Overland with Kids

We’ve been struggling with vehicle jacking solutions for both caravan and vehicle - i.e. the weight of carrying a 3T trolley / bottle jack in the rear of our vehicle along with all our other items. Not so much even about the weight-load in the vehicle itself but actually having to contend with physically lifting a jack in and out like this when needed (quite heavy). We considered a more portable hi-lift jack but quite dangerous with risk of damaging the vehicle and ourselves if not used properly (and we are inexperienced), so this led us into to a bit of a quandarry as to what to do.

That is until Paul Maisey, from Perth in Australia, put us on the trail of vehicle lift bags / air bag jacks or, bull bags as they are more commonly known in Oz.  We’d never heard of them before but air bag jacks are tough vinyl balloons the size of a dustbin which are inflated by the car’s exhaust (can also use compressor) and can easily lift one side of a 4WD.  Internet research followed and we also accidently found an exert from Chris Scott’s Sahara Overland book as follows:

“Air jacks are a rare sight in the Sahara where conservative drivers stick to traditional techniques and equipment. However, for effortless sand recovery or even righting overturned vehicles, an air jack is ideal, spreading the weight over a large area and requiring no strenuous or dangerous jacking. I’ve never been a fan of heavy, cumbersome and dodgy high lifts and was happy to replace mine with an air bag which is lighter and requires less effort. The number of occassions when you actually need to jack the car right up are fewer than you think. The bag needs less than 1 bar (10psi) to lift a car so no engine damage can occur, although the exhaust system must be sound if it is to survive as well as fill the bag efficiently. One thing you must give consideration to is where to position the jack: the ideal smooth, flat surface is not present under a 4WD with a separate chassis. Choose the position carfefully or make a load spreading adaptor remembering your lifting half the vehicle’s car weight on this point. At the very least a thick piece of carpet should be used between the undercarriage and the bag - and something similar if thorns or rocks are present”.  And interestingly, on the subject of high lift jacks themselves, Chris says “Light weight people may have difficulty jacking up the rear of a fully-loaded car at all, so practice at home before it’s too late - an air jack is the answer”.

We also asked the Landyzone forum for their views and received some good advice. Redhand re: being able to dig under a boulder and slip the bag in to remove. Batttenberg pointed us to a 4T version on eBay for £60 including delivery on e-Bay. Along with the following advice:

“A few tips for use:

Keep bag it comes with

Use in conjunction with hi-lift and bottle jack as well as bag - all have their uses

Plus bags are prone to tears so might need other means

Make sure that your exhaust pipe is leak free and sound!

Use the engine on tickover, no need to rev!

Make sure that the pipe from the exhaust to the bag is in a big wide arc, with no kinks or twists in it.

Put a touch of air in the bag before attempting the actual lift (if you can). not so much that you trap and cant move the bag, but enough that it will be touching the ground and the underside of your car with enough pressure to be able to move it about, adjust the folds or reposition it slightly.

Put only 2/3rd to 3/4s of the top of the bag under the sill and angle the bag very slightly, inflating very slowly at first so that the bag will create a similar but smaller angle when inflated to how the car will list over…then hit it with full pressure in one hit for the lift. while matey stamps on the brakes.

Make sure that the input hole where the pipe attaches, is pulled out sideways and is not trapped in any of the folds. once pressurised, if the pipe is trapped in a fold you wont be able to release the pressure without a full lift as you cant twist the pipe off, not good if you’ve got it positioned all wrong..!

Use a carpet tile or your rubber footwell mats to protect the bag at the top, it has spikes on the bottom so dont use anything at the bottom unless you fear it’s gonna get punctured.

The sides of the bag are more prone to tearing, keep a lookout for the hockey stick bolts, steps or mudflap bolts that may damage the bag, and if it touches them in danger of a rip, whip out the pipe and deflate rapidly for less chance of a tear.

The repair kit is a waste of time, dont tear the bag.

To bring it down, twist and release the air very slowly at first to control the fall, when the wheels are just an inch off the ground whip out the pipe and get out of the way, otherwise you get a face full of exhaust gas!”….

…..Our thoughts are that we’ll have to have a little practice and maybe we’ll buy a second one (whole kit including bag, valve, repair kit and holdall weighs approx 10lbs - very light) as well as bring hi-lift and a smaller 2T bottle jack that we have plus a spade!

Thanks all for the help peeps - much obliged!

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