 13.5-13.8 at idle

do the 13.5 at idle on any car with an alternator. one of the reasons for the switch from generators to alternators (im old enough to remember when they switched over) was that they put out nearly max at idle. generators dont.

tom w

__________________
[SIGPIC] Diesel loving autocrossing grandpa Architect. 08 Dodge 3/4 ton with Cummins & six speed; I have had about 35 benzes. I have a 39 Studebaker Coupe Express pickup in which I have had installed a 617 turbo and a five speed manual.[SIGPIC]

..I also have a 427 Cobra replica with an aluminum chassis.

VW Gen's don't require a "kick" to start them...thats the beauty of generators.

Anywho, SOMETIMES you have to get the RPM on the alternator up just a tad above a slow idle to get it to start outputting.

If the engine doesn't break a certain RPM when started, the alternator MAY not necessisarily see all the speed it needs to start. Once it starts though it is fine.

Alternators don't put out MAX at idle whatsoever. They put out quite a bit more than a compareable generator at idle but by no means their full juice.

You can check the water level on that battery, I have one just like it. Pry off the two plastic "strips" under the handle. Each of them is a cap for three cells. They just pop off with a small screw driver.