Hi Everyone,
Im installing a dual battery system in my 2007 defender with a 2.4 puma engine what i need to know is if my alternator is a stop/start or a smart one in which case i would need a VSR (voltage sensing relay) or is it a standard alternator and secondly i heard somewhere that the deep cycle leisure battery i need must be a sealed one and not one that produces a gas when charging as it will be under the passenger seat next to the normal battery, any advice and tips would be much appreciated thanks

Doubt very much its a smart one and it won't be stop/start just because of the vehicle year (2007). Leisure batteries are sealed, they may have a tiny vent but they don't vent like batteries used to. Just get a std voltage sensing relay, big fuses (50amp) and big cables and follow the instructions. Don't waste time on anything less than 100AH for the leisure battery and follow the charging and discharging instructions to the letter as you can easily wreck a new battery.

rob1miles said:

Doubt very much its a smart one and it won't be stop/start just because of the vehicle year (2007). Leisure batteries are sealed, they may have a tiny vent but they don't vent like batteries used to. Just get a std voltage sensing relay, big fuses (50amp) and big cables and follow the instructions. Don't waste time on anything less than 100AH for the leisure battery and follow the charging and discharging instructions to the letter as you can easily wreck a new battery.

Click to expand...

rob1miles said:

Doubt very much its a smart one and it won't be stop/start just because of the vehicle year (2007). Leisure batteries are sealed, they may have a tiny vent but they don't vent like batteries used to. Just get a std voltage sensing relay, big fuses (50amp) and big cables and follow the instructions. Don't waste time on anything less than 100AH for the leisure battery and follow the charging and discharging instructions to the letter as you can easily wreck a new battery.

Click to expand...

Hi Rob, cheers for that

Most batteries have a vent hole near the top. All you need to do is attach a pipe like washer jet pipe to the hole and vent it outside the vehicle.