Just on a point IanS has raised. You 110 drivers shouldn’t get too hung up on the 48psi that LandRover recommend for the rear tyres. They only need 44psi to carry a rear axle weight of 1,800 kilos - the over inflation is to induce understeer on the rear axle.

I mounted an A/C compressor in the engine bay and after a couple years of use I can honestly tell you that it’s the best modification I ever did. I highly recommend that any serious traveler should install one.

The compressor performance is awesome. It inflates tires jut as fast as a regular full size shop compressor. Since I have 2 outlets, we often use the compressor 2 at a time with no problem. I air up my 31x10.5x15 from 10 PSI to 30 PSI in 20 to 30 seconds. When traveling in more than one car over long stretches of sand and getting stuck often, electric compressors will slow you down severely. Now, my friends don’t bother getting their electric compressors out and just use mine and we still start moving again much faster.

Most important of all, with this pump I can reseat the tire on the rim after repair. That’s something no electric compressor can do.

The whole thing ended up costing me less than a good quality electric compressor but installing it is a bit more involved.

Following is a description of what I did. All these parts, even if they sound alien to you are standard air compressor parts and can be found almost anywhere. Let me know if you need any help with this. It’s very easy once you understand how it works.

Here’s what I did:

The Compressor:
I got hold of an old York compressor. These were used in a number of Mercedes and Volvo cars over the years. There are 3 sizes; I got the biggest one that has a displacement of 10 cubic inches. (If interested I can tell you how to differentiate them). The thing about the York is that it’s a vertical unit with the crankshaft (and oil) at the bottom, so the air doesn’t mix that much with the oil. So very little oil comes out of it, which means less work for the oil filter and longer periods between compressor maintenance.

A metal fabricator made me a mount to mount the compressor right next to the air conditioning compressor in my Jeep. I got a replacement alternator pulley that had an extra groove and connected that to the air compressor with a small belt.

You HAVE to oil the compressor since it’s basically a crankshaft, connecting rod and piston. Would you run your engine without oil?

Input / Output:
I installed a small air filter to the compressor input and an oil filter to the output. Since the York hold the oil at the bottom I only have to top off the oil every year or so. But it has to be oiled.

Plumbing:
The air coming out of the compressor goes through:

One-way valve with pressure relief: This holds the pressure in the tank while relieving the pressure in the airline linking it back to the compressor. This lightens the load on the compressor when it starts pumping again.

Pressure switch: This is connected to the compressor wiring. It turns it on when the pressure drops below 80 PSI and off when it reaches 130 PSI. It is linked to the one-way valve with a thin tube to relieve the pressure when the pump stops.

The Tank: an old fire extinguisher bottle with a pressure gauge attached to it.

Relief valve: Also attached to the tank. When it gets hot the air in the tank expands, thus increasing pressure, the relief valve lets the excess air out and maintain the tank pressure at 150 PSI max.

From the tank I plumbed airlines to the front bumper, the rear bumper and inside the cab. All air outlets are fitted with quick disconnects couplings for fast operation.

Uses:

Naturally I use it to inflate the tires. But I also use the in-cab air outlet to clean my camera equipment as often as I can while driving.

The compressor it powerful rnough to power air tools. I carry a ½ inch gun that comes in handy in a variety of situation, like changing a tire.

Since this thing outputs monstrous amount of air very quickly, I now carry a full size 25 cm thick air mattress to sleep on. It takes me only a few minutes to inflate it and now I always wake up fresh . I also adapted a blender “top” (the thing you put the fruits in, whatever that’s called in English) to run off the air gun . Fresh juice, milk shake or margarita anybody??


As I said above, this is the best modification I ever did and I’m very happy with it. Every serious traveler should have one installed. Let me know if you need any help figuring and installing a similar system and I can get you pictures of my setup if interested.

Take care,

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A.B.
www.ShortWheelbase.com

[This message has been edited by A.B. (edited 21 April 2002).]

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A.B.
OasisPhoto.com – Images from the Magical Sahara.

I was in Cairo not long ago and can confirm A.B.s mods looked very good indeed, he was very pleased with the performance.

Although I did not taste the product of the blender, it is a welcome addition.

Only question was what was that balloon thing being used as a dust stopper on the air line.

We are carrying a 12v job that does work and is fan cooled, better than Halfords, from the States, but doesn't make Margaritas.

Toby, Its nice to hear there was actually somebody else in Libya, as we didn't see anybody apart from a 22 car Italian convoy. Independant travel??

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A Journey of Hope
www.expeditionjasanne.co.uk
www.fugroseastar.com

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A Journey of Hope
www.expeditionjasanne.co.uk

In my opinion the best solution of the lot is to fit a compressor and tank from a Range Rover. The compressor is rated to run all the time, so no over heating problems. Connect this to the tank which fits easily between the chassis rails and is of 10 litres capacity. Install a pressure switch which will stop the comprerssor once you have 160 psi (11 bar) in the tank. Connect your airlines to the tank.

We had the tank installed just in front of the rear crossmember on a 300 Tdi Defender 90. The space is not used by anything else and although tempting to put the fuel tank from a Td5 under there, usually there is enough weight on the back axle as it is.

This will inflate at least three of your tyres (we were running 33") as fast as a garage pump from 1 bar. Sure the compressor has to run for a while to charge the tank back up, but you are driving whilst this is happening.

Others in the group had a variety of systems from twin cylinder electric compressors, through to a/c pumps and even small workshop compressor in the service barge. In all cases we were pumped up and ready to go a good ten to fifteen minutes before the rest of them.

The downside of course was the extra weight in tea and coffee we had to carry whilst we brewed up waiting for the others!

If you don't want to go to the full expense, try visiting the Old Sodbury Sortouts as you will freqeuently pick up the bits as a bargain there.

Wow, what a popular topic!

While agreeing the idea of spending as much as you can afford on a compressor, I have a little tip from a farmer that helped alot on our trans africa trip.

Carry a long piece of hose (long enougth to stretch from your spare tyre to the farthest road wheel) with an adaptor on each end to fit the valves. Then when you get the chance blow up your spare tyre as much as possible. (60-100psi is usually possible.) This can then give you 1 or 2 full tyre refills before you have to resort to a pump.

Tom

Not really advisable. The spare tire has to be in tiptop shape to handle such pressure. A friend of mine blew his spare at only 80 PSI. Also forget to use this technique in hot climates, the air inside the tire will expand and the pressure can easily double and the tire will blow. Air compressor tanks have a pressure relieve valve that lets out heated air out to keep the pressure within the tank specs.

Also you will barley be able to inflate one tire. If you set the spare to 80 PSI and hook it to another flat tire, the pressure will level between both tires to 40 PSI. You cannot pump the 40 PSI in the spare to a third tire. To use the spare to fill 2 tires to 40 PSI, the spare will have to hold be pressurized to 120 PSI.

I would use this method only if I have a new spare and only as a backup to the compressor and never south of the Mediterranean.

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A.B.
www.ShortWheelbase.com

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A.B.
OasisPhoto.com – Images from the Magical Sahara.

Interesting, I thought it sounded too handy to be true...

CS

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Morocco Overland 4 (2025) • Trans Morocco Trail

I agree that a less than perfect spare might blow in hot weather etc., but would this method provide enough fast air to pop the tyre onto the rim when going tubeless? If it just did that and nothing else, then the tyres could be topped up with a compressor. It could save the ratchet strap or bicycle inner tube tricks being tested. What d'you think?

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Pete Sinclair.
Alnwick to Botswana
http://www.a2b.uk.net

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Pete Sinclair.
Alnwick to Botswana
http://www.a2b.uk.net

Pete, I don’t know it if would pop up the tire, I never tried it but I don’t think it would. The tire can hold only so much valuable air and I think a lot of it will escape from the open bed before it has the chance to pressurize the sidewalls and push them to the bed. I have an air tank (about 6 liters) in my engine driven compressor setup described in my post above. It’s compressed to 130 PSI and it barely reseats the bed. The compressor usually kicks in during the seating process. I might be wrong here, somebody better try it.

I forgot to mention that there’s another very cool air source alternative. A CO2 tank. It’s basically a small (10-15 liters) CO2 welding tank or a scuba diving tank, which can be filled with CO2 to almost 2000 PSI from any welding shop. The welding regulator (usually comes with the tank) allows the air to be released slowly to fill up the tires and can easily reseat the a tire. In fact if the tank is full, it’s more powerful and faster than my engine driven compressor.

Why CO2? Because it compresses much better than any other gas, so you can put much more air inside that small tank at 2000 PSI. A 15 liters tank can easily inflates 40 tires. Yes, that’s 40 tires . And it’s no bigger than a scuba tank, you just toss it on the roof rack (not inside in case of a leak) and forget about it.

All you need is to get a regular welding tank with it regulator and get an air chuck fitting for it to fill the tires.

I hope I’ve explained how it works well. Feel free to ask me for more info if you want to make one.

A company in the US sells them ready made for off roaders. www.PowerTank.com . Check their site for more info, but you can make you own much cheaper.


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A.B.
www.ShortWheelbase.com

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A.B.
OasisPhoto.com – Images from the Magical Sahara.

Errr... at over 300 USD a throw the PowerTank seemes a bit OTT. For that money an engine drive compressor can possily fill 40 thousand tyres (cost of fuel to run the engine).

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Roman (UK)
www.polandrover.com

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Roman (UK)

Do you get a gold star if your topic goes over 50 replies??!!

Sam.

or a free T-Shirt perhaps ???

Roman, it is OTT, but you can make your own for less than a 100$ in used parts

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A.B.
www.ShortWheelbase.com

[This message has been edited by A.B. (edited 11 June 2002).]

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A.B.
OasisPhoto.com – Images from the Magical Sahara.

Sure CO2 is great giving you lots of gas very quickly, but what happens when it is empty? How many places in the middle of the Sahara have the facilities to top up a CO2 tank?

Great if you are just off roading for the weekend and you can have it refilled on Monday morning, but for expedition stuff forget it.

Fitting an air con pump and a tank (the really important bit) will not cost a lot if you use secondhand bits less than £200 anyway.

I do agree with you that a compressor is better (engine driven, not electric) but actually you can refill your CO2 tank almost anywhere in the world.

Maybe I neglected to mention this in my previous post; the tank you should get is a regular CO2 welding tank. They come in sizes that range from a small fire extinguisher bottle to huge tanks (1.5 meters). They all have the same manifold and use the same regulators and are all pressurized to 2000 PSI. As long as you didn’t change the tank fittings (and why would you), you’ll be able to fill it anywhere in the world that has a welding shop. The welding shop itself might not be able to fill it for you but at least they will point you to where they fill their own CO2 tanks. It usually takes 24 hours in most parts of the world to refill and test your tank.

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A.B.
www.ShortWheelbase.com

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A.B.
OasisPhoto.com – Images from the Magical Sahara.

[QUOTE ...the air compressor available through this website... QUOTE]

Hi
I'm new to this site and cannot find the above mentioned air compressor...can anyone give me the direct link?
Thanks