Stag Battery in Boot

[Rumbo]

While I am progressing with fitting an A/C system I needed to sort out a better power distribution supply for the electric fan, AC clutch and future headlight relays. I also needed to free up space to fit a new radiator overflow bottle and the windscreen washer bottle as well as give more space for the new AC compressor ............so I decided to relocate the battery to the boot.

I had done a similar job on my Alfa so I knew what was involved and what parts I needed.

First task was to construct a tray to hold the battery on the left side of the boot. With some mild steel sheet and some brackets from the hardware store I made a battery holder, bit over engineered but I tend to think a bit more is a bit better than just enough. Its not pretty but solid and managed to use the two existing threaded screw fittings in the left boot area to secure the rear of the holder and welded a bolt to help secure the part of front of the battery holder.

I also used the left rear bumper bolt as a securing point to hold one of the battery hold down rods and drilled a hole on the other side of the holder for the other hold down rods. Need to tidy it up and make the hold down bar then on to creating a suitable path through the inside of the car to run the large #2 size power cable up to a new power distribution point in the right hand side of the engine bay. DSC00379 (1024x768).jpg

[Phil S]

will the spare wheel fit under it?
considered putting mine behind the rear seat so it sits under the hood when folded down, that way you can go smaller 6v in series to give greater amps

[barkerwilliams]

Looks good, Don't forget to tell the insurance company as a rear battery might be viewed as a greater fire risk in a rear-end shunt. Don't give 'em any reason to dispute a possible claim.

Alan

[new to this]

Looks good, Don't forget to tell the insurance company as a rear battery might be viewed as a greater fire risk in a rear-end shunt. Don't give 'em any reason to dispute a possible claim.

Alan

Good point, hadnt thought about the insurance

[stag8manod]

Hi, My battery is in the boot but is mounted under the upturned spare wheel, spokes up, in a modified Spitfire battery box to compensate for the Stag boot floor angle, through the floor. It's a standard sized battery and just fits with a flat rubber lined lid to prevent any possible short circuits. I had to put a small offset in the r/hand exhaust pipe to clear the corner of the sunken battery box. Also to facilitate jump or boost starting i have run Positive and Negative cables out to the tow bar where the positive cable is mounted in an isolated fitting. There is also a permanently mounted and wired trickle charger in the hood well that is plugged into on the towbar. Under the bonnet next to the r/hand strut tower is an isolating key with a 3 amp bypass fuse which keeps the clock alive and blows if an attempt is made to start the engine.
Originally I moved the battery to the hood well and it fitted and worked well but with increasing years I found I could not reach into the centre of the hood well and lift the heavy battery in or out.
Why did I need to move the battery? I used the space to install a Kenlowe electric water pre heater and a 12v auxiliary oil pump which runs for 14 secs. each time the ignition is switched on to prime the lube system every prior to starting.
Cheers Ian A

[STypeR]

Rumbo, how far have you progressed on the AC? Are you using a factory unit or do you have one of the Aussie made hybrids that were installed here?

[Rumbo]

The battery tray is finally finished and yes the spare wheel fits in with room to spare. I just need to weld an earth point. Please excuse the state of the paint work as this will be the last item to be rectified when all the mechanical and electrical modifications have been done.

I will now run the #2 gauge battery cable over the LH rear wheel well then under the rear seat, down the RH side of the transmission tunnel, through the fire wall the up to a power distribution point which will join the alternator, starter and the fuse box that will power the relays for the lights and the AC compressor clutch and electric fan.

I will then go back to fitting the rest of my AC system, namely the condenser and the compressor. I am using an aftermarket system purchased from a QLD supplier Speedy Air Sales. I have already fitted the evaporator where the glove box was so will continue my updates in my AC thread.

The fun continues!

[Alanfp]

Slightly off-topic, perhaps, but jump/boost starting was mentioned in a post above...

I used one of those tiny battery boosters to start my Focus when the battery went flat once. No need for trailing jump leads.

Unbelievable bit of kit - practical, neat, clean, quick, small, keep in glovebox (especially if you've got a USB socket in it!). Obviously not a solution if you've flattened your battery because you've been turning over an engine that doesn't want to start.
Arteck Car Jump Starter Auto Battery Booster and 8000mAh External Battery Charger Car Jumper for 12V Automotive, Motorcycle, Tractor, Boat, Phone with Clamps, LED Flashlight, 300A Peak 2.5L Gas Max


NB I am not recommending this particular make or model - do your own research.

[marshman]

Nice job.

I would also recommend fitting a vent tube from the battery to the outside world. If the battery is slightly overcharged on a long run it will vent hydrogen and oxygen - a nice explosive mix! Then when you get home you open the boot, the switch for the boot light makes contact to turn the light on, small spark and boom! Unlikely but theoretically possible! The boot is largely sealed with little or no airflow unlike under the bonnet so gasses can build up. Most if not all modern car batteries have a tiny vent hole on either side at the top, you can insert a small plastic tube in there. All modern cars I have seen with a battery in the boot have this tube connected - my wife's MX5 being one of them.

Roger

[new to this]

Shouldnt that battery be fully enclosed in a box ?

[marshman]

Doesn't need to be. As long as it is secured it is fine. Neither our MX5, or sons BMW 1 series batteries are boxed, and they are both mounted in the boot.

[Rumbo]

Thanks guys for the suggestions, I will check with my insurance. Also I have now made a battery vent.

I used some left over reticulation hose and elbow connector for the vent hole next to the positive terminal and feed it down out through the floor pan. The other side I used a red plastic plug to block of the other vent hole near the negative terminal. I saw some battery vent tube kits often had one tube and a plug so it looks like one vent hole should be enough to vent any possible gasses even though they

Battery vent tube (1024x768).jpg would be very little.

You can also see the battery cable will have a 150Amp cube fuse holder that attaches to the positive battery terminal which will give protection in case of an earth.

Now to feed the rest of the battery cable through the car.

[mjheathcote]

Slightly off-topic, perhaps, but jump/boost starting was mentioned in a post above...

I used one of those tiny battery boosters to start my Focus when the battery went flat once. No need for trailing jump leads.

Unbelievable bit of kit - practical, neat, clean, quick, small, keep in glovebox (especially if you've got a USB socket in it!). Obviously not a solution if you've flattened your battery because you've been turning over an engine that doesn't want to start.
Arteck Car Jump Starter Auto Battery Booster and 8000mAh External Battery Charger Car Jumper for 12V Automotive, Motorcycle, Tractor, Boat, Phone with Clamps, LED Flashlight, 300A Peak 2.5L Gas Max


NB I am not recommending this particular make or model - do your own research.

They are wonderful things, on drive it day last year my battery failed 100 mes from home. Suddenly wouldn't deliver any amps to engage the starter, but fine when running. Saved the day.
I did the ultimate test with the jump pack, no main battery at all, turned over just fine!

[Rumbo]

battery cable 1 (1024x768).jpgbattery cable 2 (1024x768).jpgbattery cable 3 (1024x768).jpg
Next was to run the main positive battery cable over the left rear wheel arch. I have covered the battery cable with split conduit and also some foam tube over the wheel arch to minimise the cable moving and any chaffing against the body. I have put some off cuts of rubber door seals on any edges the cable is next too as a bit of extra protection from wear.

The cable then runs under the seat which has a convenient void so that the rear seat will not impinge on the cable.

I made a hole near the RH side of the transmission tunnel ensuring it did not have any sharp projections to rub through the cable conduit and tried to keep the bends in the cable as smooth as possible. The cable was secured by some cable holders before existing the car near the firewall.

I need to crimp on some cable lugs and will also solder them before applying heat shrink on the ends so that they can join up with the power distribution box.

[marshman]

You say you have a 150 amp cube fuse in the positive lead. I would be a little concerned that it is not rated high enough for the starter. According to the R.O.M. the "light running" current (i.e. no real load) is 80 A. The stall current is 475 amps and it quotes 280 A at 9V - 1000 rpm and 7 lbft torque, which I assume is cranking load.

I have just measured mine, engine sitting cold (20 deg C) but not winter cold! and the current clamp meter on the battery lead read around 120 A whilst cranking, much higher on initial close of the solenoid contacts - I did have the coil disconnected so the engine would not fire.. I would not be at all surprised if the cube fuse blew, if not on the first start then fairly soon after when trying to start. Even if you have a nice shiny new high torque starter I would think you risk a blown fuse when the weather gets colder, oil gets thicker and engine is harder to turn over. and the peak current as the solenoid closes will be around 4 to 500 A for a fraction of a second which may well blow a 150A fuse instantly. Cube fuses are available up to 300A. I would fit the highest you can, it will blow if there is a short on the battery leads which is all you are concerned about. Personally I would do away with it all together, you seem to have taken adequate precautions with the positive battery lead and they are not usually fitted to cars as far as I know.

Roger