1997 F250XLT PS 4x4 Crew Cab. Original owner bought in fall of '96

Battery light is on Ammeter will not go above "N" in "normal".

I pulled the alternator and had advance auto test on their tester and it passed.

Pulled both batteries and trickle charged.

Starts and runs fine as long as I remember to pull the batteries after a while and trickle charge.

On a guess I replaced the fender relay. That always fixed this kind of issue on my past gas powered ford trucks and cars.But, it didn't help with this no charge problem at all.

History: Only known major issue I've had is a glow plug system problem. Wait light seems to come on then go off as it always did when new but now truck never starts on cold days unless I load it up with starter fluid. After it starts the ammeter is on the "N", then after a while rises up to the "M" and I can tell I have full voltage power to the truck systems. I have changed the glow plug relay in the past (year 2000ish) to fix this particular issue but it didn't fix it at all. So purchased all new glow plugs, then found out they are under the valve covers, so put the new glow plugs in a tool box drawer and have been using starter fluid in the cold-cold days of winter. After the engine is warm, subsequent starts are ok and do not require starter fluid unless I shut it down so long that the engine cools back down.

Another issue was a dragging starter some years ago. Replaced both batteries and still dragged on start. I happened to be working a contract in Charl SC at the time so on a tip from my brother took the starter to some marine repair place where they said they rewound totally rebuilt my starter.They warned me to stay away from rebuilt starters from some auto parts outlets as they wouldn't hold up as well as the orig starter so long as its properly rebuilt. Anyways, theres never-ever been a starter issue with my truck since then.

Is there a such thing as a glow plug relay going bad in such a way that it prevents the alternator from outputting voltage? Could it be my after market gpr I changed "way back when" went bad on me causing this no-charge problem?

I'm on a limited retirement income now and just my buying the fender relay was difficult.

I did some tests that seemed to pass as posted by paladin921 regarding his own no-charge issues. Unless I bungled his testing procedures; my charge system tests ok.

confused and out of ideas, jimb

wanted to add that I do not have a wiring diagram for my truck.The books I did have, I can't find anymore. I do have my psm37 multimeter and schumaker charger.

 

Your charging system may be ok but what about the batteries...no mention about when they were last replaced. Pull them and take them where the alternator was tested. ask them to do a load test. I'd suspect their replacement is overdue.

Best to replace both at the same time...may be tough on retirement income but that is really the best approach.

 

It's always possible with a bad GPR he's getting a drain while its sitting.

just a wise *** guess though.

 

Sure, its possible, especially if it's contacts have seen a rough life. A little carbon and a little contact splatter makes for a conductive path.

Best approach would be to thoroughly troubleshoot the electrical system...kinda tough with just a multi-meter (not impossible, just tough).

 

with the multimeter, check voltage at the batteries with engine off, and then check again with engine running.
engine off voltage should be approxamatly 12.5 volts.
with engine running, the voltage should be between 13.5 and 14.5 volts if the charging stystem is working properly.
once we know what the battery voltage is running and not running, we can go from there

 

Please don't use "Starter Fluid". I don't get why people always insist upon using ether and other starting aids. It clearly doesn't fix the problem, it only alleviates the symptom, which is a no start condition, temporarily.

Okay, on to your problem. I read that you pulled your alternator and had it tested and that it passed. Also, you pull the batteries regularly to charge them. You ought to take them to the same place where you tested your alternator at some point, since you're going to pull them anyway. That will tell you something and get you somewhere.

 

These batteries I bought both at the same time in 2006 from autozone.They are durallast gold:

Just got back from advance auto. I happened to be half way through a trickle charge routine when I saw the post to get the batteries tested. The battery on the pass side was full trickle charge when I installed it. I pulled the drivers side off the charger early and installed to drive to advance auto for the test. (It had been charging for about 3 hours).
They tested both batteries. Here is what the print out has on it from their tester:

Drivers side(the one I pulled off 3 hour trickle charge)
"Results
Charge Required
voltage: 12.39v
Measured: 455 cca
Rated: 875 cca
Temperature: 83 deg F

Battery charge is low and must be charged to determine condition."

Passenger side (trickle charged complete)
"Results
Good - Recharge
voltage: 12.53v
Measured: 702 cca
Rated: 875 cca
Temperature 89 deg F

Battery is good but low on charge. Charge battery and return to vehicle."

So I guess I nullified the whole battery test by pulling that one battery off the trickle charge to soon to get the test done.

But lets say that drivers side battery is absolutely bad, will that stop the alternator from voltage output?

Results of checking battery voltage engine off and on:

Eng off:
Pass side: 12.48vdc

Drivers Side; I removed Pass side only neg first: 12.44vdc
Drivers Side; I removed Pass side neg and pos first: 12.42vdc

Eng running and all battery clamps are connected:
Pass side: 12.33vdc
Drivers Side: 12.33vdc

Alternator big wire in back:
Engine is running, all battery clamps are on: 12.29vdc

Battery lite was on throughout the running tests. Ammeter needle did not move up
from the "N".

Shutoff engine. Disconnected completely the drivers side battery. Eng started up fine. Battery lite stayed on. Ammeter needle did not move up from the "N".

As for starting fluid. I just can't get up in there anymore to pull valve covers.
Especially the line of work I was once in always on the road. Wasn't able to do it
physically then and surely can't now. So for that winter cold start thing; I'm stuck
with starter fluid, well unless I win a lotto or something. I have changed glow plugs before, but they were on utility buckets, older diesels. Thats why, cost aside, I went ahead and bought those new glow plugs and wrongfully thought I'd just "change them real quick. "

jimb

 

Where abouts you located. Might be someone could give you a hand with this truck. Stay off that ether. I have seen diesels get addicted and not start in July with out it. You Said Battery light on, if it's on while running there is a problem like bad diode I think. Battery light is supposed to come on during WTS and go out when running. I have little confidence in Adxxxx or Auto Zxxx parts or the ability of many of their employees to check anything.

 

Wiggle the connector on top of the alternator. It is know to get loose and cause your symptoms.
Hot glow plugs + ether = big explosion = bent connecting rods!
If you must use ether be sure to disconnect the Glow plug relay to avoid engine damage.

 

battery voltage and alternator output voltage with engine running tell us the alternator is not working.
now there could be two reasons for that.
either A: the alternator field is not getting energized, or
B: the alternator is no good.

as Cuda Jim suggested, try wiggling the connector on the alternator and see if you get over 13.5 volts to the batteries.

 

Here is the diagram for the circuit in question

 

Hello everyone,
I wanted to thank you all for your support. You all are great wonderful folks.

I wanted to let everyone know that it was the alternator. I took it to an Autozone yesterday and the fella found it outputting "0" volts. The Advanceauto guy on the 1st test back in early July had bench-checked the alt and said it was good and the driverside batt failed the battery test. The pass side batt passed the batt test.

I ended up buying a Autozone reman alt (cost 140.00) and 1 batt; they prorated the battery (cost 43.00. I had bought 2 new ones from them in '06(?)).

I'll get the other new batt mid Aug hopefully. My trucks putting out good strong voltage now and the ammeter is up where its supposed to be. Hopefully the reman alt is a good one and has a long life.

I'm sorry to say the glow plugs will have to wait till maybe Sept.

Thank you so much for the wiring diagram. Very-very helpful "shooting the wires".

You all take care,

jimb

(driving to Warsaw, VA tomorrow in the a.m. so should be a good test)