compressor not making pressure

[Rich.H]

Okay friends of Compressor section of the mig-welding forum....................
I have a 3hp air compressor (Chinese Wealth) that isn't making pressure and I've only just noticed that the muffler air intake is missing, for how long I don't know??
As like a lot of companies these days they use off the shelf generic parts, slap them together and put their name on the side of the air tank and away they go.
The setup is the simple reed valve setup so I wondered could it be simply down to sucking in dirt and with a build up on the reed valves etc... that is stopping it seal and generating pressure?
(it was pretty bogging considering it is above the cylinder head) Also looking closer at the 2nd photo of the "U" shape reed valve, it isn't sitting flat (maybe the main reason)
Any thoughts and Ideas greatly welcome
Cheers
Rich

 

[Seadog]

Warped reed valves would be my diagnosis. They should be flat against the valve plate.

 

[not done it yet]

it was pretty bogging considering it is above the cylinder head

I’m afraid I’m apparently not up to speed with such nomenclature. Can you explain the meaning of the term, please?

Non-pressure build up could be caused by a number of faults, that being one of them. Was it working (or is this a recent purchase)?

 

[BarrieJ]

I'd be inclined to think the problem might well lie with the reed valve.
I had a similar problem with a small compressor that I'd been given, the air intake filter was missing and judging by the build up of green paint on the valve, had been for some time. I cleaned the valve, reassembled the head and all was well.

 

[Rich.H]

Thanks for all your feedback, I've had this "second owner" compressor for many years now. I mentioned it wasn't building up pressure, but thinking about it now there was some positive pressure in the tank when I drained it, hence why I thinking it is the reed valve causing the issue, there's only one way to find out.....
3 further head-scratchers
1) Looking for a set of cylinder head gaskets?, 2) trying to find out how much oil it takes as there's no markings in the casing?, and 3 the torque setting for the cylinder tightening down bolts?
if anyone have any suggestions, please let me know

 

[Seadog]

1) Gasket material, hammer, and ball bearing/wad punch.
2) It may be that it's level with the filler hole lip.
3) Until they feel tight enough. That's the way that I did the head bolts on my old IR, and no leaks from it. Yet! You do need a decent gasket material of course. Something like this would be suitable - https://www.ebay.co.uk/itm/264095421643

 

[Rich.H]

1) Gasket material, hammer, and ball bearing/wad punch.
2) It may be that it's level with the filler hole lip.
3) Until they feel tight enough. That's the way that I did the head bolts on my old IR, and no leaks from it. Yet! You do need a decent gasket material of course. Something like this would be suitable - https://www.ebay.co.uk/itm/264095421643

God making your own gaskets, that take's be back to my apprenticeship days, lol, had the foresight when emptying the oil out of the motor to collect it in an empty oil container with the level markers on the side which gave me a good idea of the volume it holds. thanks for the heads up on the gasket paper, much appreciated.

 

[Farside]

I'd go with my own experience of head bolts on other engines with alloy heads and barrels- 10mm bolts tend to be around 30ft/lbs, for example.