Any Air Compresser guru's? Lol

[Chris_Pallet]

I have a air compressor that is about to get thrown out! Lol..
Just wondering if anyone has come across this problem

- Model
Airmaster Tiger 8/35
- Problem
Reaches 8bar then releases air till 6bar then just keeps cycling the same process untill the thermal switch cuts and stops it.
- so far
I've replaced the capacitor, parts of the pressure release valve (due to ebay knock off), cleaned head and piston valve, checked for leaks, none found.
It releases air from the small pipe into pressure release valve not the safety release valve.

I know there not expensive I just didn't mind tinkering about with it

But at this rate its going to be like 'Triggers Broom' hahahaha


Any advice or experience will be greatly appreciated. Thank you kindly.

 

[okeydokey]

I think this is a Machine Mart compressor they might have a helpline? you will be able to get a manual online.
Have you drained any water out via the drain valve (when the tank is air empty

 

[HappyHacker]

When the compressor reaches its max pressure the pressure switch turns the motor off and releases the pressure in the compressor so that it does not restart under load when it detects the minimum pressure has been reached. Is it this valve that is not working?

 

[Chris_Pallet]

When the compressor reaches its max pressure the pressure switch turns the motor off and releases the pressure in the compressor so that it does not restart under load when it detects the minimum pressure has been reached. Is it this valve that is not working?

Yes exactly this, the air releases from the small pipe under the pressure switch, where they're wires go in.

It's almost like it doesn't know to turn itself off, it goes 8bar, rather than stop it carries on till 10bar then releases till 6bar then repeats the whole process 3 or 4 times tull the thermal switch trips.

 

[pgrbff]

Same thing happened to me. Check small diameter pipe is seated correctly and if not replace pressure switch. I think they are fairly universal.

 

[flh801978]

Its the nonreturn valve leaking….where the small pipe goes to on the tank is a rubber washer with a spring pushing it down onto a seat…it leaking and letting the tank air go through the pressure switch…empty the tank and take this alve apart…its easy to see what’s wrong

 

[Chris_Pallet]

Thank you kindly for your assistance.

So I've
- Replaced capacitor
- Replaced full pressure valve assembly
- checked piston seals and re tightened head
- checked for leaks
- opened drain port for any water
- checked oil levels


Still the thermal switch kicks in as it tries to recycle itself.

My only opinion is the actual motor is shot and overheating causing issues?

So I've had enough, before it becomes triggers broom. I'm going to sell it on here for someone else to tinker with (and probably fix within mins lol)

Gonna treat myself to a new compressor, thicknesser Planer and maybe a chip extraction if needed.
I might be lucky and someone will sell me the lot lol..

Thanks again for all your advice, such a great forum.

 

[flh801978]

Have you looked at the non return valve as i suggested?

from the start the tank is empty...
the motor starts and is filling the tank...
it pushes the air into the tank via a non return valve...
when the pressure switch senses 10 bar ( 150psi) the pressure switch opens and stops the motor...
in the pressure switch is another valve which bleeds off the high pressure air still in the pump and pipes...so when the air pressure in the tank drops the motor can restart under no load...(this is the small nylon pipe)
when the motor restarts the valve in the pressure switch closes to allow the pressure to build up...
If the non return valve is leaking ( which they do often) when the motor turns off the valve in the pressure switch opens to release the high pressure in the pump and pipes...the air from the tank goes past the non return valve ( as its leaking) and quickley emptys the tank so the pressure drops and causes the motor to cycle too often leading to overheating and failure.
when the motor stops and air is in the tank there should be no leaks or sounds of air escaping if there is its the non return valve leaking via the small nylon pipe to the pressure switch.
theres usually a largish 19mm hex head on the non return valve...a big pipe coming from the pump and a small pipe going to the pressure switch.
with the tank empty undo the 19mm hex and theres a spring and a rubber washer which will have perished or hopefully dirty.
DONT undo this nut if theres air in the tank... otherise you have a largeish nut missile

 

[clogs]

the non return valve ...(19mm hex nut, again only access this valve when the tank is EMPTY)) ends up with rust flakes on the seat.....have cleaned a valve several time before it stays clean.....the valve is often just a plastic washer on the cheapies and st/steel on the up market comps.....either way it does the same job....
Cr@p from the tank and steel pipes tends to find it's way into the valve occ.....
ALSO the main on off /switch pressure valve gets tired.....they can be had from about £12....I get mine from eBay...they are all made in China and never had a bad one.....I have around 6 compressors in different places and these st/strt p/valves are cheap enough to have a couple of spares.....my largest comp Atlas Cop Co is around 7HPx 3phase and still the stop/srt p/valve was less than £25....

 

[Chris_Pallet]

Well I owe you all a beer......

After all your advice -
I took the non return valve off again, cleaned it to an inch of its life, pulled the spring a bit better. Plus I think the rubber grommet was in wrong way as there was a nibbly bit on it which I think was getting stuck in spring, instantly the rubber grommet was pushing out better.

Anyways done this, and the compresser stopped at 8 bar and didn't kick in till I expelled the air till 5bar.
No over heating
No air leaks
Works perfectly now.

Honestly please let me know next time your in weatherspoons and your table number and I'll ping you a beer.

You've saved my sanity and also a few quid!

Thanks again, really appreciate it...