Cummins Deisel Battery question update

From : jim lil jim morrisatsk sympatico ca

Q: original question................ i have a 1998 dodge 3500 1 ton dually cummins deisel with two batteries in it...one on each side of the truck engine compartment. i have a groggy starting truck ...it is not a battery drain or short though the night or anything...i have a lemon battery amongst the two or both may be going. this is my question....how do you determine which is the faulty battery or if they are both --------------------------------------end of original question------------------------------------------- thanks again to all that replied to that posting. i took the truck to battery depot and watched them as they did several tests on the charging system...i was told the system was charging normally...was told the alternator was throwing over 14 -15 volts to recharge the batteries.....and i always noted the volt meter on the dash was reading about the same as what they said the alternator was putting out. then they had me shut the truck off and disconnected each battery and did a load test on each...they both failed miserably....they basically cratered is what i expected one battery went to 9 volts after 38 amps was applied....so new batteries were bought 2...i restarted the truck as instructed after the new installation .........the truck fired up better than in the show room the day i bought it... ...but i look at the + and - gauge on my dash and see the battery volt meter on the dash reads below 14 volts lower than it usually had read they take a reading on the alternator and say that the alternator is now only showing 13 volts which is a concern for charging. looking at the volt meter on the dash said the same thing as the needle was lower which was basically at what the guy said...around 13 volts or so .....so they tell me to come back in a few days to see how the alternator is to see if it changes after a few days. so i go to the gym to work out and then have a 25 km drive home from the city on the highway where i see that the charging guage jumped way up and is showing well above 14 volts...probably 15 where it was when i bought the truck in 1998 my question is this.... do you think this was just a lack of charging from batteries sitting on the shelf that needed a few minutes of run time...or do you think i need my alternator checked out should i go back again things seem back to normal now.... i personally think that the new batteries were a touch low and now have come back....thoughts and thanks... .

Replies:

From : samadamsandy

does anyone know if the 1999 ram 1500 has a passenger compartment filter i keep getting a heavy sweet smell from the heating and air-conditioning as well as a yellowish dusty powder blowing out when on high. i believe it is from a heavy pollen problem we had during the summer. any help or advice is welcome. ac .

From : andy

your batteries dont need as much of a charge so it is not sending it. that is why the charging level is lower. andy original question................ i have a 1998 dodge 3500 1 ton dually cummins deisel with two batteries in it...one on each side of the truck engine compartment. i have a groggy starting truck ...it is not a battery drain or short though the night or anything...i have a lemon battery amongst the two or both may be going. this is my question....how do you determine which is the faulty battery or if they are both --------------------------------------end of original question------------------------------------------- thanks again to all that replied to that posting. i took the truck to battery depot and watched them as they did several tests on the charging system...i was told the system was charging normally...was told the alternator was throwing over 14 -15 volts to recharge the batteries.....and i always noted the volt meter on the dash was reading about the same as what they said the alternator was putting out. then they had me shut the truck off and disconnected each battery and did a load test on each...they both failed miserably....they basically cratered is what i expected one battery went to 9 volts after 38 amps was applied....so new batteries were bought 2...i restarted the truck as instructed after the new installation ........the truck fired up better than in the show room the day i bought it... ...but i look at the + and - gauge on my dash and see the battery volt meter on the dash reads below 14 volts lower than it usually had read they take a reading on the alternator and say that the alternator is now only showing 13 volts which is a concern for charging. looking at the volt meter on the dash said the same thing as the needle was lower which was basically at what the guy said...around 13 volts or so .....so they tell me to come back in a few days to see how the alternator is to see if it changes after a few days. so i go to the gym to work out and then have a 25 km drive home from the city on the highway where i see that the charging guage jumped way up and is showing well above 14 volts...probably 15 where it was when i bought the truck in 1998 my question is this.... do you think this was just a lack of charging from batteries sitting on the shelf that needed a few minutes of run time...or do you think i need my alternator checked out should i go back again things seem back to normal now.... i personally think that the new batteries were a touch low and now have come back....thoughts and thanks... .

From : tbone

while new batteries have a great deal of capacity fast cranking over old and tired ones they tend to be a little on the discharged side wet cells discharge from sitting around. then add to that the high load put on them heating up and starting the diesel in this state and they will get real hungry. peaking up two somewhat discharged high capacity batteries can put quite a load on the alternator and drop the output voltage. they should have put an inductive current meter on the alternators output wire to see the current draw when the voltage was low. the fact that the output voltage has now returned to normal after a drive indicates that is what was causing the problem and the batteries are now charged to capacity. just keep an eye on it for a while and if the voltage drops like that again have the alternator output current checked. you might also want to check the alternator output lead connections and make sure that they are clean and tight. -- if at first you dont succeed youre not cut out for skydiving original question................ i have a 1998 dodge 3500 1 ton dually cummins deisel with two batteries in it...one on each side of the truck engine compartment. i have a groggy starting truck ...it is not a battery drain or short though the night or anything...i have a lemon battery amongst the two or both may be going. this is my question....how do you determine which is the faulty battery or if they are both --------------------------------------end of original question------------------------------------------- thanks again to all that replied to that posting. i took the truck to battery depot and watched them as they did several tests on the charging system...i was told the system was charging normally...was told the alternator was throwing over 14 -15 volts to recharge the batteries.....and i always noted the volt meter on the dash was reading about the same as what they said the alternator was putting out. then they had me shut the truck off and disconnected each battery and did a load test on each...they both failed miserably....they basically cratered is what i expected one battery went to 9 volts after 38 amps was applied....so new batteries were bought 2...i restarted the truck as instructed after the new installation ........the truck fired up better than in the show room the day i bought it... ...but i look at the + and - gauge on my dash and see the battery volt meter on the dash reads below 14 volts lower than it usually had read they take a reading on the alternator and say that the alternator is now only showing 13 volts which is a concern for charging. looking at the volt meter on the dash said the same thing as the needle was lower which was basically at what the guy said...around 13 volts or so .....so they tell me to come back in a few days to see how the alternator is to see if it changes after a few days. so i go to the gym to work out and then have a 25 km drive home from the city on the highway where i see that the charging guage jumped way up and is showing well above 14 volts...probably 15 where it was when i bought the truck in 1998 my question is this.... do you think this was just a lack of charging from batteries sitting on the shelf that needed a few minutes of run time...or do you think i need my alternator checked out should i go back again things seem back to normal now.... i personally think that the new batteries were a touch low and now have come back....thoughts and thanks... .

From : otrpu

while new batteries have a great deal of capacity fast cranking over old and tired ones they tend to be a little on the discharged side wet cells discharge from sitting around. then add to that the high load put on them heating up and starting the diesel in this state and they will get real hungry. peaking up two somewhat discharged high capacity batteries can put quite a load on the alternator and drop the output voltage. they should have put an inductive current meter on the alternators output wire to see the current draw when the voltage was low. the fact that the output voltage has now returned to normal after a drive indicates that is what was causing the problem and the batteries are now charged to capacity. just keep an eye on it for a while and if the voltage drops like that again have the alternator output current checked. you might also want to check the alternator output lead connections and make sure that they are clean and tight. -- if at first you dont succeed youre not cut out for skydiving i have both ram 3500 diesel & f350 psd the later started cranking slower and having alittle trouble starting. wasnt long after this till the starter died. just another thing to check. cheers steve j. original question................ i have a 1998 dodge 3500 1 ton dually cummins deisel with two batteries in it...one on each side of the truck engine compartment. i have a groggy starting truck ...it is not a battery drain or short though the night or anything...i have a lemon battery amongst the two or both may be going. this is my question....how do you determine which is the faulty battery or if they are both --------------------------------------end of original question------------------------------------------- thanks again to all that replied to that posting. i took the truck to battery depot and watched them as they did several tests on the charging system...i was told the system was charging normally...was told the alternator was throwing over 14 -15 volts to recharge the batteries.....and i always noted the volt meter on the dash was reading about the same as what they said the alternator was putting out. then they had me shut the truck off and disconnected each battery and did a load test on each...they both failed miserably....they basically cratered is what i expected one battery went to 9 volts after 38 amps was applied....so new batteries were bought 2...i restarted the truck as instructed after the new installation ........the truck fired up better than in the show room the day i bought it... ...but i look at the + and - gauge on my dash and see the battery volt meter on the dash reads below 14 volts lower than it usually had read they take a reading on the alternator and say that the alternator is now only showing 13 volts which is a concern for charging. looking at the volt meter on the dash said the same thing as the needle was lower which was basically at what the guy said...around 13 volts or so .....so they tell me to come back in a few days to see how the alternator is to see if it changes after a few days. so i go to the gym to work out and then have a 25 km drive home from the city on the highway where i see that the charging guage jumped way up and is showing well above 14 volts...probably 15 where it was when i bought the truck in 1998 my question is this.... do you think this was just a lack of charging from batteries sitting on the shelf that needed a few minutes of run time...or do you think i need my alternator checked out should i go back again things seem back to normal now.... i personally think that the new batteries were a touch low and now have come back....thoughts and thanks... .