Inflator maintenance - my orings are in a bunch

[SoCalSwami]

I'm looking for help to with my power inflator refurb.

My problem is the tiny oring on the stem which gets blown out of its groove during testing and pinches between hex and the cartridge.




Photos of the dissembled cartridge and components...




After I cleaned the parts in vinegar I re-assembled and plugged the power inflator into my usual low pressure line and tested.

Once pressurized, the tiny stem oring is getting blown out of the groove and pinched.
I discovered the pinched oring problem by removing the cartridge after the inflator 'stuck' open.

Couple more shots of the oring out of position.



What am I doing wrong?!?

I have tried both Nitrile and Viton orings. Tried 006 and 005 oring sizes. Tried more grease, less grease. Ungh!



Because this was my first experience cleaning my inflator valve, needless to say I was shocked at out bad the inside of the cartridge looked. Just dreadful. This led me to performing a few searched on SB and DMX, the results for 'sticky inflator' or 'broken power inflator' search were EYE-Opening. The results were 10 to 1. 10 accident reports vs 1 how-to service the inflator, which got my attention very quickly.

Is it just me or is the power inflator the red-headed step child of the scuba equipment world? No one seems to talk much about it, yet this little piece of gear could potentially fire me up the water column like a Polaris missile.

I will never neglect you again my Lil' inflator buddy [patting inflator on the button].

 

[bkotheimer]

Funny, I just finished rebuilding mine yesterday and dealing with the cartridge valve spool (the "stem" that is giving you trouble) making an unusual "snapping" action when I release the button. Had to compare it to a few different models at the LDS and talk to a few different people before I was convinced that it is normal.

Anyway, to your point, yeah it gets a lot of crud in it and I'm really glad I re-did it. But those two o-rings on the spool (#006 in my case) were REALLY hard to get back into place.... there's no way mine are going to pop out of their groove the way yours did. Are you experiencing this even with the #005 o-rings? Could it be too much lubrication on the INSIDE of the o-ring??

 

[SoCalSwami]

... those two o-rings on the spool (#006 in my case) were REALLY hard to get back into place....

Perhaps that's a clue. While the my Nitrile 006 rings were tough to get on, it wasn't that hard. And the Viton ring was also easy.

... Are you experiencing this even with the #005 o-rings?

I only tried the Viton 005 ring last night. I have not tried the 005 Nitrile.
I Nitrile set I bought does not clearly state the durometer, so I don't know for sure if they are 90D.

Could it be too much lubrication on the INSIDE of the o-ring??

I tested it both with LOTS of grease, and also wiped it all off so there was as little as possible. There was a high chance of the problem when I used more grease.

 

[redacted]

When you have an extrusion problem, you probably need to be using a harder (higher duro) o-ring. You also need to make sure that black replacement o-ring is the same size as the brown o-ring you removed. In the mean time, I'd stick one of the old o-rings back in the problem location and see what happens.

Folks don't spend enough time and effort cleaning, rinsing, and soaking those inflators. A tool to run FW through it is available and very effective.

 

[SoCalSwami]

Good news, it works. I've tested it this morning and there is no oring extrusion problem. It functions perfectly.

Bad news, why is it working??

Could the 005 viton oring have shrunken back to original size after being in the cartridge stem over night? I had to stretch it pretty good during installation.



Thanks awap, I've seen Tobin's inflator washer adapter, but never thought it was that important; I'm rethinking that opinion.

 

[SoCalSwami]

Per some advice, I checked the spool (what I previously called the stem) and it's bent ever so slightly.

While the inflator 'seems' to be working properly now, I will be replacing the cartridge as to avoid any chance to failure.

Thanks Bkotheimer and awap for the advice. I liked awap's idea to replace with old parts and and see what happens. I'll remember that one next time.

+1 on "Folks don't spend enough time and effort cleaning, rinsing, and soaking those inflators."
Amen Brother!

 

[bkotheimer]

Then you are about to embark on the journey I took earlier this week when I thought my spool was bent....

First, I went to Tobin at DSS, who could not sell me the "guts" for my inflator. He could only sell me the whole assembly for $46. That's everything that attaches to the end of the corrugated hose.

I also could not find any kind of rebuild kit at either of my local dive shops. And the one at DiveGearExpress was the tool and o-rings only.

Finally, I found one at Northeast Scuba Supply for $18.99:

I'd say this is very likely to screw right into your inflator no problem.

Of course, your LDS or online site would be happy to sell you the whole inflator for thirty or forty bucks, but, assuming it fits, the one at Northeast Scuba Supply seems like it will work for you.

 

[HenrikBP]

I've seen Tobin's inflator washer adapter, but never thought it was that important; I'm rethinking that opinion.

I bought both the inflator tool and the inflator flusher from Tobin. But if you don't have the "flusher" a good trick is to fill your BC/Wing with fresh water - inflate to pressurize a bit, and then flush the water back out through the inflator. Make sure you alternate between both the inflator button as well as the "oral inflate" button to rinse the entire assembly.

I rinse the dump valve the same way: fill - inflate - flush

When I'm traveling I do that a couple of times after each dive day.

Henrik

 

[cool_hardware52]

I also could not find any kind of rebuild kit at either of my local dive shops. And the one at DiveGearExpress was the tool and o-rings only.

What do you expect in a "rebuild" kit beyond the normal service parts, aka the orings?

Finally, I found one at Northeast Scuba Supply for $18.99:

I'd say this is very likely to screw right into your inflator no problem.

If John has cartridge valves for $19 buy some. That's a very fair price for a very hard to source item.

Tobin

 

[SoCalSwami]

What do you expect in a "rebuild" kit beyond the normal service parts, aka the orings?

If John has cartridge valves for $19 buy some. That's a very fair price for a very hard to source item.

Tobin

I don't want to speak for bkotheimer, but I imagine he is referring to a complete cartridge unit (both orings and metal) when he refers to a 'rebuild' kit. This was my first thought when I read it.


Someone posted a link to the Trident catalog which also sells the cartridge unit, but I'm not sure about cost. I might check with my LDS to see about custom ordering the parts.

In the meantime, Northeastsupply will be getting my order for several cartriges and some DSS tools.