Notices
Like Tree7Likes

f250 dead short

Old 07-30-2018, 07:09 AM
  #1  
Senior MemberCaptains Club Member
Thread Starter
 
Join Date: Dec 2003
Location: Northern Neck, VA
Posts: 5,385
Default f250 dead short

02 diesel, 230,000 miles
runs great

only use once every 3 months or so. starts every time
batteries were 3 years old or so.
left all four doors open packing for vaca, wanted to bring kayaks and paddle board, wouldn't start- i assume bone headed dome lights killed the old batteries. It wouldn't have if they were normal/strong

jumped it off my car and drove 4 hours to OBX no issues.
the next day i went to start- dead. figured i killed the older batteries. ran to auto zone. bought and installed w new batteries.
all good right? no!

batteries were dead 2 days later. Jumped off relatives vehicle. Starts right up- so not starter, not batteries
Alternator?? naw, no idiot light on and after i jumped it again it ran 4 hours home fine.

disconnected both batteries in my driveway as soon as i got home so i will see if it starts tonight.


then i have a short right?
where and how to start looking?? pull fuses one at time?
rocksandblues is offline  
Old 07-30-2018, 07:12 AM
  #2  
Senior MemberCaptains Club MemberPLEDGER
 
Join Date: Jan 2005
Location: SC
Posts: 10,391
Default

Likely the alternator rectifier has died. Alternator is undersized to start with. With the motor cold, put a charger on the batteries. Alternator will likely feel warm to the touch after a while. If it does, that's your problem. Could still be the problem regardless whether it feels warm or not. If you are still on the stock alternator, you are beyond due anyway.
autobaun70 is offline  
Old 07-30-2018, 09:31 AM
  #3  
Member
 
Join Date: Oct 2017
Location: Middle River MD
Posts: 86
Default

first check to ensure the alternator is charging properly. using a DVOM or voltmeter red lead to positive and black lead to negative should have 13.5 to 14.0 volts
If the alternator is charging you could have a battery draw, in which case you would need to do a battery draw test to see if you in fact do have a draw. fords spec is anything greater than 50Ma (milliamp) a quick search on google or youtube can show you how to do a draw test.
UPPERbaycrabNfish is offline  
Old 07-30-2018, 09:32 AM
  #4  
Senior MemberCaptains Club Member
Thread Starter
 
Join Date: Dec 2003
Location: Northern Neck, VA
Posts: 5,385
Default

it is a 3 year old alternator- car quest. not the original
maybe shorted the rectifier out when jumping?


so with batteries connected and charge and truck not on- feel alternator?

Have multimeter- will try testing tonight...
UPPERbaycrabNfish likes this.
rocksandblues is offline  
Old 07-30-2018, 10:09 AM
  #5  
Senior MemberCaptains Club MemberPLEDGER
 
Join Date: Jan 2005
Location: SC
Posts: 10,391
Default

Originally Posted by rocksandblues View Post
it is a 3 year old alternator- car quest. not the original
maybe shorted the rectifier out when jumping?


so with batteries connected and charge and truck not on- feel alternator?

Have multimeter- will try testing tonight...
Correct, but wait 30 minutes or so before checking. Will take a bit for it to warm up.

Jumping won't short the alternator, but it trying to bring up a pair of big ass batteries from dead can overheat it and cause it to fail. Honestly it is a bad setup. Given the capacity of that battery set, a higher output unit would be much better. Stock is only 105 or 110 amps I believe. Essentially it runs at full available output until the batteries come up, and just can't dissipate the heat that is created by doing so, especially in hot weather. If the truck sits a lot, I would definitely keep it on a battery tender. My brother drives the same truck, and we modified 160 amp to go on it off a later model Ford. Even though your batteries are only 3 years old, if they have done a lot of sitting without being on a maintainer, very good chance one or both of them is shot. If so, replace in pairs, never just a single unless there is no other option to get you home.

Depending on which specific diodes failed, there is a chance it can still be putting out 14 volts give or take when running, and kill the battery when resting. Putting your hand on it with everything cool, and the charger hooked up will indicate that it has failed in one particular manner, but a lack of heat doesn't mean that it is good. I would pop it off and take it to the closest Advance (bought out Car Quest) location. They may be able to track down the purchase, but otherwise you will need a receipt for them to honor the warranty. If you can track down a mom and pop shop, they should be able to fix it pretty quick and for a lot less than a new one.

Last edited by autobaun70; 07-30-2018 at 10:33 AM.
autobaun70 is offline  
Old 07-30-2018, 10:32 AM
  #6  
Senior MemberCaptains Club Member
Thread Starter
 
Join Date: Dec 2003
Location: Northern Neck, VA
Posts: 5,385
Default

thx much! will update
rocksandblues is offline  
Old 07-30-2018, 10:35 AM
  #7  
Senior Member
 
Join Date: Sep 2011
Location: Wilmington NC
Posts: 329
Default

Forget about feeling the alternator and all this bad advice.

You need to see if the truck is charging or not , using a multimeter or just the gauge on dash. The battery light would probably come on the dash if it wasn't charging, doesn't matter how old the alternator is. They go bad.

Sounds like to me you have something drawing quite a bit of power when the truck isnt running. If the alternator wasn't charging you for sure wouldn;t have made it 2 hour drive on a jump start
simeoncoleman likes this.
dirtymike72 is offline  
Old 07-30-2018, 10:52 AM
  #8  
Senior MemberCaptains Club MemberPLEDGER
 
Join Date: Jan 2005
Location: SC
Posts: 10,391
Default

Originally Posted by dirtymike72 View Post
Forget about feeling the alternator and all this bad advice.

You need to see if the truck is charging or not , using a multimeter or just the gauge on dash. The battery light would probably come on the dash if it wasn't charging, doesn't matter how old the alternator is. They go bad.

Sounds like to me you have something drawing quite a bit of power when the truck isnt running. If the alternator wasn't charging you for sure wouldn;t have made it 2 hour drive on a jump start
The alternator itself is likely the draw. If it is hot, when everything else under the hood is not, it is a dead give away. No, that's not the standard test for an alternator, but in this case, it is a perfectly valid diagnosis method. When one fails in this manner, it can in some cases still charge the batteries when running, and kill the battery when not. When an alternator fails in the manner that his likely has, the diodes burn closed, which allows power to flow to the windings of the alternator when the key is off. This turns those windings essentially into an inductive heater, which will quickly kill a battery or batteries. This is especially likely to occur in very hot weather, and on vehicles that sit a lot without being on a battery maintainer. He has both scenarios working against him. Especially this specific charging system, which is a bad design to begin with. From the factory they are putting out all they can (110 amps). Units that were used for commercial service were typically fitted with a second 110 amp alternator to make running extra lights, accessories, etc. possible.

BTW, I remanufacture alternators for a living.....and my brother who also works in the business drives the exact same truck. Very familiar with the shortcomings of its charging system.
autobaun70 is offline  
Old 07-30-2018, 02:25 PM
  #9  
Senior MemberCaptains Club Member
Thread Starter
 
Join Date: Dec 2003
Location: Northern Neck, VA
Posts: 5,385
Default

Update:
hooked batteries up. Charge held perfectly
waited 30mins.

Alternator never felt warm. Bolts had dropped to 11.8 from 12.2 in just 30 mins

started it. Watched the vokts climb right back up

now disconnected again.

Assume alternator?
bench test?

disconnect alternator leads and reconnect to see if that’s consuming juice??
rocksandblues is offline  
Old 07-30-2018, 02:34 PM
  #10  
Senior MemberCaptains Club MemberPLEDGER
 
Join Date: Jan 2005
Location: SC
Posts: 10,391
Default

Sounds like it. 30 min may not have been enough for the heat to be noticeable. You can pull the battery terminal wire from the back of the alternator, as well as the plug from the regulator and see if the issue goes away overnight. The battery terminal wire is constant hot. If you pull it, insulate it well while it is unhooked, and have your negative cables unhooked while you do this to prevent any accident arching from your tools, then hook back up your battery cables. As easy as they are to get off, I would pull it and get it bench tested at this point. Definitely charge the batteries up and have them tested as well. If it is bad, make sure they give you a unit that crosses to Lester 8316, and specifically not Lester 7796. They look the same, hook up the same, but are not the same. One has Avalanche diodes, the other does not, and won't work.

This is a partial list of compatible part #'s.PM me an email address and I can send you a cleaner version, bunches all up when pasted into a thread.

WAI New8316NWAI Old1-2511-11FD, 1-2511-11FD-2WAI Reman Premium Quality8316RACE ZorkosCA8316NAlltech306-8316American Power SystemsAPS8316Armature G Roy8316Atelier DynamoA8316Auto Electric Suppliers8316NBeck Arnley Remanufactured186-6453Bepco80-8316Bosch RemanufacturedAL7610XBosch Service Europe0 986 042 650CPIKITDuBois908316, R908316EGIA-8316Elpar Industries021603648Excel8478Ford2C3U-10300-BB, 2C3U-10300-BC, 2C3Z-10346-BA, 2C3Z-10346-BARM, 2C3Z-10346-BB, 2C3Z-10V346-BBRM, 4U2Z-10V346-CARMFord Engineering2C3U-BB, 2C3U-BCHella8EL 011 710-591, 8EL 737 930-001Hollander961Lester8316Metron8316Metron USAD-8316Minnpar47-1997Minnpar Old6881997Mondial60-524-60Mondial New60-524-60NMotorcraftGL-530, GL-625, GLV-8658-RM, NGL8316NNastra8316Nastra New898316Nastra VelocityE8316New Generation503116New TechN8316New Tech HON8316HOOur Part Number8316N, 8316RPart #8316PASCOA-600426Power Select8316N, 8316RPowerite Automotive8316Precision Parts & RemanufacturingFOA149PTSN8316Quality Rebuilders8316Raw Power8316N, 8316RRayloc133160Rayloc New1N3160Real20150031Reliance7897Remy New92526, 92569Remy Remanufactured23747, 23811, P8485, P8552Road Warrior8316N, 8316RRotex8316Stratoline80-8316Suncoast8316Techno CVCAME-8316TSA8316NUCP New8316NUCP Remanufactured8316Ultima Select392569

Last edited by autobaun70; 07-30-2018 at 02:41 PM.
autobaun70 is offline  
Old 07-30-2018, 02:48 PM
  #11  
Admirals Club Admiral's Club Member
 
Join Date: Feb 2015
Posts: 654
Default

Highly doubt its the alternator, most likely you have a parasitic draw, google parasitic draw, its a lot easier than trying to explain threw trying , but your on the correct path, with pulling the fuses, i just had a f250 doing a similar thing it was the electric clutch fan. I unplugged it and short was gone. good luck these type of fixes take patience and are a pain in the butt
aquaholic23 is offline  
Old 07-30-2018, 06:12 PM
  #12  
Member
 
Join Date: Oct 2017
Location: Middle River MD
Posts: 86
Default

Do a parasitic draw test and see how many Miliamps your drawing. Like I said before 50MA and below is good. I suspect you will be way above that.

Once you find you do have a draw you can start pulling fuses one at a time. Be careful Some fuses that feed modules will “wake up” that module and you will have to start all over again. I suggest starting with the most likely radio and such. Also to rule out the alternator you can unplug the three pin connector and the battery cable at alternator.
UPPERbaycrabNfish is offline  
Old 07-30-2018, 06:17 PM
  #13  
Senior MemberCaptains Club Member
Thread Starter
 
Join Date: Dec 2003
Location: Northern Neck, VA
Posts: 5,385
Default

Was the alternator.

Pulled wires from alt, reconnected batteries and volts did not move for several hours

pulled records and it was a car quest alternator from early 2017. They gave me a new one in exchange. Put new one on and all better now

thx


thx
rocksandblues is offline  
Old 07-30-2018, 07:22 PM
  #14  
Senior MemberCaptains Club Member

 
Join Date: Nov 2003
Location: Wanchese, NC
Posts: 10,589
Default

I had a issue like this and it was simply a slightly corroded battery lug. Cleaned all the battery lugs and battery posts. No more issues. My 7.3 is super sensitive to even the slightest corrosion between the lugs and battery posts. I now clean them really good once a year.
offshore3144 is offline  
Old 07-31-2018, 05:15 AM
  #15  
Senior MemberCaptains Club MemberPLEDGER
 
Join Date: Jan 2005
Location: SC
Posts: 10,391
Default

Originally Posted by rocksandblues View Post
Was the alternator.

Pulled wires from alt, reconnected batteries and volts did not move for several hours

pulled records and it was a car quest alternator from early 2017. They gave me a new one in exchange. Put new one on and all better now

thx


thx
Definitely get your batteries tested soon, and if possible keep them on a battery tender when the truck is sitting.
autobaun70 is offline  
Old 07-31-2018, 05:56 AM
  #16  
Senior MemberCaptains Club Member
Thread Starter
 
Join Date: Dec 2003
Location: Northern Neck, VA
Posts: 5,385
Default

Originally Posted by autobaun70 View Post
Definitely get your batteries tested soon, and if possible keep them on a battery tender when the truck is sitting.
Batteries are 5 days old. That's what I thought it was at first.
But thanks for your earlier help

Truck sits 3 months at a time for probably last 5-7 years. Has not been a daily driver for that long. The batteries, so far, have held up fine over the years with out a tender. I am sure you are correct that a tender would prolong their life over 3-4 years but I store it on a piece of property I own that does not have an easy power outlet.
rocksandblues is offline  
Old 08-02-2018, 11:18 AM
  #17  
Senior MemberCaptains Club Member
Thread Starter
 
Join Date: Dec 2003
Location: Northern Neck, VA
Posts: 5,385
Default

batteries dead today for son wanting to use
;(

dont know why batteries voltage held fine for 4 hours while altenator ws disc.

guess i am pulling fuses
rocksandblues is offline  
Old 08-08-2018, 03:48 PM
  #18  
Admirals Club Admiral's Club Member
 
Join Date: Jul 2012
Location: Palm City, Florida
Posts: 816
Default

FWIW, my 02 developed an internal short in the factory stereo head unit. Same symptom. May be a good fuse to pull to check.
Track Junkie is offline  
Old 08-09-2018, 07:37 AM
  #19  
Senior MemberCaptains Club Member
Thread Starter
 
Join Date: Dec 2003
Location: Northern Neck, VA
Posts: 5,385
Default

Thx
yeah. The stereo is the first one I am going to check
it has a high end DVD player/stereo with 3 amps and custom box behind rear seat. Was fun back in the day. Will blow clothes off in the back seat.

First cicuit i thought of


on vaca all this week. Fully expect it to be dead in driveway again. Will dig into it next week
rocksandblues is offline  
Old 08-10-2018, 12:34 PM
  #20  
Senior Member
 
Join Date: Nov 2008
Posts: 1,044
Default

When I read the title, I thought of this problem, also a 02 7.3 that developed a dead short for the entire truck. It would happen randomly and without warning. In my case a jump wouldn't help anything, as it always restarted as if nothing had happened. Sometimes it was like the batteries were dead, but they weren't, or it would die while driving, lights included. Long story and many headaches later, it turned out to be a connection on the drivers side fender. The battery cable goes to a stud, and another identicle cable goes from the stud to the power supply. Not all of these trucks have this connection. No idea why some have it and some don't, but if yours does, inspect it for corrosion.
I Fish 2 is offline  

Thread Tools
Search this Thread