Yes, I put DCpower repaired the 250XP on their dime and I stuck it back on. As for wiring I did the Big 3. Something similar to this but with more wire. 1/0 I think. 3. Upgrade your alternator wiring.

 

I cannot argue with the math. I will clean up the connections to the frame. I will replace the rear battery ground cable from the battery with a brand new cable. The vans have weird cables. The positive is 1 large cable with lots of tentacles. I cannot remember what the ground cable looks like.

My wife got a big laugh out of your response. She wants to know how people have time to respond with such detail and asked if I understood. I do understand. However, I don't have the experience or knowledge to write such a detailed post with the math to back up it up.

I explained to her that many of the super posters are smart and experienced. She then asked how much these people are paid to post. To the best of my knowledge, I told her "nada".

Thanks for the details and images of the cables. One of the best posts I have read on cable conductivity.

 

Y2K, you will believe this. I got off the phone with Quick Start, a small alternator manufacturing shop in Michigan. I asked the guy about grounding the alternator to the frame and he insisted I run a 4 gauge cable from the alternator to the rear battery. Says the frame is not a good conductor.

I am going with the frame!

 

At least you were able to reach Mr "Quicktifier" and confirm that he exists. He never answered the phone, nor did he return messages, when I called.

Then again, the Caller ID that is attached to my phone number must broadcast something to the effect of "Asks arcane questions, avoid at all costs", so I've become somewhat accustomed to the silent treatment.

Did they suggest 4 gauge positive cable too? Or just 4 gauge negative cable as we have been discussing for the last few posts of this thread? As you can see from the chart above, 4 gauge cable has 93 times LESS Cross Sectional Area then your van's frame.

And a 4 gauge positive cable might also be a little light for the long distance I am imagining you are running to your third battery, although I don't know the particulars of your install.

I do know a particular about the van frame though...


Unlike the pickup frame, that has the separate front serviceable frame section that is riveted to a factory splice insert that enables the majority of the frame to be saved and only the front section replaced in a head on collision... the van frame is continuous, and doesn't have that splice.

Also, the front boxed section of the van frame extends further aft than the pickup, which in effect increases the cross sectional area substantially, but this increase is ignored because we are only considering that part of the frame between batteries where the cross sectional area is smallest.

And that is the essence of the very valid point that TooManyToys was making... to any extent that a two part frame is joined with fasteners or is otherwise non contiguous, there can potentially be a decrease in the conductivity value of the frame. But this isn't the case with the van.

Notwithstanding, Jack's first point about bolted connections is worth paying attention to, even if the frame had the cross sectional area of the hull of the Titanic. The weakest link limitation prevails here, so no matter how you run your grounds, the importance of good, solid, tight, corrosion free, biting metal to metal contact at cable connection points cannot be over emphasized.

When bolting big ground bolts through the frame, some folks get the idea to use LocTite to make sure that the bolts don't back out. Bad idea, because the LocTite wicking around the helix of the threads can become an insulator. Again, the OEM's provide the best example to follow, because while the OEM's sell bolts pre embedded with thread locking sealant for use throughout many frame attachments, the OEMs do not use thread locking compound on grounding bolts.

Most often, OEMs use self tapping bolts for interference fit thread engagement through the frame for grounding bolts, coupled with star locking washers. There are star washers that have raised tines on both the inside and outside circumference of the washer, for double bite into the frame. Current can thus flow through the thread to thread contact, as well as through the head and nut flange to star washer biting engagement.

Perhaps the most important safety concern with remote frame mounting batteries is protecting the positive cable from dead shorting to the frame, especially in a collision or when running over something on the highway. I'd spend some money on positive battery cable protection for those unlikely events.

 

I am so happy to see this thread. I was contemplating about doing a remote battery setup so that I have room for remote oil filter and bypass oil filter (just rough thinking, not sure if it's the best location). Wow, I have to edit this, because I was so happy that I re-read and this is not about remote battery setup, but about alternators :-)

I think the frame metal is just too big compared to the copper cable even with steel having much less conducting capability compared to copper.

So as many pointed out, the bolt is the one. I would put a large copper washes there. One on the shiny frame and another copper or steel washer clamping the cable.

For remote battery setup of the econo van, the negative of the battery goes to the frame. I don't remember if there is another negative cable to the front or not. Maybe yes.

I have a remote battery holders from the econovan, but it's a pain to remove with the weight of the batteries. So I plan if I do that mod, I would make sure to weld up something that I can remove the battery without removing the whole battery box.

Anyway, I think that heat is what kills alternator, or at least a major factor. Did anyone tried with using heat insulator washer, such as using pre-made or made one up from material like exhaust wrapper to make sure engine heat doesn't transfer into the alternator?

I think even teflon washer would be enough for the temp, but it's plasticity may not be good for the alternator washer. But that's just a guess. Also, it needs to be not too thick or things can be out of alignment. It's a lucky thing that for 6.0, the alignment is not messed up. Some other alternator configuration would push it side way versus the belt.

 

If I do my three batteries on the frame, the frame will not be used. This part of the county sees way too many assaults on the conductivity of even one extra bolted connection for my goals. I may only do one battery on the frame, that too will go copper to the motor. If the PC-1750 batteries are still available at a real good price as noted recently, all that frame work may not happen at all.

Thermal conductivity from the motor, through the intake manifold and to the alternator case is the least thermal situation I would be concerned of.

 

Yes, thanks for pointing it out, the intake has 2 gaskets that are probably good as thermal insulator. The small long legs holding the alternator in this case also help alot in not sending too much heat.

On another hand, I wonder if someone add a capacitor bank to the current batteries to improve the "first" boost and also to balance out any charging spike (if any).

How about any mod to have a separate circuit for the truck as regulated 12V just to the ficm is happy.
Or even just cut off the power line of the FICM, and put it in with something like this:


Assuming over simplifying of the FICM connections.

 

Most of the heat is generated within, depending on design and load. Secondarily is the thermally charged air from cooling the radiator and just captured by the hood.

But it depends on the load.... and the cooling capability of the alternator.

October 17, 2015 4:30pm after a return home trip of 45 miles.

 

Both of these proposed washer ideas would likely invite more problems than they would seem to solve.

Copper washers snuggled up to a bright shiny steel frame will do more harm than good, because with the frame wax or electro deposition coated corrosion protection cleaned off the steel frame to make it bright and shiny, the more nobler copper washer will have unfettered access to the annodic steel. You will have a fourth battery, albeit a single cell battery, not capable of producing useful voltage, but certainly capable of generating electrolytic corrosion between the dissimilar metals, rapidly corroding the less noble steel, especially when exposed to dissolved oxygen, such as when driving through the rain.

Teflon washers, or washers made of some type of exhaust wrap, which is often woven with fiberglass matting at it's core... both of which are non conductive materials... would do exactly that: Not conduct the necessary grounding to the block that the alternator case relies on in the OEM configuration. That wouldn't be good.

 

Awesome response. Yes, for this case, the alternator doesn't need thermal insulator. And as you pointed out, more complexity, such as running separate negative wire versus using the legs.

On the frame with copper washer, I understand, but overlooked that fact (where hot water heater tank needs anode rod). With the econo van, the battery cable's terminal attaches directly to the frame I think. I don't know what they coat them with. But I often clean the steel surface shiny and then use some di-electric spray. I know dielectric don't help conductivity. However, as my understanding goes, the high pressure of the bolt will send electric over, while the dielectric prevent corrosion goes into the gap. But just want to say how I guess it would work, not really saying that's how they should work.

I am all ear!

 

Yes, in the E-Series frame mounted remote battery installations, Ford attaches the negative battery post directly to the frame. This is one reason why I suggested that coolfeet do the same.




As for what Ford coats the battery cable that attaches to the frame with, I don't know what the chemical constituents of the coating material is either. We could say tin plated, as it looks silvery, but it could very well be something else that Ford found equally effective at mitigating corrosion. Clearly, by the silver color, it isn't bare copper.




Speaking of being "all ears", notice the little ear on the Ford factory negative battery lead that bolts to the frame. It corresponds with a smaller satellite hole very near the hole through which the negative eyelet bolt is attached to the frame, and the little ear tucks inside the smaller hole as an anti rotation pawl, to prevent the weight of the copper lead from screw jacking the bolt loose when the vehicle is jiggling down the road. I would copy the OEM in this regard as well.

Finally, I wouldn't put ANY holes in the horizontal frame flanges. I'd only put holes in the vertical frame web, which is the more stress neutral part of the frame, where any holes added will not weaken the frame, nor will any bites from star washers create crack initiation sites in the frame. Another case where the vehicle manufacturer sets an example of what works, without the gotchas that some otherwise admirably creative thinking might lead to.

 

Adding an anti-rotation tab on to a commercial lug eyelet isn't going to be that easy to the average person, but you can add a cable clamp close to the connection that's bolted to the frame to achieve the same anti-rotational goal.

 

Interesting you mention the little ear on the Ford factory negative battery lead that bolts to the frame. Last summer while traveling deep into British Columbia on a Saturday afternoon, I noticed the engine starting hard. I crawled under the van and discovered the bolt with the ear was loose. I tightened the bolt and was able to start the vehicle. The battery bank more than likely was low. I found an outlet for connecting my battery charger.

Thanks for this amazing information! You got me laughing about Mr. Quick Start too. I was surprised he picked up the phone. Sounds like he still uses a microcassette answering machine.

 

Had you ever worked on that connection before? Was it the stock self threaded bolt into the frame? Did you do anything else other then retighten?

 

A dual alternator system can put out a combined 250+ amps, and the E-series is already wired for dual alts. The only difference is the dual has a positive cable from B+ of the lower alt to the battery junction box, Based on that, the stock config should have no trouble handling a high amp single alternator as long as a second positive cable (with fusible links) is added from the B+ to the battery junction box. This is the path I took when I upgraded to a 200 amp Denso and it worked fine.

Also, next time I get down to the alternator I'm considering leaving the stator out when it goes back together. Pulling the radiator, to pull the stator, to pull the alternator is a big job and ruins most of a day at home with plenty of tools. It would be next to impossible if broke down on the side of the road. Without the stator it would be a 1 hour job and I wouldn't worry about putting in a cheap reman from the local auto parts store if that saved a vacation and got the truck home. Or putting in a 140A Bosch for that matter. I hate to think the stator serves no useful purpose, but I wonder if it's really necessary in a van with a 200HP 6.0.