Onboard Air...

Hi all,

I'm slowly sourcing parts for an onboard air system with bits of information gathered here, there and everywhere (surprisingly hard to find an actual parts list with links to what you need etc..). I have an almost new sanden compressor from a puma a/c that i'm going to use (not got it in my hand yet but hoping it will fit with not a lot of hassle....)

I was about to go down the local scrappy to find an air- brake tank when I remembered an old 240v garage type air compressor I have at work that is broken. So, i'm going to pinch the 25 litre tank from that.



Can I use the the gubbins too? Literally, re-use the manifold (safety valve, pressure switch, tank gauge, pressure regulator) and the non-return valve already in the tank?

It's this one... it's broken in that no power to it (messing pump knackered) https://www.drapertools.com/products/manuals/03321ins.pdf

Cheers in advance,

Ben

huffhuff said:

Hi all,

I'm slowly sourcing parts for an onboard air system with bits of information gathered here, there and everywhere (surprisingly hard to find an actual parts list with links to what you need etc..). I have an almost new sanden compressor from a puma a/c that i'm going to use (not got it in my hand yet but hoping it will fit with not a lot of hassle....)

I was about to go down the local scrappy to find an air- brake tank when I remembered an old 240v garage type air compressor I have at work that is broken. So, i'm going to pinch the 25 litre tank from that.

Can I use the the gubbins too? Literally, re-use the manifold (safety valve, pressure switch, tank gauge, pressure regulator) and the non-return valve already in the tank?

It's this one... it's broken in that no power to it (messing pump knackered) https://www.drapertools.com/products/manuals/03321ins.pdf

Cheers in advance,

Ben

Click to expand...

A great idea, I'd have never thought of that, I have onboard air on my Disco courtesy of ARB, normally an over-priced compressor but it was a gift from a guy who had no more use for it on his Tojo.
So long as you have the space to fit said "gubbins", tucked up beneath the vehicle it should work a treat, the pressure switch can be used to control the Sanden a/c compressor clutch, you need some type of filter system on the compressor suction, perhaps trunk a suction hose from compressor to the engine air filter body, a high pressure hose compressor discharge to the tank, the rest of the bits, manifold, guage, relief valve, regulator, pressure switch etc can stay as originally fitted to the reservoir, the reservoir minus the compressor/electric motor unit should be pretty light weight, use a self seal bayonet fitting that you can simply plug a hose into to service all around the vehicle.
The only possible pitfall with using A/C compressors for air is that moisture in the air is an issue that can bugger the reed type valves and also the lubrication of internal parts means you need to put a bit of mineral oil into the suction line every now and then depending on use.

Thanks @Gazbo.

Just gone and dug it out of the barn... The tank pressure gauge is smashed so probably not working - not end of the world I guess. The pressure switch has the mains cable going in and then out again to the compressor so will take that to bits to see if it's still a viable option (I imagine it probably is 12/24v when I get in there)...

I was going to use something like this for lubrication... http://www.screwfix.com/p/air-tool-mini-in-line-oiler/4389h

Mini K&N type filter for the air like this http://www.ebay.co.uk/itm/New-Breat...hash=item43b12cc198:m:mP79wZUpXdLBjPpo8w-PSMA

Then an oil separator the other end like this.... http://www.ebay.co.uk/itm/Sealey-IL...hash=item53e9beeda6:m:mcFwD85mm6eCqYKKlCj_adA

Could I fit the manifold away from the tank? As in, tank under the car in 'usual' space but piped to the manifold under the bonnet? It doesn't have to be right there surely (can't see why it would)

Cheers

There are a couple of threads on here doing this. One using a fire extinguisher tank.

The Mad Hat Man said:

There are a couple of threads on here doing this. One using a fire extinguisher tank.

Click to expand...

I am in the process of doing this and using the original A/C pump and a small fire extinguisher as my tank. I am following the write up found here (link) (apologies for linking another forum, please remove if not allowed) although until I find a suitable cooling coil will be skipping that. I have all of the parts now apart from the pressure control switch as I have still not found a suitable one at a sensible price. Starting with a compressor already would give you all of the parts needed and reading other threads the mains switches work fine at 12V.

Be wary of using an A/C compressor - they are designed to have lubricant running in a closed system.

Look at this on eBay
90-110 PSI Heavy Duty Air Pressure Control Switch Train Horn Compressor 12V 3.5A

I used my T-maxx HD compressor, took it apart, fitted it in the channel behind the Landy seats, used a manifold for the manifold to suit the Diff lock etc. I also fitted a quick coupler for the airline to blow the tyres up. I'd like a small air reservoir but really haven't found a need enough for me to buy one, the compressor works well enough to fill the tyres within a couple of minutes, time for a comfort break ..

dag019 said:

I am in the process of doing this and using the original A/C pump and a small fire extinguisher as my tank. I am following the write up found here (link) (apologies for linking another forum, please remove if not allowed) although until I find a suitable cooling coil will be skipping that. I have all of the parts now apart from the pressure control switch as I have still not found a suitable one at a sensible price. Starting with a compressor already would give you all of the parts needed and reading other threads the mains switches work fine at 12V.

Click to expand...

Could you use some coiled up copper pipe? I didn't even think of a cooling loop but will probably use copper (as there is a shed load at work)

I also recently picked up a 'britpart' heavy duty twin pump compressor (12v) so will probably use that for testing before I get around to picking up the sanden

I've read about people just carrying drive cyclinders and a regulator to inflate tyres and when it drops from 232 or 300 bar just taking it back to the drive centre and getting it refilled.

Or if you want to add a compressor and small tank, soda stream cyclinders might be an option if space is tight.

Mcclegend said:

Or if you want to add a compressor and small tank, soda stream cyclinders might be an option if space is tight.

Click to expand...

That is why I'm using a fire extinguisher, it is only an old 2kg powder one so not very big at all but still large enough to act as a volume buffer in the pressure system. It will also allow everything to be mounted under the bonnet.

I've got a 90 so limited on space underneath. I think the 25 litre tank might be a tad too big. Luckily I found another workshop type compressor in the shed at home. I think I picked it up from my grandads ages ago, originally bought in 2002! This one has a much smaller tank

So now I have two lots of manifold bits and bobs to do some jiggery pokery with

Hi all,

I've picked up the Sanden 4399 compressor. There are no pipes with it and they don't look standard.

I've tried googling but nothing really coming up. What can I use to connect to the compressor? Anything 'off the shelf'?

Cheers...

huffhuff said:

Hi all,

I've picked up the Sanden 4399 compressor. There are no pipes with it and they don't look standard.

I've tried googling but nothing really coming up. What can I use to connect to the compressor? Anything 'off the shelf'?

Cheers...

View attachment 128280

Click to expand...

tiz a speshul fitting, with central M10-1.25 clamp bolt through a plate. both pipes are fitted to the plate.

The Mad Hat Man said:

tiz a speshul fitting, with central M10-125 clamp bolt through a plate. both pipes are fitted to the plate.

Click to expand...

Damn it. Thank you

I'll do some googling and see if I can come up with a part number or such... (holding no hope there..)

no need



you do realise its an aircon compressor and is supposed to be used on a sealed sysem?

A/C compressors are not suitable for compressing air. They work from a swash plate and rely on system pressure to return the pistons and need upper cylinder lubricant. That is why they will not engage with low system pressure or they will be destroyed.

Thanks guys,

Are you saying I got the wrong sanden compressor and that all the other people that have successfully done this with what I thought was an a/c compressor are using something else?

Ta

I am saying that air con compressors are not the best option, and if buying one, I wouldn't choose it.

Can I ask what pressure your going to set your cut off switch to, max for the tank or something else?

The Mad Hat Man said:

I am saying that air con compressors are not the best option, and if buying one, I wouldn't choose it.

Click to expand...

I see what you are saying. I picked up the compressor relatively cheap and if that fails or doesn't work as expected, I also have a britpart "heavy duty" double pump that can take its place. I just like the space-saving side of this setup, plus engine is doing the work and the pump can run for longer periods of time (plus i'm sure it's a higher CFM).