Compressor problems.

[Guest]

I have an AS186 compressor, the generic tanked one that lots of people re-brand. Got it from ebay about 6 months ago.

Last couple of days it's developed a fault whereby it will start and run fine, but once it's hit pressure and shut off, it won't always start back up. At first I thought pressure switch but the motor is actually humming so it must be getting the signal to fire up, it just won't spin over.

I've had this on other compressors when they've got too hot and expansion has seized the pump a bit so the motor hasn't got the power to get it initially going, but I'm not sure that's the problem here as sometimes it has only run for a few minutes, with a large desk fan pointed at it, so is still pretty cool. If I leave it switched off long enough it will fire back up when powered on though, so it has me baffled.

Has anyone had or heard of a similar issue, or can maybe shed some light on it for me?

Cheers,
Andy

[Steve Jones]

When I had this problem I turned down the pressure a bit. However I am sure you have tried that. When I had another pressure issue it was due to dust and grit under the valve cover in the compressor. There is a good video on Youtube that shows you how to clean it out. When I first started modelling I brought a cheap compressor like this and it lasted three years which I thought was a fair return for £50

[stillp]

I'm sure you've drained the condensation out of the tank? (granny, eggs, sucking...)
Pete

[Guest]

Thanks for replying chaps.

Pete, yes, but thanks for the suggestion. I usually leave drain taps open on any compressor/tank when not in use out of habit.

Steve, will have a look into that. I wasn't expecting it to last forever but 6 months is a bit poor.

I've done a bit of spraying today and found that whilst it won't cut back in at the lower pressure limit like it should, if I empty the tank completely, either by the safety blow off valve or either of my water traps, it will kick back in. Will have a further hunt around before I get the spanners out! :smiling5:

[JR]

Very annoying Andy.
I have the same compressor, this morning the valve controlling the pressure went haywire, just kept increasing, no matter what I did .
Eventually I drained the air, switched off, and on and it's reset it's self.
The pressure control now works perfectly.
I've had mind since Sep 2015.

[Guest]

I'll give that a try too John, thanks.

[Jim R]

Hi Andy
This video is useful HERE The section where he takes off the head, cleans out the muck and makes certain the valve is seated correctly is in the middle of the video. Dead straightforward to do. I took the head of mine with no problem. It may not help but perhaps worth a look.
Jim

[Guest]

Cheers Jim, I'll take a look later.

[Dave Ward]

Andy, sorry to hear about the problem, I bought my AS-186 in September 2013 - and I haven't ever given it a thought - I turn it on, it works, and I turn it off. Mine has always been used indoors, next to my bench, so It never gets too cold, and the air it draws in is at normal room temperature - I don't smoke, and I don't have any pets, so hopefully the air is pretty clean!
Dave

[Guest]

That's a good innings!

Too busy building things to have a look at it today lol, so I'll probably take it to work with me over the weekend. A colleague and I built a compressor once from a selection of ebay scraps so I'm sure between us we'll figure this one out.

[Guest]

Fixed!

I'll add some pictures when I get home this evening but as suggested it was full of little bits of debris that look like they came from the piston ring/seal. I gave it a good clean and blow out and it's back to working as it should, cutting out at around 60psi then kicking back in once pressure has dropped to 40 odd.

Thanks for the help chaps.

[Steve Jones]

Nice one Andy. Saved yourself a few bob.

[Guest]

Yes Steve, I was a happy bunny.

Sorted the pictures out in case anyone's interested

Top of the piston with the bent reed valve and plenty of yellowish crud at the top of the bore

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The sandwich plate that fits over the piston

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Inside the top of the head showing some signs of corrosion and proper rough casting.

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A shot from further back showing how simple the design is.

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And a gratuitous toolbox shot.

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[Jim R]

Hi Andy
When I took mine apart it was the same - not as bad though. I turned the reed valve over so it sealed properly. Glad it has sorted out the problem.
Jim

[stillp]

If you can afford Snap-On toolboxes you could've just bought a new compressor! :tongue-out:
Glad you got it sorted though.
Pete