Took a gamble on a spares/repair compressor - symptoms suggested a faulty regulator/switch. Unfortunately after a bit of fettling, it struggles to go far above 60psi. Doesn't sound very bad, but just won't pressurise properly.

Whipped the head off (first time I've ever taken a compressor apart) and one of the reed valves (?) tha'ts shaped like an elongated D has a bit missing from it (approx 3mm in diameter chip) at the end where the ports are. So we've discovered the problem I think..


.. problem is it's a Nu-tools Nu-Air NA850 compressor, which I can't find any bloody record off! What are the chances of me finding one of these valve thingies? Alternatively.. is there anyway I can make one? It looks like it's just some sort of flexible 0.5mm(ish) steel, with two small 2mm holes for the locating dowels, and not much else complicated..


Cheers,
Pavs

nu tool is sometimes re branded nilfisk stuff, you might be able to make one from some shim steel if you can get some the right thickness

hth

Ray

Hi Pav.
Some of the older industrial refrigeration compressors use the same type of valve, check local scappy as they get weighed in. If no luck let me know of size and will check at work as we did have some scrap units.

get a bit of shim, and get one laser /water cut

last time my compressor broke just like yours i used a feeler gauge to fix it
adam

Is there no way of fitting a non-return valve external to the head?

Thanks for the responses everyone! I don't have a micrometer to measure the thickness of the shim, but here's a photo on mm scale paper of it in case anybody recognises where I can get a replacement.

http://picasaweb.google.com/lh/photo/dVj938L-JzIkGdaY9DPZGQ?feat=directlink


Adam - that's a brilliant idea - what did you use to shape it? Did you just cut it with shears/chunky scissors? did you need to flatten it after?



After I fix it I'll have to take apart hte rest of the compressor casing to try and find the broken bit (don't want it causing damage, although in all likelyhood as it's on the exhaust port it's probably in the tank..)



Finally, is it okay to use cereal box cardboard to make gaskets for the compressor in case I tear one? I know it works well for inlet manifolds on old minis just not sure how well it would do for a compressor!

Cheers everyone

Pavs

yep cereal box is fine. If you're not sure wipe it over with silicone to make a very high tech "composite" gasket!

How about using an inlet membrane from a two stroke bike? A bit like this: http://www.honda-m-shop.nl/nl/105-membranen/894-membraanplaatset-malossi-3-diktes

It seems every compressor has a different design/shape of these valves (the last link included).

Feeler gauges seem like a brilliant idea but this valve is 19mm at it's widest point and all my feeler gauges are narrower than this.

Anybody have any shim steel or un-needed feeler gauges (approx 20mm by 50mm blank) that they could post to me for a quid? Obviously if anybody can actually cut me this valve (I can do a CAD sketchup), I'd be happy to pay a modest amount for it!

I'll measure the thickness at work tomorrow as I don't have a micrometer.


Incidentally, when cutting it out, do you just use snips?

Cheers everyone