Altaros Booster repair

So is it fixed?

I needed to change the HP piston seal on mine after only about half a dozen fills and top-offs of a 6.8 litre bottle. Mine had quite a bit of that black dusty crud inside as well. I think that it is graphite dust and it comes from wear in the large diaphragm drive piston body. It was probably the cause of my premature seal failure. I'd be interested to know what Altaros has to say about whether it's normal or not. I only keep mine as a backup now. I find my little YH much more convenient and the Altaros's long fill times burnt out my previous shop compressor. 

I needed to change the HP piston seal on mine after only about half a dozen fills and top-offs of a 6.8 litre bottle. Mine had quite a bit of that black dusty crud inside as well. I think that it is graphite dust and it comes from wear in the large diaphragm drive piston body. It was probably the cause of my premature seal failure. I'd be interested to know what Altaros has to say about whether it's normal or not. I only keep mine as a backup now. I find my little YH much more convenient and the Altaros's long fill times burnt out my previous shop compressor.

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Cant be!

The air is split on the inlet and work air goes directly into the main piston and is expelled as cooling air on the cylinders.

Compressed air is fed through the dryer and directly into the LP piston and from there into the HP piston via the white hose.

Maybe just maybe it's oil vapor that has accumulated over time?



Mine has done close to 300hours and the last stint was 6 x 6.8liter bottles from zero to 320bar in 5 days

Wow, I bet that cuts your fill times down. Do you really use that or are you just pulling my leg?

..Mine had quite a bit of that black dusty crud inside as well. I think that it is graphite dust and it comes from wear in the large diaphragm drive piston body...

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Yes it looked like greasy graphite dust but can't be from the drive piston, there is no connection to the high pressure side, the seal in the driving unit is an o-ring and I found it to be clean besides what I think was a thin layer of silicone oil

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I was referring to what you call the standing seal. It was the cause of mine not building pressure and assume that it was that seal causing your problems as well. In my case, there was a lot of black dust that appeared to be from wear from the central drive piston. It had made its way past the dust cap and retaining ring to the HP seal, hastening its wear. From what I remember the drive piston does not have any sealing rings or lubrication. My diagnosis may not have been correct and the seal and piston may not have been adequately lubricated from the original assembly. I have no idea why you have that gunk build-up in that valve area.

Mine is the older model in the plastic tackle box. It doesn't have the gauge on the HP side but is almost identical to the tin box types. I didn't need to remove the drive piston but I assumed by the way it felt that it was just a precision fit. There was definitely some rubbing going on by the wear marks on the inner cylinder surface and the black powder. The special lube that they sent me with a couple of new seals was clear and looked exactly like the Molykote 111 silicon grease compound that I use on all my O rings. At the time, they said that it was special stuff and would outlast whatever they had used in the past. I suppose that white stuff that they sent you is just the same poop with a different colour.

Mine has done close to 300hours and the last stint was 6 x 6.8liter bottles from zero to 320bar in 5 days

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Did you change that seal? - could be the picture but is looks like it has a low point like mine had - besides that it look squeaky clean, no black stuff

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You are right mate!

I just pulled it and looked and indeed it has a burned spot. Flipped it 180deg and it should be good for several hundred hours again.

I will pop a mail to Ondrej and order a couple just for safe keeping.

If you ever need to make another then might i propose Teflon?

It deforms slightly and will over time form a tighter seal than Delrin and it will definetly stand up to the heat!



Oh and i have stocked up on spares so if you need anything in a hurry shoot me a PM!

Yesterday while filling my bottle, during the fill the fill rate slowed down.

suspecting a air leak, I shut off my compresser cooling fans to see if I could hear or feel anything leaking.

On the high pressure piston, near the cooling exhaust port, I heard a new sound; not the usual Darth Vader breathing sound but between the cooling air exhaust pulses, I could hear what sounded like air moving inside the HP Piston assembly. There did not seem to be any air escaping, just the sound.

I have around 75 to 90 hours on the Altaros Booster at this time, it is still pumping, but does seem slower.

When new, HP piston used to squeak when when the fill pressure was over 4000 PSI, it was in the same location I am hearing the air moving. Altaros said I could add a couple drops of silicone oil in the line now and then, and it did stop the squeak. After that I usually just filled to 4000 psi.

Any ideas on what this could be?

Thanks for this very helpful thread and your answers.



Regards,

Roachcreek