99.5 Powerstroke.

My alternator quit on me and by the time I finally got home and got done trouble shooting it the batteries are down to 11.6volts. Not enough to turn the truck over to start it. Im going to brave the snow in the AM to get a new Alternator. I dont have a battery charger, should I charge the batteries off my wifes Honda Civic? Or is a drain of 11.6 volts not to bad and myabe I could just jump it after I get the new alt in?

thanks!

 

the 7.3's have to turn over pretty good to start,i think about 1200 rpm(optimum).ma's little honda will have to run quite a while to get the duallys up worth a try,but don't be impatient let the honda run quite awhile before you try to stsrt it and plug in the block heater and let it get the motor warm.or you can cheat a little ,like i did.they say don't use starting fluid in the modern motors but i have done it quite a few times with good results.i drilled a small hole in the air fiter and spray just a little bit of ether in the motor,then start cranking right away,before the glow glow plugs have a chance to heat up.good luck

 

A cheap battery charger is $30.

Why do you want to risk, bud?

 

Do they work any good? I'd spend $30 on a battery charger. Unfortunately we have a blizzard for the next two days here, forecasts of up to 2ft of snow. Its coming down pretty good. Wish I had a Garage!

 

A $30 charger that does 10amp hour output will fully charge your 2 batteries in about 24 hours.

If you got the time, you are better off to use that, rather than the high amp quick charge cycles that damages the batteries.

 

I would use a battery charger. Alternators are not designed to charge a dead battery like that. I want to say I spent around $50 on my Schumacher 2/15/100 charger.

 

Will the larger case alternator from say a 96 bolt up? I got a truck out back I could rob it and the pigtail out of.

 

I am not sure.

The alternator ratings are deceptively small from Ford.

e.g. 110a for my diesel.

But in fact, they are rated for close to 100a at 90 to 100% duty cycle (ford keeps the specs close to their vest, so we have to guess).


No car grade alternator can do close to what the Ford OEM alternator does continuously unless it is way bigger rated... e.g. 200a

So your choice:

a) get Ford OEM PN (not even a "also fit" but an exact PN)

That works for factory loads, no add on loads

b) get a heavy duty aftermarket $$$

That is like a $300 or more part.

Your $100 autozone alternator will last about a year, and will likely take out your batteries on the way to saving you a few dollars.

On the 7.3... the starter is a 3.5kw unit... I think.


Think twice before putting a sub-standard alternator on it.

I would go Ford OEM reman if you want to save.

 

Not sure were your from but any Autozone will charge and test your batteries for free....All you have to do is ask...

 

Another option is to have your alternator rebuilt... And most places can even increase the output... for considerably less than new/reman... If your in ma.. Call Hub alternator in Malden... Guy does top shelf work and is very resonable...

 

If you go that route --- be sure you tell them it is a diesel spec alternator with a very heavy "duty cycle" load.

I tend to like dealing with rebuilders who I can stare back at when their product failed...

That is how I ended up with a custom alternator.

Technically only rated for 145a

But it can pull that in the heat of summer, all day, all night.

No bragging rights with people rated with 200a alternators, until they discover that their continuous rating is around 70 amp... and they have a dead alternator.


BTW, alternators sell quality by weight ---- it is impossible to make a light one and make it strong / high rated.

Weigh the autozone one against a real alternator (eg. a Mitsubishi ambulance alternator).. that monster is about 3 to 4 times the weight of the cheapo.

 

So my brother came over last night and in about 10 min we put in he alternator he had. we put the battery on 2amp charge and the truck fired right up a little later. We left it on 2amp overnight. So all is good for now. I will probably bring my alt. in for a rebuild to have it on hand.

Thank guys!

 

Glad everything worked out, sometimes things can seem worse than they really are. It's a bummer having to do it in a snow storm but that is usually the way it happens. If the one you and your brother put on is used I would seek out a re-builder for sure and have a backup waiting, maybe even change it over when the weather permits.

 

2ah charger works good, when you have the time.

Just charge it all week overnite.