I expect it is forthcoming as a third stage service needs the head to be removed. Remember the UK is 5 hours ahead of Eastern time and Iain has been working late to get us what he has so far. Much appreciated Iain hope you realize just how much.
Rix SA-6 Parts
- Thread starter rob.mwpropane
- Start date
Please register or login
Welcome to ScubaBoard, the world's largest scuba diving community. Registration is not required to read the forums, but we encourage you to join. Joining has its benefits and enables you to participate in the discussions.
Benefits of registering include
- Ability to post and comment on topics and discussions.
- A Free photo gallery to share your dive photos with the world.
- You can make this box go away
Service Inspection Report 5 is the compressor inspection prior to being accepted into the works for service. One thing to note (Iains dirty tricks) is the thrust rider comment is only for commercial or military customers.
For private individuals I would suggest simply turning that worn rider ring over and offering a fresh ground face to the bearing. In effect you get double the life. Although had it been greased with a just little grease more often like the label say's this would not have been an issue and the thrust rider would have been fine.
Now from a commercial or military perspective we don't do this swapping plate faces over as they need the spare fresh face option to invoke Iains dirty tricks part 2 and swap it then when you're back in that field with a just a spanner, cows and grass.
Enjoy Iain.
( if that is in all honesty possible watching some dude poking his fingers around pretending like he knows what he's doing) But at least the power is off LOL
https://youtu.be/Wh390_cyhhA
For private individuals I would suggest simply turning that worn rider ring over and offering a fresh ground face to the bearing. In effect you get double the life. Although had it been greased with a just little grease more often like the label say's this would not have been an issue and the thrust rider would have been fine.
Now from a commercial or military perspective we don't do this swapping plate faces over as they need the spare fresh face option to invoke Iains dirty tricks part 2 and swap it then when you're back in that field with a just a spanner, cows and grass.
Enjoy Iain.
( if that is in all honesty possible watching some dude poking his fingers around pretending like he knows what he's doing) But at least the power is off LOL
https://youtu.be/Wh390_cyhhA
Golan68
Registered
Golan68
Registered
lain, in the workshop manual it's said that detregent is bad for the teflon rings, why?
No it does not say that in any of the manuals, but you do bring up a very interesting question.
The short answer.
Is when your cleaning the compressor with a brush and a bucket of soapy water don't flood the piston liners with water and nothing to do with the choice of detergent.
The long answer.
There is another document for this pump called the Design Philosophy Review we did this for both the Royal Navy and the RAF before the UK SA-6 variants were accepted into service. In these documents they go into much more detail and more important a procedure review of how to operate, service, field service, breakdown maintenance etc both in the field (your dive site) and back in the depot or workshop (back home or at the LDS for reference)
Now please keep in mind that your dealing with engineers here, we know what we're doing just not so good in explaining.
But what your referring to in the US manual I posted was with regard to general cleaning of the external compressor parts, the understanding being using a small hand brush mild soap *detergent and water. From memory I think it was *Joy Soap (but NOT Simple Green)
By contrast our engineering review this side ranged up to and included using power jet washers or steam cleaners as per a standard mil procedure. Now on the one hand that would be fine however the risk assessment calls up what would happen if the water jet gets past the rings or with a steam cleaner the heat softening the fan shroud and belt guard in addition to if water gets behind the pistons and into the heads.
The question then was to define just how much water is allowable, a little not a problem a lot and the problem increases to the point of if you could induce hydraulic "Lock" when enough water gets inside and water being incompressible under pressure that it cannot get past the valves and reed lift spaces fast enough and in effect locks the compressor up when you restart it.
In our workshop design review it was concluded that the large tolerance between the piston and the piston liner on each stage was sufficient for the soft PTFE piston ring to safely extrude out (like a bust disc) and release any water at the front end (fan side) but as our risk assessment included nuclear biological chemical NBC considerations together with contaminated water hazards from the cleaning etc etc it gets complicated.
One of our extreme tests was to submerge the compressor block only underwater by hanging on its side by a hook then pull it out attach the power cable and start up with some small additional no tool hand adjustments such as opening the condensate drains and turning the compressor by hand before re starting.
Another test concocted for a Civil Defence project (our version of Homeland Security) was a low temperature -30C start test for NATO.
Now I interpreted this to keep the compressor with an electric motor in an industrial fridge at -30C for 24 hours then drag it outside and start it up. It passed fine.
However by contrast one of our competitors a much loved brand and used by many forum members using an oil lubricated compressor design preferred to interpret the testing requirements differently to ourselves by dragging their compressor out of a warm +21C workshop into a fridge at -30C to simulate starting at -30 C atmospheric ambient as meeting the required test conditions and they also started fine. They were cheaper and won the tender.
Now as these compressors together with the rest of the emergency kits sit in numerous unheated 20 foot containers around a non disclosed NATO EU country I trust that if and when they are needed in anger its in the summer.
Just to illustrate that the devil is sadly for some of us both in the deception and in the detail.
Iain, thanks for all the information and videos in this thread, they are really helpful. Are you saving the best for last which would be the video showing the removal and service of the heads and 3rd. stage piston. I know I am waiting with baited breath for you to post it as I am confident after seeing the previous videos I would then be comfortable stripping down and servicing my unit. More potential sales for the US division.
Golan68
Registered
OP
@Golan68 why would you want to get water on the teflon inside the cylinder? To me, the statement in the manual is simply saying not to soak the walls / rings. I can imagine it would gum the rings up pretty bad.
Actually, I read a post by @SurfLung where he put his Rix back together and it was't 100% dry (or something along those lines) and it gummed things up. He found a good buildup when he took things back apart and had to replace the rings (maybe he can chime in and confirm / clear up that part).
I "think" it would make more sense to remove pitons, remove the rings, clean the pistons / cylinders, then make sure everything is 100% dry and reassemble (or replace rings). I can't see any point to cleaning teflon rings / riders or viton o rings with any type of detergent, and especially not while they're together... but I'm not sure. Just my take.
@iain/hsm I'm with @grf88 .... waited with baited breath for the last few videos. I'm sure you've had a busy weekend. I've watched the 1st 4 numerous times and each time I pick up on something else. Very grateful for your efforts.
Actually, I read a post by @SurfLung where he put his Rix back together and it was't 100% dry (or something along those lines) and it gummed things up. He found a good buildup when he took things back apart and had to replace the rings (maybe he can chime in and confirm / clear up that part).
I "think" it would make more sense to remove pitons, remove the rings, clean the pistons / cylinders, then make sure everything is 100% dry and reassemble (or replace rings). I can't see any point to cleaning teflon rings / riders or viton o rings with any type of detergent, and especially not while they're together... but I'm not sure. Just my take.
@iain/hsm I'm with @grf88 .... waited with baited breath for the last few videos. I'm sure you've had a busy weekend. I've watched the 1st 4 numerous times and each time I pick up on something else. Very grateful for your efforts.
PrffsrE
Registered
Before I start. You should gently remind @iain/hsm to show you and explain the piston storage tube for the third stage. If it is anything like the one I had (for the 4VX's 4th stage) it is very important and helps a lot getting that floating piston and all those rings back in the bore hole!
I believe that Iain stated it pretty clearly when he said: "One of our extreme tests was to submerge the compressor block only underwater by hanging on its side by a hook then pull it out attach the power cable and start up with some small additional no tool hand adjustments such as opening the condensate drains and turning the compressor by hand before re starting."
There is a huge gulf between what you can do and what you should do. Also add in liability and the stupid factor e.g. Iain told me that I could take the compressor underwater. LOL
When I was a young welder I wanted to fill my smaller 25 Cu.Ft. Oxygen cylinders and the cost per fill was 3/4 of a 200 Cu.Ft. Cylinder. So I went to the local Hydraulic Hose manufacture and purchased a 6' (2 METER lol) 10,000 PSI hose for OIL. I purchased 2 CGA 540 nipple and nut and have trans-filled many O2 cylinders. This hose was neither made or meant for Oxygen service!!!
Back to the show!
On my 4v compressor, in the original data my compressor was designated a Nitrox compressor. So when I ordered parts from RIX they had 2 part numbers one was normal and the other was O2 cleaned. The second was quite a bit more expensive (and more time)! So I ordered the standard part and I cleaned it. I unfortunately did not know that Iain was probably here on the forum all along. I had NO advice other than RIX. I purchased chemicals from GMC, Global Manufacturing Company (Now GSM Global Scuba Mfg out of Texas). I used ultrasonic cleaning solution to thoroughly clean the part then use Oxy safe citrate tank cleaner #44050 to re-clean the parts but also the new: orings, rider rings, pressure breakers and the pressure rings. Never touched the cylinder liners (Usually. See follow up) thoroughly dried them of course and re-assembled in the cleanest way possible! I am by no way saying that this is the correct way to do it and I am sure we will hear Great things from Iain tomorrow about this. But, I had no problems with cleaning the PTFE parts with a citrate cleaning solution meant for tanks and valves.
Where was I going with this???? Oh yes.... Things you probably, maybe, outa, shouldn't do! (like taking your compressor diving! I just love that!)LOL
Touching the cylinder:
When I inherited the position and compressor, everyone had been using it like a home appliance and it had not been serviced in a LONG time. They did not even ask themselves: Why does it take all day to fill the banks now? I dug out all of the paperwork. Fortunately for me they saved it all. I contacted the last guy that the shop had work on it and when he showed up in a big diesel service truck with black grease on his hands clear up to his elbows I told him "you can't touch the pistons with grease on your hands" he said "Why not?" I told him I would do it myself! When I removed that 4th stage piston for the first time. The rings were gone. GONE! some of the orings to! Pressure breakers gone! I replaced them all and they wore out rather quickly. After many telephone conversations with (Rick Stolquist If memory serves and Christina Torncasa in purchasing) I was informed that running the free floating piston with insufficient rings will allow the piston to slop around in the cylinder and cause wash boarding of the cylinder walls. I was told to hold the cylinder up to a bright light (My cylinders were removable) that you could see the wash boarding. Yep. That is what happened. Then I was informed that a new cylinder was $2500, + shipping and I had to wait for one to be manufactured! I read the manual from cover to cover and it was one of those field service manuals Iain talks about. It stated that if you measure the bore and it was within tolerance that you could hone the cylinder! WOW field repair! Now I have honed automotive cylinders but this a precise instrument? (A good time to mention that the liners of the 4V are not removable) So I purchased a 1200 grit ball hone, it was not long enough. build extension. But what about the oil? You have to use LOTS of oil and what of the steel, stone and oil left behind? Well I called my longtime hotrod mechanic friend Bill McFeeters and he said: "I put mine in the dishwasher"! So this delicate instrument was field honed with lots of oil, dishwashered (Is that a word?) and reassembled after lots of O2 cleaning and it worked perfect till the day I replaced the whole compressor. (Very sad day)
By the way. RIX told me over the phone that I could not do it. It was not part of the specifications! I did it.
So to end. Like Iain said, Don't touch it or do it right!!!
Wow this went long! I can not wait to see the replies!
I believe that Iain stated it pretty clearly when he said: "One of our extreme tests was to submerge the compressor block only underwater by hanging on its side by a hook then pull it out attach the power cable and start up with some small additional no tool hand adjustments such as opening the condensate drains and turning the compressor by hand before re starting."
There is a huge gulf between what you can do and what you should do. Also add in liability and the stupid factor e.g. Iain told me that I could take the compressor underwater. LOL
When I was a young welder I wanted to fill my smaller 25 Cu.Ft. Oxygen cylinders and the cost per fill was 3/4 of a 200 Cu.Ft. Cylinder. So I went to the local Hydraulic Hose manufacture and purchased a 6' (2 METER lol) 10,000 PSI hose for OIL. I purchased 2 CGA 540 nipple and nut and have trans-filled many O2 cylinders. This hose was neither made or meant for Oxygen service!!!
Back to the show!
On my 4v compressor, in the original data my compressor was designated a Nitrox compressor. So when I ordered parts from RIX they had 2 part numbers one was normal and the other was O2 cleaned. The second was quite a bit more expensive (and more time)! So I ordered the standard part and I cleaned it. I unfortunately did not know that Iain was probably here on the forum all along. I had NO advice other than RIX. I purchased chemicals from GMC, Global Manufacturing Company (Now GSM Global Scuba Mfg out of Texas). I used ultrasonic cleaning solution to thoroughly clean the part then use Oxy safe citrate tank cleaner #44050 to re-clean the parts but also the new: orings, rider rings, pressure breakers and the pressure rings. Never touched the cylinder liners (Usually. See follow up) thoroughly dried them of course and re-assembled in the cleanest way possible! I am by no way saying that this is the correct way to do it and I am sure we will hear Great things from Iain tomorrow about this. But, I had no problems with cleaning the PTFE parts with a citrate cleaning solution meant for tanks and valves.
Where was I going with this???? Oh yes.... Things you probably, maybe, outa, shouldn't do! (like taking your compressor diving! I just love that!)LOL
Touching the cylinder:
When I inherited the position and compressor, everyone had been using it like a home appliance and it had not been serviced in a LONG time. They did not even ask themselves: Why does it take all day to fill the banks now? I dug out all of the paperwork. Fortunately for me they saved it all. I contacted the last guy that the shop had work on it and when he showed up in a big diesel service truck with black grease on his hands clear up to his elbows I told him "you can't touch the pistons with grease on your hands" he said "Why not?" I told him I would do it myself! When I removed that 4th stage piston for the first time. The rings were gone. GONE! some of the orings to! Pressure breakers gone! I replaced them all and they wore out rather quickly. After many telephone conversations with (Rick Stolquist If memory serves and Christina Torncasa in purchasing) I was informed that running the free floating piston with insufficient rings will allow the piston to slop around in the cylinder and cause wash boarding of the cylinder walls. I was told to hold the cylinder up to a bright light (My cylinders were removable) that you could see the wash boarding. Yep. That is what happened. Then I was informed that a new cylinder was $2500, + shipping and I had to wait for one to be manufactured! I read the manual from cover to cover and it was one of those field service manuals Iain talks about. It stated that if you measure the bore and it was within tolerance that you could hone the cylinder! WOW field repair! Now I have honed automotive cylinders but this a precise instrument? (A good time to mention that the liners of the 4V are not removable) So I purchased a 1200 grit ball hone, it was not long enough. build extension. But what about the oil? You have to use LOTS of oil and what of the steel, stone and oil left behind? Well I called my longtime hotrod mechanic friend Bill McFeeters and he said: "I put mine in the dishwasher"! So this delicate instrument was field honed with lots of oil, dishwashered (Is that a word?) and reassembled after lots of O2 cleaning and it worked perfect till the day I replaced the whole compressor. (Very sad day)
By the way. RIX told me over the phone that I could not do it. It was not part of the specifications! I did it.
So to end. Like Iain said, Don't touch it or do it right!!!
Wow this went long! I can not wait to see the replies!
Geo7
Contributor
Similar threads
