Airmaster 50

[Bryan Williams]

Hi thanks for accepting me on the forum.Im a DIY bodger , I've got a little Clark arc welder which I'm quite proficient with ,made a few things,r+r bed for my camper, stainless side exhaust,gates,ect. I just bought a second hand airmaster compressor, it's got a couple of issues.Its a 2hp 50ltr .
The pipe going into the pressure switch is faulty it's come out and the little plastic fork clip that holds it in is broken. There are spare pressure switch assemblies but they have different pressure autocut out psi's.Any idea which I should get?. Also the pressure valve under the tank is hissing , how do I reset it?
Cheers, Bryan.

 

[pedrobedro]

The pipe going into the pressure switch is faulty it's come out and the little plastic fork clip that holds it in is broken. There are spare pressure switch assemblies but they have different pressure autocut out psi's.Any idea which I should get?. Also the pressure valve under the tank is hissing , how do I reset it?
Cheers, Bryan.

The pressure cut off is adjustable in most replacements but the difference between cut off and kick in is fixed on the cheaper ones. Clarke sell the Airmaster switch. The pressure valve under the tank is most likely not a valve but the drain off. It might need tightening or possibly a new O ring.

 

[rtbcomp]

Welcome to the forum.

The drain was probably left open by the previous owner.

 

[slim_boy_fat]

Hi thanks for accepting me on the forum. Im a DIY bodger

Welcome to the forum, fella Don't let your 'status' bother you, many of us here are but they're a great crowd who are always willing to help/guide/advise

 

[Bryan Williams]

Cheers guys,went to Machine mart today with the pressure switch,but the thick plottens, the pipe that goes into the bottom is different on mine than the replacement.On mine it just sits in and is held in place by a plastic clip that looks like a miniature tuning fork, one of the legs has snapped off so it's falling out.You might see in the pic the slot on the end of the pipe that it fits.The new design is the same as the other end, a nut.So I need the pipe with the right connection nut on both ends, they don't supply this, I have to phone thier parts dept Monday. I am going to play around trying to make a clip out of something to see if I can get the pipe to hold in, thing is I don't know there's a seal or o ring missing.Its not high pressure,it has two pin prick size holes, one in the end, one in the end side.
Stuff I didn't mention first time.. the motor impeller was smashed, I managed to get what was left off , it's held on with a circlip,in my work we have a lot of old motors off bifurcated fans , I'm hoping one of the impellers will swap over. I'm hoping it's not been running with out the impeller too long... I've had it up to 60lbs Pressure before the leaking pipe(and the undone drain that I wasn't aware of )beat the pump.The pump felt quite hot while doing this. I probably bought a pig.. we'll see.

 

[rtbcomp]

You should be OK making a new fork, there's no seal. The plunger in the top of the valve is pressed in (or allowed to pop out, I can't remeber which) when the tank is up to pressure. The fitting with the nut is probably a compression fitting, although these are usually used with copper unloading pipes. The plastic ones like yours usually have a push-fit connection.

 

[Bryan Williams]

You should be OK making a new fork, there's no seal. The plunger in the top of the valve is pressed in (or allowed to pop out, I can't remeber which) when the tank is up to pressure. The fitting with the nut is probably a compression fitting, although these are usually used with copper unloading pipes. The plastic ones like yours usually have a push-fit connection.

 

[Bryan Williams]

I made a fork and it went in flush and snug, but I fired it up and it still leaked a lot the pump was just keeping up and emptied quickly when turned off. I sprayed soapy water round it and it's definitely that weeping

 

[Bryan Williams]

I made a fork and it went in flush and snug, but I fired it up and it still leaked a lot the pump was just keeping up and emptied quickly when turned off. I sprayed soapy water round it and it's definitely that weeping

I made a fork and it went in flush and snug, but I fired it up and it still leaked a lot the pump was just keeping up and emptied quickly when turned off. I sprayed soapy water round it and it's definitely that weeping

I was told by the machine mart guys that the pressure it turns off at can be adjusted by the big nut on top.wondering whether it's been played around with and it's relieving air straight away?

 

[Bryan Williams]

Fair enough, can't do anything till Monday, guess it's a new pressure switch and pipe. What's your opinion on the motor not having an impeller? Is it critical or can it be be run to test it? The pipe coming out of the top got hot quick.

 

[rtbcomp]

Don't change the pressure switch just yet. As @pdg says it's more likely to be the non-return valve (NRV), this is the bit that screws into the tank and is fitted on the end of the pipe (the delivery pipe) that comes from the pump.

The valve on the pressure switch (the unloading valve) opens when the pressure switch turns off, this empties the delivery pipe, but if the NRV is leaking back into the delivery pipe it will try to empty the tank as well. Often the NRV can be fixed by cleaning it, or replacing the rubber bit (the pastille) inside.

Whatever you do, don't undo the NRV when there is air in the tank, and bear in mind there is a spring inside it.

View media item 1686
You don't need to remove the NRV, just undo the end cap.

 

[Bryan Williams]

Don't change the pressure switch just yet. As @pdg says it's more likely to be the non-return valve (NRV), this is the bit that screws into the tank and is fitted on the end of the pipe (the delivery pipe) that comes from the pump.

The valve on the pressure switch (the unloading valve) opens when the pressure switch turns off, this empties the delivery pipe, but if the NRV is leaking back into the delivery pipe it will try to empty the tank as well. Often the NRV can be fixed by cleaning it, or replacing the rubber bit (the pastille) inside.

Whatever you do, don't undo the NRV when there is air in the tank, and bear in mind there is a spring inside it.

View media item 1686
You don't need to remove the NRV, just undo the end cap.

Brill, something else to mess with, I coincidentally read up on cleaning this but didn't make the connection. Thanks for the safety tips, I am a bit bit paranoid about safety when I don't know what I'm doing so I will double check all that.
Thanks again everyone for the help.

 

[Bryan Williams]

Haven't had chance to check/clean the never yet , been ill ,so I thought I'd phone machine mart parts to check availability of a pipe from the valve to the pressure switch in case I have to upgrade both.What a bunch of jokers, first off I explained my problem,he gave me price for the original pressure switch.When I told him that if I did decide to replace the PS I would put the later one on as it is a better design, so I would need the pipe to match.He said he couldn't give out information on modifying equipment and refused to give me the part number of the pipe. I am hoping that cleaning the nrv will do the trick but if I decide on replacing stuff I'll either go like for like or persuade them to send me a pipe.Basically what he was saying is that if you wanted to build your own custom compressor from scratch you best go elsewhere.

 

[Bryan Williams]

Haven't had chance to check/clean the never yet , been ill ,so I thought I'd phone machine mart parts to check availability of a pipe from the valve to the pressure switch in case I have to upgrade both.What a bunch of jokers, first off I explained my problem,he gave me price for the original pressure switch.When I told him that if I did decide to replace the PS I would put the later one on as it is a better design, so I would need the pipe to match.He said he couldn't give out information on modifying equipment and refused to give me the part number of the pipe. I am hoping that cleaning the nrv will do the trick but if I decide on replacing stuff I'll either go like for like or persuade them to send me a pipe.Basically what he was saying is that if you wanted to build your own custom compressor from scratch you best go elsewhere.

Ha 'never' meant nrv

 

[rtbcomp]

That pipe's standard stuff, if you get stuck post close-up some photos of where each end fits. A local compressor specialist should be able to help out.

 

[Bryan Williams]

That pipe's standard stuff, if you get stuck post close-up some photos of where each end fits. A local compressor specialist should be able to help out.

Cheers, learning as I go along on this,watched so many youtube redneck compressor repairs today feel like ripping the fridge apart for bits.

 

[rtbcomp]

^^ People ( or person at least ) has done dafter things.

https://forums.lr4x4.com/topic/9710-fridge-compressors/

 

[normspanners]

crowd who are always willing to help/guide/advise/ missing

You forgot------- the bit about----- extracting the urine!!

 

[slim_boy_fat]

You forgot------- the bit about----- extracting the urine!!

You'll put the poor chap off

He's bound to fall for the link to the mankini pic sooner or later...........

 

[normspanners]

OH NO---- I'd forgot about that