Jump starter pack or battery charger for 7.3L Diesel?

[eyesunderground]

We're to determine the best emergency option for starting our 7.3L Ford diesel bus. We got stuck in the middle of nowhere on our first trip last weekend when it wouldn't start, so now I'm planning for future situations.

I'm considering either a jump starter pack like the Jump-N-Carry (JNC950) which is commercial grade and the specs seem like it should work fine for this engine. I've also seen the Noco Boost which the larger models seem like they could also work and get pretty decent reviews. Not sure if a smaller JNC would work.

But I'm also considering something like the Ctek or Noco Genius battery charger which should charge the battery in a few hours. I've pretty much ruled out the trickle charger for on-the-road situations (but I can be convinced), and will likely pick one up for when it's parked at home.

I will almost always have access to at least some A/C power through our house bank/solar option, if that helps.

We recently replaced both bus batteries, so I'm working on identifying any parasitic draws, but want to have something that will work regardless of any success I have solving the main issue. We also realize that the temps were pretty cold that morning, so it may have also had something to do with being unable to get started.

What are you all using to either jump your buses or keep the batteries charged? Anything in particular I should look for (or avoid)?

Thanks in advance!

[john61ct]

Not comparable choices.

The jumper pack is more likely to work, and without a long wait, but you need to keep it topped up and test it every 3mo or so. Don't use it to power phones etc.

If you have a proper House bank you could jumpstart off that, no AC power involved there.

What power source were you thinking would recharge your battery that quickly off grid, solar or generator? When you have shore power then a quality high-amp charger is all you need, trivial issue just money.

Learn how to verify you are actually getting to 100% Full regularly, and determine SoC otherwise.

Your energy input must average higher than your daily outgo.

[family wagon]

The vendor says their pack will work for starting engines in most class 1-6 commercial trucks, but... I'm still skeptical. Can I rely on it to crank my 8 L engine when temperatures are below freezing, the grid heater needs to run for 30 seconds before cranking, and I still might need a long crank -- after the jumper pack has been forgotten on a shelf for many months since the last time I used it?



I can believe a jumper pack would get the job done on a good day, or even on most days, but a "works, usually" grade backup plan doesn't help me sleep better at night. I'd rather have a mains-powered high-amp charger.

Originally Posted by john61ct

What power source were you thinking would recharge your battery that quickly off grid, solar or generator? When you have shore power then a quality high-amp charger is all you need, trivial issue just money.

Even from generator a high-amp charger can work. Mine runs 40 A into the battery at its highest charge mode (about 500 watts) and about 100 A in its "engine start" mode (a bit north of 1 kW). Almost any generator would support that.


Note that I can't actually start my engine directly with my charger's engine start mode -- my starter pulls about 300 amps. My charger runs its 100 A output for about 20 seconds, I let it cool for maybe 30 seconds, then run it through a second cycle. That usually puts enough charge into the battery to start successfully.

[john61ct]

Yes as I said, with high amp shore power available this is a non issue.

I assumed you were talking off-grid.

[eyesunderground]

Thanks for the responses. I was talking completely off-grid, with no shore power.

We are currently running a GoalZero 1400 with 100w solar panel as a temporary solution until I have time to spec and build a better house system (got the GZ a while back for Xmas to run power at the beach for a projector and laptop for beach movie nights), but it's not ideal as a long term solution. I realize a better (and bigger) system should have no problem powering a battery charger.

I assume(d) that I could run the Ctek or Noco charger off of the GZ to charge up a depleted battery, if necessary. But, maybe it doesn't have enough juice to get the job done. I'm still learning up on the electrical side of things.

[john61ct]

Originally Posted by eyesunderground

Thanks for the responses. I was talking completely off-grid, with no shore power
…
I'm still learning up on the electrical side of things.

Wow, yes

Forget about gadgets like the GZ as a power source for cranking or charging, consider that a destination for charging only not a source.

Do not consider running a battery charger from batteries.

Sources off grid include generator or solar or your alternator, but in this context that last is unavailable.

So that leaves a House bank much bigger than your Starter battery to jumpstart from.

Keep it fully charged from just solar - need a lot to get to Full quickly,

or from both a genset, run in the early AM for a few hours, followed by solar for rest of the day.


A big LFP bank can just use the gennies, if lead the solar is required, takes 7+ hours to get to Full.

Those little chargers are for when shore power is available all night, for genset charging you need 40-60A rated minimum.

Keep the lithium jumpstarter as a backup, for when House is too depleted to jump, and you can't wait for many hours or days

[BlackJohn]

Agree on the jump start for backup only because if your bus doesn't happen to start with a boost then you are stranded when the jump start pack gets depleted. A no start can happen from many issues and can be an unexpected occurrence.

Not sure how many kicks at the an a jump start pack would give you. Start system is enormous draw on good batteries.

Just pay attention to this part of your start system as if your life depends on it which it very well may someday.


Carry booster cables also or do the wiring required to boost from the house batteries.


John

[TJones]

I think a generator and a 40 to 60 amp AC battery charger are your best option. Depending on how discharged the start battery is it would be difficult and possibly damaging to a house bank unless the house batteries are rated for engine starting. A jump pack is probably a one chance option. If it does start on the first couple of attempts the pack would likely be depleted. The other advantage of the generator is it could be used to power an engine block heater in cold weather after charging the batteries.

Ted

[Defjr333]

For me, I prefer having the ability to jump the vehicle from the house batteries at any time with a high current isolation switch. In one setting the alternator charges the start and house batteries, but does not allow for current to flow FROM the house batteries unless turned to the other setting. Along with the proper DC to DC converter/ charger(multi stage) it gives me small chargers to all batteries on short trips, but is mostly useful on longer duration ones. Along with a high current alternator or 2nd alternator in some set ups, it can be very useful. The isolation switch also allows me to charge the start battery from my solar panels, shore power, or generator in its second setting. The switch and converter are not cheap tho. Together they can run as much as $400. But for the peace of mind of never being short of power, it was worth it. May not be something you want, but I figured somebody one day may read this thread that will find it useful.

[family wagon]

There's one other thing we should clarify: almost universally, when somebody writes "generator" on skoolie they're referring to a machine that burns fuel to generate electricity. By way of example, an EU2200i will burn a gallon of gasoline in 3.2 hours producing its rated 1800 watts. That's about 5.8 kWh from a gallon of gas and it's easy to carry several gallons.



GoalZero and their imitators haven't helped things by calling their devices "generators." Under the covers it's a battery pack and an inverter so here we tend to think of that more or less the same as a small house battery bank. The GZ 1400 carries about 1.4 kWh and when it's depleted you can't just pour in another gallon of gas.


Don't get me wrong; those power stations do a great job at what they do. It may have more capacity to recharge a dead start battery as compared to a jumper pack. But if I were to run the battery charger I mentioned earlier on its engine start mode from the GZ 1400, I'd get four charge cycles which enough for me to make two starting attempts. It's definitely better than nothing though, especially since it's already on hand.

[Truthseeker4449]

I can't speak on the other ideas others have suggested here, but I can give you my experiences with less powerful model of the Jump-N-Carry, the JNC660. Honestly I absolutely loved the one I had while working in an auto shop. Although I never got to use it on a diesel, it jumped everything from beat up pickups to burnt Porsches with no issues, even substituting it as a battery in some situations.

Only negative thing with it is that the jumper leads are always hot. Keep that in mind however you store it, or opt for a model that has a disconnect switch.

For a while my own 7.3 pickup had bad glow plugs and it would drain the batteries significantly trying to start it. Several times I had to grab my little Ranger and run at a high idle for 10 or 15 minutes to charge the batteries back up enough to try again some more.

[john61ct]

The goal should be, not to recharge the Starter battery, but to directly crank the engine.

This is no strain whatsoever for decent size and quality House bank, in fact a trivial load.

Blue Sea ML-ACR really can't be beat for that purpose.