Tore My Rix SA-6B Apart
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number 4.... that there was funny. Thankfully I have a spill cover on my keyboard from the coffee, but boy did it hurt coming out of my nose....
Golan68
Registered
my understanding is as follows :
1. the real expert is Lain !
2. there is a difference between dynamic sealing and static sealing.
3. we have one trapped pressure between the fill hose valve and the third stage head valve.
4. we have another one between the first dryer [2nd state] and the third stage piston.
so, if you lose air on the high pressure side it the one way valve at the head that is leaking.
if you lose pressure between second and third it can be third stage piston static leak or maybe second stage valve that lets the air return.
now, unless the compressor is struggling to build pressure why would you care? Lain might correct me , but I don't see a reason to be worried if the third stage is hissing when the compressor is stopped.
and last, the valve should be clean, with the Rix it's so easy so start there.
If I want be lazy I will post some pictures of the deep rabbit hole I went into ...
Golan68
Registered
OP
I am losing air back to the 2nd stage, so something isn't right. I'm assuming that the dirty head is causing a lot more air to be able to come through the 3rd stage piston vs what is normal. As in I usually turn it off and maybe I get a slight hiss as air comes through from the cylinder (but never really noticed), but now I'm getting much more air from either after or before the head and it's much more noticable.
Live and learn I suppose.
Also, a contact over at Masterline said that blow by from a new 3rd stage / clean cylinder is expected to be more in the beginning as the the teflon wears and coats the liner.
@iain/hsm I may not have the greatest tools or all the knowledge but I am trying here, lol. Appreciate your picture, I did get a good laugh. Iain is part 4 missing on YouTube or you just never got around to it? I don't think I would need your # if I had that!!!!
On a more serious note regarding the SA-6 liner a couple of pointers to look for.
1. Check for what is called washboarding.
Look it up, its a ripple effect created in the liner during use.
When machined the liners are heat treated ground and honed its an old mil spec process.
Can't say if it would be better to make it cheaper with a greater clearance slip fit and replace more often 10 years say or keep with the hardened stainless and suffer the eye watering cost on replacement and having to sweat it out with a taper punch die on a Enerpac hydraulic pusher. And that's another tool system for your tool box.
2. Check for Internal wear.
As with the 2nd and 1st stage liners they are replaceable but with the 1st & 2nd you can feel the wear with your finger at the TDC area around the liner where the piston never reaches and if you can feel a ridge around the liner at the head end. Excess wear will cause blow by. Rob you need another tool for the tool kit to measure called a 3 point micrometer.
3. Corrosion internal in the bore.
Rob you stated that you cleaned the liner using soap and water, Its the water that's the problem. The SA liner is an austenitic precipitation hardened stainless it will corroded but its hard and its the trade off between life expectancy and cost again. Also can I suggest you oven dry these types of parts 20 minutes at say 150C Use gloves after and don't tell the wife or share the oven with the thanksgiving turkey.
1. Check for what is called washboarding.
Look it up, its a ripple effect created in the liner during use.
When machined the liners are heat treated ground and honed its an old mil spec process.
Can't say if it would be better to make it cheaper with a greater clearance slip fit and replace more often 10 years say or keep with the hardened stainless and suffer the eye watering cost on replacement and having to sweat it out with a taper punch die on a Enerpac hydraulic pusher. And that's another tool system for your tool box.
2. Check for Internal wear.
As with the 2nd and 1st stage liners they are replaceable but with the 1st & 2nd you can feel the wear with your finger at the TDC area around the liner where the piston never reaches and if you can feel a ridge around the liner at the head end. Excess wear will cause blow by. Rob you need another tool for the tool kit to measure called a 3 point micrometer.
3. Corrosion internal in the bore.
Rob you stated that you cleaned the liner using soap and water, Its the water that's the problem. The SA liner is an austenitic precipitation hardened stainless it will corroded but its hard and its the trade off between life expectancy and cost again. Also can I suggest you oven dry these types of parts 20 minutes at say 150C Use gloves after and don't tell the wife or share the oven with the thanksgiving turkey.
Golan68
Registered
OP
I have read it front to back, but my hand aren't in it every day like you and I surely don't have anywhere near the experience.
No ridges on any liner, they all look in really good shape.
@Golan68 I did use a dremel and a stainless steel wire brush at the end because Iain said the piston never reached that far (and that's what he suggested) . I never went past the corrosion, so maybe 1/4" into the cylinder. It looks better, but still not perfect.
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