Air compressers

Hi,

Does anyone out there know about air compressors ?

My unit Ingorsol Rand 150 lt will only build up pressure to about half way and go no further,just keeps running. I have checked for leaks,found none,and the belt is tight,no slack. Any ideas ?

On another subject,what is a good height for a mill table?,I have mine set at 3ft,but I find it a bit low when using the rotary table [yes,I do still use it from time to time ! ]

In no particular order......based on a piston type compressor

Worn pistion rings / and or bore(s)

Inlet/exhaust valve (s) sticking/not seating properly

Blocked inlet filter

None-return valve not seatting properly

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

Thanks,Guys,

Will start checking those points.

.

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

Nick

If it is a two stage pump, it seems that the second stage may be your problem. Water in the receiver will only reduce the storage capacity and not give the symptom you describe.

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.

I set my mill so that the handles on the table are at a comfortable hight for opperation, I don't think I actually measured it when I built the bench it sits on.

Ian S C

Hi Clive,

Thanks for your reply,I never knew about unloaders. The only things I can see on my unit are the pressure switch,,which I use for starting it,and another connection which goes from the tank back to the pressure switch.This is fitted with a plastic disc which seals [I presume ] the connection.I can detect no leaks around it,nor is the drain valve leaking.I am beginning to think I may have internal problems [the compressor,not me ! ]

I have quite a different compressor - a Bambi. but have had two pressure switches fail with split diaphragms. I would double check for hissing from the switch unit.

Incidentally mine seem to be a standard pattern. The first replacement from Bambi cost over £60. The second from eBay less than £6.

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

Ah Robo !!!!! Happy days,alas, gone for ever !!

Anyway,my compressor still wont build up pressure. Heard no hissing from the switch either. Do I really need to take off the cylinder ? not looking forward to that at all,but if it,s the rings,so be it !

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

I've just had a look using a search engine to try to find some information on your " Ingorsol Rand 150" compressor.. It comes up with a lot of Ingorsol Rand compressors with 150 in the number. Can you give us some information about the compressor ? power rating (Or cu ft per minute and pressure.) Is it single or multi cylinder. Is it belt drive or direct drive ? If it is belt drive could the belt be slipping ?

Edit. I have just re read your first post and realise that you have eliminated a slipping belt.

Edit 2. If the rings were leaking I would expect to hear air coming out of the oil filling point on the crank case.

Les.

Edited By Les Jones 1 on 26/03/2017 18:01:21

Edited By Les Jones 1 on 26/03/2017 18:01:45

Edited By Les Jones 1 on 26/03/2017 18:19:52

Edited By Les Jones 1 on 26/03/2017 18:25:21

Edited By Les Jones 1 on 26/03/2017 18:26:08

Hi Les,

Just checked my compressor. I t is an Ingorsoll Rand Euro compressor with a 100 lt tank [dont know where I got 150 from ] It is driven by a 2hp single ph motor,belt drive. Dont hear any air leaking anywhere,so it sounds like it might be the valves. Can they be got on Ebay? the agent here charges mad money for parts.

This is a picture of my sick compressor. Found a few places on Ebay who supply Ingorsoll Rand spares,so I supplied all the details I had,model no,s ect only to be told that this was not an Ingorsoll Rand model. They seem to make about 500 different types,as far as I can see.

Back to the grindstone.

Edited By JasonB on 28/03/2017 12:30:18

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

Hi Larry,

unless they are craked they'll just need a clean........quite often, well at least the ones I've done were thin st/steel plates....prob 20 thou thick.... just clean everything with brake cleaner, knocking off the lumps with ur nail......I always give a thin coat of oil on the valves when refitting as u'll prob drop them.....there's usually no springs operating the valves on these small compressors, (BUT u never know) they rely on the spring in the metal.....often the valve is an elongated plate and when bolted down the head traps one end allowing the other end to move.....

when u lift the head the valves are in a steel or iron plate seperate from the head......sometimes sandwiched between the head and barrels or acutually in a recess in the head..can't tell from the photo.....the after cooler ( the thing between the head and the main air pipe) will prob need a gasket as well....looking at ur photo, loosen a couple of turns the main air pipe union under the cooler then remove the cooler from the head, then undo the head bolts......when u get in there u'll be surprised how much poo there will be...

REMEMBER to note which way around everything is.....take a photo, it's quite an easy job......try and save the head gasket if u can......My old comp which runs at 125psi only uses a conflake box as a gasket....... temparary/permenent u know......now have the proper gasket paper but never any time.....

good luck...Clogs

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.

The valves are reed valves, not valves in the conventional sense....

If you remove the screws and petals, dont forget to loctite the screw threads on reassembly....!! They can come lose....

The compressor I repaired not so long ago, needed at least one new reed petal- it had snapped just after the pivot point where it attaches to the block...(along with new con rod/piston/gudgeon pin and gaskets...)

Maintenance on these compressors is important, low oil levels can cause piston problems down the road, from partial seizure/broken rings to gudgeon pin/little end wear.....

Hopefully you will find what ails yours with a little dismantling...good luck.