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G'day all,

Does anyone know/has anyone converted an airsuspension compressor into a unit used for pumping up tyres etc? Biggest question if it works is: How effective is it?

And the EJ liberty (early ones) fit under the guard of the L series in the same spot doesn't it?

I'm thinking of getting one setup for when I need to pump up tyres after deflating for 4wd'n, this would be a great little setup to use as it will be mounted in an unused space that I wouldn't be using otherwise.

If you've done this could you let me in on some details?

Cheers

Bennie

I do recall someone on here doing it, its in passenger's side guard, its a quite slow compressor i think. You'll find them in Gen 1 Liberty before 94.
Cheers
AP

Cheers AP - I knew that's where they come from and where they mounted. The L series units are very hard to find but the Liberty ones are starting to show up in the parts yards...

Cheers

Bennie

i can recall people saying its a waste of time using it for anything other than it was designed for. if you dont have aircon, a aircon compressor is a better option. phiz and his brother would be the ones to chat to

Thanks Shuffbag, not really good news...
I'll have my AC sorted this year hopefully. I can't see there being any room for another compressor, even though I've got one sitting in the shed.

Cheers

Bennie

ha i never got around to switching aircon with my conversion, lazyness i guess.

would be good if you could get this working, i would like to know how well (slow or not) it works.

good luck

Hey Bennie, IMO I say the storage tank would be too small. If you could use the sensors from the tank and make a larger one then you'll have a better system but not the greatest as the pump is very slow. I think and I'm going to use this in my offroader is a small A/C pump from a small car (cheap from the wreckers) and have this running off the fan belt and a toggle switch setup to bring in the compressor's clutch.

RSR 555 wrote:Hey Bennie, IMO I say the storage tank would be too small. If you could use the sensors from the tank and make a larger one then you'll have a better system but not the greatest as the pump is very slow. I think and I'm going to use this in my offroader is a small A/C pump from a small car (cheap from the wreckers) and have this running off the fan belt and a toggle switch setup to bring in the compressor's clutch.

Thanks RSR,

I might bin that idea and start looking at mounting a second AC pump somewhere...

Cheers

Bennie

Giving up so soon?

An excellent idea bennie! We can try on my car first seeing as it's already there and not being used

It takes about 15 seconds to pump up four shocks enough to raise by an inch. I'd have to check the shop manual to see what the overall volume is, maybe from that we can guess at a flow rate?

The air lines are quite small, about the size of a pen insert - you might want to look at modding the pump's outlet to accommodate a larger hose and thus remove at least one restriction. Then you'd just have the small reservoir to figure out...

The original on/off switch is based on a sensor on the strut assembly, so you'd need figure out the wiring anew. How cool would it be if you could wire it into a pressure gauge?! Set the desired pressure and off it goes!

I think you'd first want to look at the flow rates to see if you can get a reasonable amount of air out... It'd have to put out a bit of pressure to pump up a fully loaded wagon with five people plus camping gear...

Definitely worth an experiment!

Well Bennie that's up to you but maybe you could find the guy that AP is talking about. He may have some insight into what he achieved? I'm also interested to find out

That could be the go Owen! You seem to know more about it which is a good start. I said I'd look else where as I'd have to shell out for the unit to find out if it would work or not - something I'm not really keen on.

RSR, I read a lot of this forum and all I can recall is someone wanting to change the air pick up on their unit but ended up doing nothing as the factory setup was apparently the best way to do it.

I'll keep it in the back of my head anyway. Maybe Owen could do a bit of playing around and see what he finds.

Cheers

Bennie

El_Freddo wrote: Maybe Owen could do a bit of playing around and see what he finds.

Teehehe, could be a while... I still have to make your and Venom's spare wheel carriers yet

ScubyRoo wrote:Teehehe, could be a while... I still have to make your and Venom's spare wheel carriers yet

I was taking the piss when I said that! You should know that you open yourself up to a bit of sarcasim when you mention welding smaller things to get some skills!

I probabily won't need it. I've got my uncle sorted to get one put together. It'll have a wheel carrier and a jerry can holder too. Hopefully you will be able to check it out at the next 4wd outing for some ideas

We could talk more about the air suspension then.

Cheers

Bennie

Sorry to hijack the topic -

Something i found about 2 weeks ago while cleaning out my father in laws garage - previous owners left something behind in the ceiling (strange place!) was a strange looking 4 metre hose, I wondered what it was, it was an air hose but had a "V" tappered thread head and a valve that goes on your tyre's valve, then i figured it out is that you put in spark plug hole and start the engine (would be running rough!) and use the compression air as air compressor!

I would say its about 20 plus years old...
I would be strongly against it (specially for Subaru due boxer engine layout)!
Cheers
AP

El_Freddo wrote:I was taking the piss when I said that!

As was I

ScubyRoo wrote:As was I

I should have known better!

Cheers

Bennie

Was in the suspension section for repairs today, and came accross the air pump section... From the shop manual found on this site...

'6. Drier

'The drier dries air which folows through it to athe air tank or each air spring, with silica gel, in order to prevent freezing of water in the air pipe. The silica gel is refreshed by dry air during air discharge.

'A residual pressure valve is provided so that the diaphragm can always be held in the expanded state, hence a residual pressure of 98 kPa (1kg/cm2, 14psi) remains in the air chamber even after air discharge operation is completed.'

This may speed up the 'spooling' time of the compressor? Nice dry air in the tires

'7. Air Tank'

'Pressure switch and solenoid valve for air charge are incorporated in the airtank. The tank is filled with compressed air of 755 to 941 Kpa (7.7 to 9.6kgcm2, 109-137 psi).

'The air tank contains air [2,500cm3 (2500cc, 152.55cu in)] to raise the vehicle or maintain it at a constant level under various loads by shifting the pressure switch from the "normal" to the "high" position.'

Sounds like plenty of pressure can be built up, but i have no idea how to calculate what volumes would be needed. How much air is in an offroad tire???

'8. Pressure Switch

'If the pressure in the air tank rises, the pressure sensitive disc pushes the guide pin up to open the moving contact, and the switch is opened. When the presure drops, the switch is closed.'

I wonder how quickly it can replenish the tank and how well it can maintain that pressure...

guys its been tried before and was pretty useless.

the pump is a low volume, high pressure pump.

you want a high volume, low pressure pump for quickly inflating tyres.

Grab a good quality aftermarket pump and mount it in the space behind the guard.

or a good aftermarket aircompressor fits nicely in the engine bay where the spare normally sits.

looked at an endless air setup benny? aircon compressor into a smallish tank. Inflates tyres very quickly and efficiently. Currently looking into it on my patrol.

alex

Keffa wrote:looked at an endless air setup benny? aircon compressor into a smallish tank. Inflates tyres very quickly and efficiently. Currently looking into it on my patrol.

Thought about it. Room is the issue as I want my AC! I'll have to look at it on the weekend. Getting a lift kit sorted might help with room, that could be something to consider too.

Cheers

Bennie