Aluminum DIN dust cap is stuck...

[tfsails]

A couple of suggestions on how to get the aluminium cap off:

1. Take the reg to your LDS, pray he has a heated ultrasonic cleaner, and have him stick the whole first stage in there. This could loosen the corrosion enough to break the cap loose. It will also probably mandate a first stage rebuild in case any of the cleaning solution gets inside the reg.

2. Take your dremel tool and cut a lengthwise groove VERY CAREFULLY down the threaded part of the cap. I say "very carefully" because you do not want the cut to go down into the threads of the delrin wheel. When you're close to cutting through the aluminium, take a common screwdriver, stick in in the groove you just made and give it a good twist. If you've done it right, the aluminum cover will pop open and you'll probably be able to remove it by hand. If you still can't pry the cap loose, cut another groove somewhere else on the cap.

This solution could pose a problem if the cap extends way down the reg's threads and the cutting tool can't get down to the end of it because the DIN wheel is in the way.

 

[PriusDrIVER]

Alright, so I made some progress. What ended up happening was the entire DIN fitting unscrewed from the regulator housing itself. I happened to have a spare DIN conversion for my spare Mk2, so I just robbed the spare for the time being.

It seems the aluminum cap is pretty welded on there. I had it soaking in a vinegar water bath for hours, going back to try again. I also tried applying a bit of heat, that made no difference...what ended up happening was the entire thing just unscrewed.

So, worst case I am out the DIN conversion. I guess I'll just order another one and mark it up as lesson learned, who has the best deal on these anymore? LP has them for $50.

 

[PriusDrIVER]

Oh, the best part is that this is the Mk2+ I bought at retail from the LDS. The other 3 I have were on the bargain closeouts from scubatoys...I just find it funny that the one I had problems with is the one that came from the LDS (though the DIN kit was bought elsewhere, they installed it).

I've already learned one of the advantages of the DIN, no special tools needed to put it back together. Just some hex keys, unlike that ridiculous socket needed to get the yoke on/off.

 

[cwkline]

Prius,
Now that the whole thing is off, can't you put an allen wrench in the adapter and use a wrench or vise on the cap? You may have to ruin the filter if it won't pop out, but that is cheaper than the conversion.

 

[marchand]

Have you tried penetrating oil or solvent? Liquid wrench or PB blaster should work wonders.

 

[DA Aquamaster]

In a perfect world if you screwed it out of the reg you would be able to get a 6mm allen wrench in the reg side of the fitting. But it is not a perfect world as the diameter of the hole below the hex portion of the retainer is smaller than the diameter of the allen wrench you need to use. Which means you now have no eal way to put any significant torque on the DIN retainer.

But you do have a couple options. Clamp the DIN cap in a vice and then tap the end of the cap with a hammer several times to loosen the crusty stuff inside. Let it soak in 50% vinegar and water over night, then screw it back in the reg fairly tight and then tap the end of the DIN cap again and try to remove it - you can apply as much torque as the 20ish ft pounds you should use to put the retainer back in the reg. If that does not work, take it out, soak it and repeat.

If you use the dremel tool approach, be careful not to cut all the way through the aluminum - you do not want to cut into the threads of the DIN fitting. Cutting a pair of grooves 180 degrees apart will let the DIN cap spread slightly when you try to remove it, so it may help if soaking alone does not do it.

If you screw it up, I do have an extra (lightly used) DIN wheel I can sell you. I have the wheel and the retainer but SP does not sell the little part in the middle that holds the o-ring, so I cannot put together a whole DIN conversion kit.

Alterantively, I'll buy your DIN conversion kit for $10, cut the end off the DIN cap and remove the little center piece to put with my parts.

 

[Jeff Toorish]

Try some vinegar on the threads. Don't soak the whole thing, set the regulator so the threads and cap are down. Then either suspend or balance the reg in a dish of 50% white vinegar that just covers where the threads are exposed. If that doesn't work, channel locks are my next best idea.
Good Luck
Charlie
PS: I had the same problem, changed my caps to delrin.

White vinegar.

 

[halocline]

I would try Awap's suggestion of heat, cold, heat, cold, and don't be afraid to get the thing VERY warm, like too hot to touch for more than a few seconds. It'll come off. If this is the older style SP DiN connector you could drill a hole in the end of the cap to get access to the 6mm hex fitting, put a long allen wrench in there, clamp the cap in a vice, and turn clockwise. If it's the newer style that has the smaller allen fitting to hold the filter in place, you're out of luck on that idea.

 

[Hallmac]

Lysol Toilet bowl cleaner and water works wonders as well. I use a 50/50 mix and a 20 minute soak followed by a hot water rinse.

 

[Slonda828]

Just put it in an ulstrasonic cleaner. If your LDS boned you by giving you a crappy cap, have them put it in their ultrasonic for like 20 minutes, with heat, and it'll break loose. I've gotten corrosion a quarter of an inch thick off of old double hose regulators with a good ultrasonic. Then take that crappy aluminum cap, throw it at the mouth-breather who sold it to you, and find a spot in the corner of the shop to surreptitiously urinate in.