Started the beast 10 min before end of work yesterday to warm up. after I punch out I hop in and immediately notice batt light lit. Great figure I'll make it home as soon as i put her into gear and gave some throttle light shut off. stopped to eat, afterwards starts up fine no light the whole way home. fast forward this morning.
Go out fires up SLOW seemed glow plugs were on a little longer also. five seconds after starting batt light reappears, after 10 sec shuts off about a min comes back on. grab a cig lighter alt/voltage tester it is all over the place 11.1 with no throttle 14.2 under slight throttle. after warm 14.2 constant.

Here is what I've done to diagnose. 1. removes heavy wire eyelet from back of alt, cleaned reinstalled other wire plugin nice no corrosion.2. load cell tested batteries, pass.side failed replaced, driver side passed. 3. took to Oreilly's had alt tested, numbers all over the place. no alt response for 15 sec after startup than slight charge.
One last thing after 5 mile drive the alt is effing warm almost too hot to hold hand against. Sorry such a long rant just want to be thorough!!!!

 

Sounds like the internal regulator is shot. Time for a local rebuild or a replacement from a parts house.

Go back to where you bought the replacement battery for your passenger side and buy a new one for the drivers side too.

Always, always, always replace both batteries, if funds allow.

Stewart

 

With that many miles I would just get a new alternator .......for starters.

 

Funds allow however batteries are just under a year old, assuming passenger side was a fluke. was covered under mfg warranty mfg warranty will not cover the good battery still pushing 810 cca

 

Eh, if the battery was still that new, I'd do the same thing then.

Still, be safe and monitor the drivers side battery. Never know how much stress was put on it by the passenger side being bad.

Stewart

 

So the general consensus is the alternator is kaput correct. either have it rebuilt Ie replace regulator or replaced. How much does it cost usually to have one rebuilt and will it be as reliable as a reman ford alt

 

Technically, the rule is never replace half of a battery. Even flashlight makers warn of this. Could be why the alternator is toast.

 

Wait......... you had the alternator off, had it tested and it failed? and then you reinstalled it?! and you`re still trying to figure out a charging problem?

 

Lol, I should clarify the alt was still installed at oreilly's they hook up a hand held contraption to gather charging system info.

 

Update new motorcraft alternator and 2 new group 65 880 cca interstate batteries installed. charging good and steady!
One final question is there suppose to be a delay perhaps from after start glow plugging from time between startup and when alt begins to charge seems to be still a 15sec delay. after about 15 seconds jumps right up to 14.2 volts. anyone ever done a realtime startup voltage check?

 

I am on my third alternator for a 2005 6.0. It ( the alternator ) always seems to go caput when I am in the middle of nowhere on a holiday weekend and what I end up with because it is all I can find is an overpriced Ford remanufactured unit. Both times I have replaced mine have been at a national forest campground.

Will be researching a quality aftermarket unit when it warms up around here.

 

It seems like diesels go through them faster, maybe something to do with the 2 batteries.

 

which PSD motor do you have?

on the 6.0, the glow plugs continue to stay energized for almost a minute at times after starting.

so yeah, it's normal for the voltage to be low at first. then suddenly jump to 14 volts. really freaked me out on my old 6.0 until I was reading about the PSD charging system inthe 6.0 section here on FTE.

 

Are any of you guys having any sort of other odd electrical issues? Perhaps an odd stumble here or there, low power rarely or even a random dead pedal? My old mans 6.oh was eating alternators and Boyer found a chaffed main engineharness under the hood replaced that sucker and he has been good

 

Yes, the charging system delay is normal. the field is controlled by the computer, it waits and then ramps up to start charging....diesel or gas.