Gremlin in my Charging System

[SS MAYFLOAT]

Finally got my F-350 bucket truck. Diesel (7.3) runs excellent. It is not a highway truck since it only has a 3 speed auto, but it is for local use and not for the highway to cruise.<br /><br />Yesterday I noticed that when it is runnining at an idle, the volt indicator fluctuates up and down. When the rpm is brought up the battery light comes on and fluctuates with the gauge. Turned on headlights, fan, and other accesories to put a load on it. Lights fluctuate just like the guage does and does not quit. The truck has two batteries and the alternator is heavy duty 100 amp.<br /><br />To me it acts like a regulator that doesn't know what to do. I don't have a manual yet, but does anyone have any ideas what is up? Thanks.....SS

 

[OBJ]

Re: Gremlin in my Charging System

SS....got any idea of how the regulator is hooked up to the batteries? Any kind of isolator or something? But I would agree that the regulator is going south.

 

[SpinnerBait_Nut]

Re: Gremlin in my Charging System

Hang on SS, I know a man that is an expert on Ford Diesels.

 

[SS MAYFLOAT]

Re: Gremlin in my Charging System

OBJ, I'm not sure what an isolator is if it bit me in the butt. I'm new to this dual battery stuff. I'm not sure if the regulator is internal or external. Hopefully SBN's friend can help. Thanks.....SS

 

[SpinnerBait_Nut]

Re: Gremlin in my Charging System

Hey SS, what year? I'm sure he will want to know.

 

[jimchere]

Re: Gremlin in my Charging System

One thing to check before looking at the charging system as a culprit. This sounds a lot like a problem my grandfather had several years ago with is E350 van. Turns out it was a loose ground. Check the ground connections between the battery (-) and engine block, and engine block to frame.

 

[SS MAYFLOAT]

Re: Gremlin in my Charging System

It is a 94, the grounds are good, the terminals on the batteries on clean. I put my volt meter on one of the batts when it was charging. It fluctuated between 14.8 at its highest and 13.4 at the lowest. I don't want to operate it until this is figured out. Spent too much money on it, taxes and tags I know the alternator looks like it had just been replaced. The plates have no rust or dirt on them, the windings are nice a shinney, and the case still has that new finish on it compared to the other components.

 

[SpinnerBait_Nut]

Re: Gremlin in my Charging System

Is it a IDI or DI motor?<br />You know pre powerstroke or post.

 

[SS MAYFLOAT]

Re: Gremlin in my Charging System

It is not a powerstroke. It is non-turbo and I was told it was an international engine.

 

[SpinnerBait_Nut]

Re: Gremlin in my Charging System

SS, I'm still waiting to get a hold of him, but I do know that they used a internal regulator on these motors from 1993 to 1996, except '96 Super duty.

 

[SS MAYFLOAT]

Re: Gremlin in my Charging System

No problem SBN, I'm on vacation this week, I should be around the house here until about 3pm. Gonna go spend a couple of nights on der boat. Haven't been down there for the past 3 weeks, I'm starting to have fishwithdraws. But I will be back to the house each day to check on things. I'll check the posts then. Thanks for the help.<br /><br />I'll still check this post throughout today.

 

[Homerr]

Re: Gremlin in my Charging System

Your voltage sounds fine.<br /><br />If I remember corectly...<br />Take a battery reading with engine OFF.<br />Take a reading at idle (no accessories on)it shouldn't be more than 15 volts (alternator output)<br />Take another reading with heater, lights etc.. on. The reading should be about 1 to 1 1/2 above first battery reading. (Hope this is right...I know it's close )<br /><br />I have a book somewhere about this.<br /><br />This just tells you the charging is working, and sounds like it is. As far as the flickering, I would have to agree that it's a ground, bad connection, or bad harness. <br />I've had a harness go bad before. Ford made some real weak harnesses (at least they did in the 70's)<br />I call the harnesses back then 'spaghetti wire'..cause that's what it looks like! You can't run any amount of juice through them to run today's high output lighting or what-not.<br /> <br /><br />Being a 1994, who knows what *^%* computer part it may be if it isn't simple like a regulator.<br />And by the way...any Ford I've seen always had an EXTERNAL regulator. <br /><br />But then again, I've always had an older Ford.<br />(Except my new one, but it has a 10 year extended warantee...I don't get my hands dirty anymore) <br /><br />H.

 

[SpinnerBait_Nut]

Re: Gremlin in my Charging System

Homerr, acording to my chilton's '94 with 7.3 diesel had a intregal regulator.<br />Is that different than an internal?

 

[SpinnerBait_Nut]

Re: Gremlin in my Charging System

Ok SS, here is what he says.<br /><br />"It could be the alternator, the regulator or a bad connection--charging wire, battery terminals, ect; or you could have a battery that is damaged internally. If it only does it after starting, part of the problem will be the glow plugs are cycling and drawing down the charging system. <br /><br />But, the system should be able to handle the load of the glow plugs--the voltmeter will flutctuate, but the battery light should not come on. Start by having the batteries tested, check and clean all terminals, and the have alternator output tested. Full-field the alternator to see what it can put out without the regulator--disconnect the regulator and jump the harness "F" terminal to the "A" terminal. The alternator should put out 16 volts--amperage should come up, but engine speed will dictate how high."<br /><br />Hope this helps some. If not, then ask away.

 

[SS MAYFLOAT]

Re: Gremlin in my Charging System

Thanks SBN, Gonna get some hot coffee and go out and check it out, its 45 right now, not use to it being this chilly so soon. If the weather pattern doesn't change, I think we will see frost in a couple of weeks Should be a week before Halloween......SS

 

[NOSLEEP]

Re: Gremlin in my Charging System

Yes, the voltage regulator is encased in the<br />alternator as one unit. Unless its pre 1993.

 

[ebbtide176]

Re: Gremlin in my Charging System

hope you get that problem figured out SSM. i don't remember ever working on a ford with int reg. i may have, but don't remember it. so i'm not sure what to expect.<br /><br />having the alt tested should be free at an autoparts store, same for load testing batts.<br /><br />but with the batt light coming on, i'd suspect a problem with the alternator or wiring. that is if the light is wired to warn of a diode problem. maybe you can get a manual with a troublehooting chart to find out.<br /><br />do check for good connections on back of alt & feed wire from alt to batt. also, you might try tapping on the alt with a hammer handle, to see if you have a brush sticking - use voltm on batt to see if it smoothes the fluct. you can use a heavy jumper wire from BAT post on alt to batt, or jumper cables if they clamp well, without touching frame. make up some jumpers to 'replace' connections temporarily if needed. <br /><br />maybe you'll get a reply from someone more familiar with your truck/engine combo...

 

[Homerr]

Re: Gremlin in my Charging System

If it's an internal...Sound like Ford finally went import on us!<br /><br />All my older rigs have an external regulator.<br />The alternators are one heck of a lot cheaper than an internal import.<br /><br />I agree...check all the obvious stuff first before you dig into the $pendy ones.<br /><br />Good luck on finding the gremlins.<br /><br />H.

 

[Kinglg]

Re: Gremlin in my Charging System

Hey Float, why don't you try, http://www.ford-trucks.com/forums/index.php?s=db1366cb86a88b07871583c7f75afc7b <br />That's where I go when I have a problem with my <br />93 F250.