Install two/2nd Battery in engine compartment T1N Sprinter

SprinterLex

2006 T1N 2500 & 2006 T1N 3500 @ Canada
Video on how I installed two batteries in the engine compartment.

Note: New battery size options, (yes the new battery spot is not massive but it can hold the stock battery and the old battery spot can hold a massive battery, especially a long battery if you remove the tiny lip on the front of the battery tray)

~ Height = mine 6 3/4" (Max or close to Max)
- possibly can do 7+" with/without mods
- Possible helpful mod is to remove the tiny metal lip that the bottom left front of the battery hits. I think my battery may sit on it...
- I did remove two bolt like things on the floor where the battery sits. Not sure if the battery bottom would actually hit it but I removed it anyway.

~ length = mine 11" (Max or close to Max)
- possibly do about 1/4-1/2" more without mods or big mods. Possibly removing that bottom left front metal lip would do it.
- I installed through a headlight hole and one size bigger battery I could not turn the battery to its spot. Perhaps if you go through the top or mod.
- Guessing there may be a chance to install a 12" battery in there if you really determined, with mods. But that would be absolute max is my guess.

~ width = mine 6" possible max
- I'm thinking 7" may be possible if you do the below mods and are determined but I think that is absolute Max.
- Top left corner hits the plastic part of the air filter housing, bottom left hits the steel lip.
- Possibly can get more width by removing a bit of metal from that steel lip.
- Possible can get more width by removing the plastic tabs on the air filter box... You might have to remove those tabs anyways come to think of it. I remember removing mine but not why.


 
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PrisonTransport

New member
Nice man. I've been thinking about how I wanted to add a second starter battery under the hood as well. My idea was behind the driver side headlight due to the fact that I do not have the Aux Heater installed on my 05 3500 158". For some reason I never thought about the passenger side. So is the original battery holder used for your "House" power? Or are both are for starting power?
 

SprinterLex

2006 T1N 2500 & 2006 T1N 3500 @ Canada
Where would Recommend to install your battery?
- If you do not have a stock heater I 100% recommend installing it on the driver side.
- You will save money with wire length is a big reason and it will be easier to install.
- You will also avoid all the hassle with the heater box being in the way. More space on the driver's side.
- I used the original spot for my House battery, Just because I can fit a way bigger battery. I have a 120AH used gel battery there right now.
- haveing the starter battery under the light is annoying to unplug negative when working on the van. I can control the power flow with the switch I have on the red wire.
- I may change up my system to install the secondary battery under the driver seat with my 5kw diesel heater. I think I might be able to fight my 120ah gel battery and heater both under the seat... At least going by my measurements. It's very tight and the battery has to be sideways.
- reason to move the battery inside is I read that lead-acid batteries lose 50% of Ah usage at -20C..... Haven't looked too deeply into that. yet.

Which Batteries power what
I have a rather complicated design of switches. Depending on which switches I have on or off it can do many things.
- I can have either battery run the sprinter, House, or both.
- I can also set it up so both batteries are connected and both running house ane sprinter
- I can disconnect the house load at any time with one switch turn.
- I also have it set up that I can plug in an extension cord into the number harness which turns on a Genious10 battery charger.
- When the extension is plugged in it can charge the house battery or the starter battery or both.
- When the extension is plugged in it switches the ac power in the back to the extension cord.


Standard switch set up.
- When a car is running and the starter battery is full an isolator allows power from the alternator to then charge the second battery.
 
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SprinterLex

2006 T1N 2500 & 2006 T1N 3500 @ Canada
Update report

The cliff notes:
~ I think the smaller battery is not powerful enough for the van for the cold Canadian temperatures.

~ I just installed a brand new refurbished used battery and let the van sit for a month.
~ At -20c ish (-13F) the van didn't start, just clicked. I boosted the van with tremendous difficulty it eventually started.
~ I left it running for 2 hours and then drove it 20 mins. I turned it off then tried to start it right away but it didn't start. I assumed battery was done.
~ I started van up and drove it home just over an hour away, all hwy. I let it sit for about 2 weeks.
~ I just went to try and start it for giggles at -1c (30F) and it started up... This makes me think it's not a power drain but 100% battery size is problem
 

marklg

Well-known member
Update report

The cliff notes:
~ I think the smaller battery is not powerful enough for the van for the cold Canadian temperatures.

~ I just installed a brand new refurbished used battery and let the van sit for a month.
~ At -20c ish (-13F) the van didn't start, just clicked. I boosted the van with tremendous difficulty it eventually started.
~ I left it running for 2 hours and then drove it 20 mins. I turned it off then tried to start it right away but it didn't start. I assumed battery was done.
~ I started van up and drove it home just over an hour away, all hwy. I let it sit for about 2 weeks.
~ I just went to try and start it for giggles at -1c (30F) and it started up... This makes me think it's not a power drain but 100% battery size is problem
What is a "brand new refurbished used battery"? I know of no way to refurbish a lead acid battery. The battery is a used battery and may be weak. They only get worse with time. You also may have a power drain, which is common with these vans.

Regards,

Mark
 

SprinterLex

2006 T1N 2500 & 2006 T1N 3500 @ Canada
What is a "brand new refurbished used battery"? I know of no way to refurbish a lead acid battery. The battery is a used battery and may be weak. They only get worse with time. You also may have a power drain, which is common with these vans.

Regards,

Mark
Idk, I just know that car battery is one of the most recycled things in the world. Also there is a place in Calgary with awesome reviews that takes old batteries, fixed them, and sells them again. Or maybe I got their business wrong, idk l, lol.
 

SprinterLex

2006 T1N 2500 & 2006 T1N 3500 @ Canada
I'm check for a drain now. I turned on my cur off switch and seeing if volts go down in the morning. :)
 

marklg

Well-known member
Idk, I just know that car battery is one of the most recycled things in the world. Also there is a place in Calgary with awesome reviews that takes old batteries, fixed them, and sells them again. Or maybe I got their business wrong, idk l, lol.
They completely dismantle them and re-refine the lead to make new batteries out of recycled. The lead plates start to disintegrate and stuff falls off. I suppose they could take the crud off the bottom of the battery if it was shorting things out and delay the inevitable, but the stuff that fell off means there is less good battery left. I don't know of a way to add material back to the plates. It may be possible that the water level was low or the acid solution was bad, but anyone could add water or acid.

I'm check for a drain now. I turned on my cur off switch and seeing if volts go down in the morning. :)
You won't be able to tell with a voltmeter. Lead acid batteries change voltage with time and temperature on their own. You might be able to tell if you let it sit for a couple weeks and see a constant downward trend. You need a current meter. If the drain is fairly large, a clamp on DC current meter can measure it.

Regards,

Mark
 

SprinterLex

2006 T1N 2500 & 2006 T1N 3500 @ Canada
You won't be able to tell with a voltmeter.
Hmmm thanks Mark, I'll have to look into this... I'll fix the battery size issue than disconnect the batteries with a switch until I have the tools to figure out of there is a drain.

I do realize my cluster display is not as bright as it should be during the day. My other van is bright during the day then dims with the lights on or something. This one stays the same dim all the time. That dim info is off the top of my mind, without looking too deep at it. Regardless could point to an electrical issue.
 

tinman

Well-known member
About 50 years ago I knew a guy who had a pretty robust business selling "refurbished" batteries. He bought the scrap batteries from auto maintenance shops (lots were service stations back then). The batteries would get a fluid top up, then several hours on heavy charge. He'd do a quick load check, hydrometer check of the cells, and if they checked out OK they got cleaned up and sold with a replacement warranty. The ones that failed went to scrap dealers for about the same price as what he'd paid for them. Surprisingly few came back. He figured a reasonable percentage of the batteries he bought were warranty returns of fairly new batteries that came from cars with charging faults.
 

SprinterLex

2006 T1N 2500 & 2006 T1N 3500 @ Canada
UPDATE: (Installed a bigger Battery)
~ 75ah gell battery (Changed it to a house battery)
~ battery installed depth is now 8 1/8 to 8 1/4 (Installed on it's side)
~Fit's YELLOW TOP OPTIMA battery (I'm 97% sure you could fit a 55ah yellow top optima battery)

Video Link:
 

SprinterLex

2006 T1N 2500 & 2006 T1N 3500 @ Canada
You won't be able to tell with a voltmeter. Lead acid batteries change voltage with time and temperature on their own. You might be able to tell if you let it sit for a couple weeks and see a constant downward trend. You need a current meter.
What I did:
~ Installed a battery monitor based on the knowledge you shared.
~ I have the van sitting and hooked up to the "house" deep cycle battery. (battery is only hooked up to van's stuff, not the "house" electronics)
~ Battery hooked up for the test is a gell, 75ah, deep cycle battery.
Note: I'm not so worried about battery draw now that it's on a deep cycle battery for the test to see if there is an electrical draw.

Questions?
~ How many amps is a normal draw on a T1N sprinter? (Not sure if my monitor can detect tiny normal draw amount)
~ How many amps is normal to lose per day? (My battery monitor tells me how many AH the battery loses and receives. All power must go through the monitor on the negative wire.)

The test being done now
~ I just have the van sitting for as many days as it needs to sit to determine if I have an abnormal amount of sitting power draw.
~ About how many days should I let it sit?
 

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