Identify parts on an Aeraspray compressor - Birmingham UK

by Liam
(Manchester UK)

Aeraspray compressor

Aeraspray compressor

Aeraspray compressor
Aeraspray air compressor
Aeraspray compressor plate
Aeraspray compressor information


I have just bought this old compressor,
which has an Aeraspray pump and a Newman motor.

It doesn't have a cut-off switch,
so from empty it chugs up to 95 psi,
then the release valve vents it back to 75psi
(The release valve is at the bottom left,
of the silver grill thing near the bottom right of the compressor)

You can see it in action , and the release valve venting, at

It won't start pumping again until the pressure is zero,as the piston pressure unloader valve,
is either not working , or not present?

I can tell there's pressure in the cylinder , as it is hard to turn the wheel when the tank is half up to pressure.

Could anyone please tell me what the pipe from the top of the piston to the silver fin thing at the bottom is?

and.. On the top left of the silver fin thing there seems to be a heavier release valve (A).

and.. what the silver fin thing (B) is too...

At the bottom of the silver fin thing , there are two outlets
one has the release valve, and the other has a pin/tapered point bolt inside.

Many Thanks

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Sep 04, 2016
That is great, another Aeraspray!
by: James

Hi Liam. I am unable to assist you with your query but I am definitely interested to see another Aeraspray compressor pump.
I see that the flywheel pullies are characteristic of these old Brummie beauties.
I have a V twin Aeraspray that I am wanting to know more about.
I've just this minute posted my enquiry with links to the Photobucket images of the old girl.
I haven't run it but she does snort and blow when rotated so there is hope of life in her yet ;-)

Oct 20, 2015
Thanks Roger
by: Liam

Thanks Roger and all..
I have ditched the bits that I didn't understand.
Luckily too... as some pipes were blocked solid.

I am going to let it run when I need volume...
as it trips out at 90psi, which is plenty for what I need. (It is linked up to 200litre tanks or 50 gallons)

When my noisy direct drive finally croaks,
I will grab the cut off switch ,
and unloader nut (which goes into the tank) from it.

Atm, I rarely use it in ernest... it's more for the novelty and blowing dust etc..

Here's the latest picure

the plugin air gauge is a temporary thing... I am waiting for a tee from ebay, to set it in-situ.

Cheers for all the replies and the help :)
ps Doug, the fin thing was empty... as you say, it was indeed deigned to cool the air...cheers

Oct 19, 2015
Parking Lot Sprayer
by: Roger

Looks to me like a portable parking lot sprayer with a constant run unloader.

The big brass contraption is supposed to pop and send an air signal to the unloader tower on the cylinder head to hold open the inlet valve so the pump can free wheel while the motor continues to run.

This is helpful since such a small tank will drain down quickly, causing many stop/start cycles which would be hard on the motor.

I am thinking this was originally a gas drive unit, and the unloader also had a throttle control signal coming from it to throttle back the gas motor when the tank had filled.

In this setup, you would absolutely need an unloader to the head, or the motor would stall when it throttled back.

The nuts on the brass valve are used to set cutout pressure, and the range within which the compressor would cycle on/off while running.

If it were my compressor, I would toss that and install a brass check valve with a bleed port between the pump and the tank, and tie it into a pressure switch with a blowdown needle valve on the side to switch the motor on and off. When the compressor cuts out, the needle valve bleeds of the air between the pump and the check valve so it has a loadless start and doesn't trip any breakers.

Put a decent safety relief valve on the tank and you should be good to go.

If this is a single stage machine, in which air goes from the inlet cylinder straight to full tank pressure, do not set it for more than 120-psi, as single stage compressors get very inefficient and hot running any higher than about that pressure.

Oct 18, 2015
more details and closeups
by: Liam


I've added some close up pictures..

On the silver fin thing, there are two outlets at the bottom.. one on the left and one on the right.

I'm also not sure if the gasket added, is right?

Cheers All

Oct 18, 2015
It's a Mystery, it's a mystery...
by: Liam

lol, yup... what is said is not what I meant ..
the A should be B :)

It's a bit of a mystery...
..but that may be, because the release valve is kicking in too early. (about 90psi atm. I think the spring has weakened as it continually vents when running. Since I have no idea what bar the tank id , I have played safe and ordered an 8 bar 1/4 bsp release valve...99p! including delivery , all the way from China !)

The silver thing "A" is on the output from the tank, after the air is already in the tank.

Today, it is doing something different. It is not getting beyond 90psi..since the release valve is slightly open, causing the pressure not to build beyond that.

Nothing's unloading atm.. I have to either wait for the faulty valve to lose the air.... or manually drain the tank,before starting.

yup, the video works fine for me..
maybe a shorturl may help?

I may just leave as is... and get a plastic pressure switch and unloader valve in the future..

Many Thanks for the reply

Oct 17, 2015
by: Doug in

I think maybe what you say is not what you meant, so far as descriptions / letter IDs.

But "A" looks like a cooler to condense moisture before it gets to the tank.

I think "B" may be a regulator and unloader, where the motor runs always, but the compressor isn't working, but starts working when pressure drops.

Can't see all the plumbing, so maybe that's all wrong, but that's what it looks like.

I can't get the video to play - is it working for you?

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