Hi, Try draining the tank out first then start digging deeper. Regards.

.

That would depend on the size of your milling machine and how tall you are.

Nick

Is there an automatic unloader valve fitted?

Some years ago I had an Atlas Copco KE2 Vee twin compressor with unloader valves in both cylinder heads fed by a spring loaded pressure release valve fitted to the tank. When the tank got up to pressure this valve would open feeding air to the unloader valves opening them so no pressure could build up in the cylinders. This set-up was intended to be used if you were using lots of air letting the compressor run continuously rather than lots of short start – stop cycles. Very important on a single phase motor as these can only cope with a limited number of start – stop cycles per hour without risking burning out the start winding. My valve was adjustable so you could set the operating pressure.

Had to clean up the valve innards a two or three times when contamination stopped it sealing properly. Air leakage was sufficient to open the unloaders before it got up to pressure. Small bleed hole in the system to let pressure out so the unloaders would close once tank pressure had dropped enough to close the main valve. This would block, or partially block, on a fairly regular basis driving the system nuts. I suspect my main valve never quite sealed properly so there was always a small leak through the system which probably didn't help.

On a small compressor the pressure release valve in the starter can leak enough to stop it coming up to pressure. In my experience this is only applies to compressors with less than 5 cu ft / min delivery.

Clive.

As Roger says the ordinary pressure switches are fairly standard. Generally the main differences are in how the manifold pressure release valve works and connects. I've seen at least 4 versions of thread, connection and seal style. Most annoying when the olive or thread on the pipe connector won't fit. Especially if the pipe isn't long enough to cut short and re-make the connection without major mucking about. Even worse when the basic switch comes without the nut and olive, just a bare threaded stub in the wrong style. These days I like 6 mm push fits for this sort of thing. OK you have to stock some pipe and adapters but you know that you can make anything fit. As a Range Rover P38 pilot I've got stock of pipe and adapters anyway!

Surprised by Rogers diaphragm failures. Most of the troubles I see are manifold pressure release valve related. Cheapies generally being less durable than the OEM quality ones. That said its arguable that £6 a pop every couple or three years for a new cheapie is abetter bargain than £60 for oem lasting 8 to 10 years. At least with a cheapie you can afford two so have one in stock for immediate replacement. Its what I shall do when I get round to fixing the leaky one in my suitcase compressor.

Clive

It is more usually a valve problem, than rings, where compressors are concerned, I think.

only to be told that this was not an Ingorsoll Rand model

That looks very similar to a Clarke branded compressor we had at my last employment – might be worth a look on the Machine Mart site to see if there is currently one like that offered. MM do supply parts, but at a price and in their own good time !

Nigel B

Ingersoll-Rand Euro Compressor is the economy range. Was told bought in and badged. By IR standards its a cheap, disposable, air pump not worth overhauling. Italian made according to a pal who lifted a broken pump from the firms skip after they slapped a new pump on theirs. He said new pump was about £100 so not worth their while fiddling. E-Bay says £90 to £140 for similar looking in a couple or three sizes these days.

Search for Euro Compressor turns up some similar looking pumps. Fiac and SIP do twins that look the same and list spares.

Valve block trouble sounds likely. Hopefully just valves dirty and not sealing. Unbolt, clean up and verify that they seat. Hour or so first time through. valves said to be prone to twisting and edge wear which is more of a problem as the thin leaves are virtually impossible to re-work.

Clive.