Any thoughts on the best way to mount jerry cans on a Discovery roof rack? Is a mounting frame essential, or can one make do with rathchet straps or bungees?

All ideas received with thanks.

Mark J

Assuming the rack is up to it (a Brownchuurch is exactly 8 jerries wide I believe), then a metal bar or pole of wood bolted across the rack in front and behind will stop most of the movement, and a rachet over the top will keep them in place.

Chris S

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Morocco Overland 4 pre-order for Xmas • Trans Morocco Trail

Brownchurch make a roofrack which neatly holds four jerry cans. I would recommend the one with front pillar supports and rear supports. I cant confirm whether this fits the Disco though. If the brownchurch dowes fit then I would also suggest that you flip the rack round however, such that the cans are mounted on the front of the rack. This will cost you a little top end speed but will improve handling / weight distribution.


The Eazy Awn rack which attaches to your gutters is flimsy according to those I have met with them. The last thing you want is a rack on the move.

On number of Jerry cans I would limit myself to four. I took six but despite a leg of 802 miles Gao - Tam I only used 180 litres which comprised of main fuel tank, sandwich tank (under defender wheel arch) and four jerry cans. Tdi's are very efficient do you need the extra weight drag? Keep your Landie light is my motto now. However if you've got a V8 Defender I'd go for a large internal auxilliary tank which doesnt stress the roof and enjoy myself!

One other condsideration when looking for a roofrack is do I want a rooftent? If so a good option is the Eezy-Awn they concertina out over the rear of the vehicle and will not interupt your forward Jerry can arrangement.

Another packing tip, you need to check the padding you use around your jerry cans or you will find the packing has worn through around stress points. Metal against metal on corrugations will soon cause you problems.

Thanks for the usefull advice. The vehicle is a V8i discovery and the rack does mount on the gutters. I actually get around 300 miles on the standard (89 litre) tank. 4 jerries would almost double this, though I suppose consumption will increase on the pistes.

I used an Eezy-awn roof tent in southern Africa last year, on top of a Toyota Hilux. Marvellous piece of kit! My rack is a half length, leaving the Disco's roof bars clear at the front of the vehicle. I think I could get a roof tent up there, with the ladder coming down to the side.

Incidentally, I've heard isolated stories of dangerous situations with jerries mounted at the front of the rack. If one leaks you can end up with the windscreen and bonnet flushed with fuel!

Thanks again for the advice, and to Chris too, for his post.

Regards

Mark

Are you using Eezi-Awn mountings for the roof tent? If so, then are they the older type that do not have the angled aluminium spacers to enable the nuts to tighten up without bending the gutter mounting bolts? If so you need to replace them with a set of the new longer gutter mounting bolts plus the spacers from Footloose4x4. The older mountings may cope with Southern Africa, but they cannot handle Algeria.

Are planning to put the jerry cans on the detachable mounting bars that fit between the roof bars at the front of the vehicle’s roof? This won’t work because the mounting lugs are much too flimsy for the Algerian piste, in fact I’m not sure they would take the weight of four full jerry cans (that’s over 80 kilos) after a few bumps on a tarmac road.

I would recommend carrying them inside the vehicle as close to the rear axle as possible, putting lighter stuff on the roof in a Thule carrier if you don’t have enough space. If the jerry cans are not fairly new buy some new seals from Brownchurch, then you shouldn’t get any petrol vapour inside the vehicle. I’ve carried eight jerrys full of petrol inside vehicles with no problems even though the temperature in the shade was over 50ºC.

If you must put your jerry cans on the roof, then I suggest you consider getting a full length roof rack. If you stick with Eezi-Awn then remove all the rail that goes round the outside as it gets in the way when you’re putting the cover back on the tent. Most of it unbolts, but there are a couple of rivets that need to be drilled out and then replaced with bolts. In my experience with Discos, the Safety Devices roof rack is the best, but it has a rail welded all round the top which means that your roof tent won’t work unless you cut a chunk out. Safety Devices will make up a custom rack without the rails. Cost is approx GBP450 with a lead time of around six weeks.

The danger of jerrys full of petrol is not spillage - as it evaporates pretty quickly. The real danger is static electricity. Your vehicle can build up quite a charge in the heat, so the rather large spark generated when you ground it by touching an open jerry can of petrol to the opened fuel tank filler full of petrol vapour could be the last thing you ever see. To avoid this, bang your hand against both vehicle and jerry can to discharge any static build up and always use a rubber Jerrycan nozzle. Anchor Supplies sell ex-MoD ones very cheap. The other thing you need to be aware of is that pressure builds up inside jerry cans and they tend to squirt petrol out if you don’t get the lid open cleanly. The trick is to stand astride them as far back as possible with the spout pointing away from you.

I’d expect a V8 to do 5km per litre in the sand, not on tarmac. That’s what we got out of the 110s in Saudi Arabia. Have I got my sums wrong? I make it that 300 miles on 89 litres is 5.4km per litre, ie 15.3mpg.

Hello,

I friend of mine is driving a V8i Disco (3.9L) on 245/75R16 in the desert.
For her recent Niger/Tenere trip she had 9 jerrycans on the roof and 5 inside the car (or was it more?).
She has an average (mixed piste) of 25-27 L/100km so worse than 4km per liter. For pure dune driving expect 35L/100km.

My 3.5V8 Ranger Rover is slightly more economic.

Consumption depends also on the tyres and pressure you are using. Higher Tyres (e.g. 235/85R16 or 7.50R16) run at lower preassure on soft ground reduce fuel consumption. So on piste better 1.5-1.7 bar as 2.5 as on tarmac (depends on your load "bien sur").

Loading: put the heavy bit into the car first and drive carefully and slowly with a heavy roof load, 100km/h on corrugation could otherwise shorten your holliday...

When I put jerrycans onto the roof rack (Hannibal) of my Range I use 1 ratchet-strap per 2 jc and I put thin wood between the cans and the rack. I try to load them over the B-post of the car, not to overload the windscreen frame. The optimum is to provide 2 kinds of fixation for the cans in case one works loose, e.g. a simple frame + 1 ratchet-strap.

Bye, Yves



[This message has been edited by Yves (edited 11 July 2002).]

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Yves

Hi All,

I can't stress enough the effect of having jerry cans on the roof has on the vehicles handling!! It is dangerous.

I travelled around Moroc with 6 cans and a tyre on the roof - the vehicle wanted to fall over (landy by the way)! The girlfriend very nearly turned the us over on a straight road at 40mph! PLEASE keep them inside, as long as they don't leak they will be a lot safer in the event of a crash or roll anyhow.
Keep light stuff on the roof, if your'e not convinced, try it at home and swing it about a bit.

Steve.

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Have no regrets!

I would agree with Stumpy on this one - if you can avoid putting jerries on the roof do so. The lower down your weight is the better.

If you do have to put jerries on the roof, ratchetting them down with a board underneath to spread the load should stop them from shift too much. Also consider some padding in between the cans, to protect them a little.

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Jon Harbour

Middle East Off-Roader
http://www.mid-east-off-road.com

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Jon Harbour

Middle East 4x4

We travelled in a 110 from UK to RSA via west / central / eastern africa. We had between 4 - 6 jerry cans on the roof - all 20 litre, fuel and water. They were the last to be filled so where we didn't need as much fuel, we left them empty. We didn't have any major problems with the weight. We started by racheting them but moved to putting a chain across in front of them through the handles, and padlocked on to the roofrack on each side with rachet strap over the top. (chain is an easy fix where as bar has to be obtained). We didn't get any real adverse handling, admittedly the roof rack bolts on to a full roll cage, don't know how well it would work straight onto gutter rails. If you can get it down in the vehicle then great but this really wasn't a big problem having them on top. Eventually corregations and stone based roads in Ethiopia caused the welds to crack on 2 fuel jerry cans, would of been better in a proper rack but that costs more money. Picked up two really good racks from Safaricentre in south africa, imagine footloose probably sell them here but for a bit more money.

The effect of jerries on the roof will much depend on how much load is below. In the Libyan Desert we put 30 (!) 20l jerries of diesel on the top (plus two spare tires) of HZ75 Landcruisers (which are higher and narrower than Landrovers), but with 800-1000 kgs of load below, stability is not a problem (except dune crossings, which require triple care). If you have an empty car with just two people, six full jerries on the roof may have a much more upsetting effect.

My rule of thumb is that you can put about 1/2 of the weight on the roof than what you have on the baseplate below. (Any comments on this from anyone ?)

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Happy Travels,
Andras

FJ Expeditions

After the usual, 'as little as possible', you can actually put a huge load up there (if you have to).

Your biggest problem on any sort of Land Rover is that the gutters will give very quickly - which is messy, expensive (and stops the doors opening!!). Been there, done that...

If you need to put a lot of weight up top, then you need some way to get it supported by the chassis, not the bodywork. (One or the other, you cannot attach your 'rack to both, they are designed to flex differently as you travel).

Lastly, you can always fit HD springs, this will reduce your roll significantly...

Sam.

Andras, according to my rough calculations, you are saying that you had approximately 600kgs on the roof! If what you say is true, I would consider that to be extremely dangerous!

Hello Diff

Your calculation is pretty correct, I did not write the post to try this at home

I was rather illustrating the point that correct load distribution makes all the difference. With another 1000 kgs below (180 l fuel in main tanks, about 400 litres of water, 4 people, food, luggage, etc.) the centre of gravity is not higher than if you would have 200 kgs up on the roof with an empty car. Note also that there is no way you could pack this weight on anything but a -75 'cruiser. With careful driving we encountered no stability problems whatsoever on numerous trips - however itinerary is specially planned to avoid anything but flat terrain for the first 600 kilometres, by which time about 150 kgs come down as fuel is used up.

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Happy Travels,
Andras

FJ Expeditions

I'd like to confirm Andraz experience (in 2001 I was one of the people contribution to the 1000kg ballast on the baseplate :-)
It might be considered amazing, but it is entirely true.

I often observe that the roof rack is loaded to get max space inside the car for sleeping etc. This constellation is the most dangerous one I beleive, especially with only 2 people and not much load (not much water/fuel/food because of short trips) in the car!

Another week point of many 4x4, especially modern Land Rovers: uprated springs without suitable or even tired shock absorbers (coil sprung 4x4 are more sensitiv)!

Happy desert travels, Yves

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Yves

If I remember rightly, Land Rover gutters are only designed to take a maximum load of 100 kilos. I strengthened mine as the roof rack weighs most of that.

András is making a good point about centres of gravity, but there is a big difference between stability on tarmac at 90kph and stability in dunes at 50kph. My Disco has 25% uprated springs. With a full length Eezi-Awn roof rack, Eezi-Awn roof tent, second spare wheel and an awning on top, going into bends above 70kph is pretty scary I can tell you. Things are fine off tarmac.

Without wishing to start up another TLC versus Land Rover debate, I think it’s fair to say that the TLC is a stronger vehicle than the Discovery. Although 600kg on top with another 1,000kg inside must be pushing the axle weight limits of any 4WD.

On a TDi Disco you are allowed an extra 150kg on the front axle and 600kg on the rear axle - but not both together. A V8 can take a bit more on the front axle as the engine is lighter. Having said that, I reckon a TDi can take 800kg without a major risk of structural damage to either the suspension or transmission. But go above 1,000kg and you’re pushing your luck.

Mark, your hand book should tell you the axle weight limits and the EU (or EEC) kerb weight of your Disco. The EU kerb weight is calculated using an empty vehicle plus a full tank of fuel plus a 75kg weight on the driver’s seat. You local municipal tip or any commercial recycling centre should have a weigh bridge. Stick everything on your Disco, fill the tank up with fuel and find out what it weighs. Then add 20kg for every 20 litre jerrycan of fuel and water that you are going to carry, plus your weight and that of any companions (though this can be a tad tricky with some females).

If you are too heavy, leave things behind - no matter how essential you think they are. It’s better than breaking your vehicle in the middle of the Sahara.