Reg servicing

[shermarama]

I'm having a go at servicing my own regs, being an engineering type with a comprehensive instruction manual and not that much money. This is the first time I've done it, though, so I'm being as cautious as possible.

The regs are second-hand (cf. the money bit) and some of the parts seem quite corroded. They're DIN regs and I'm having trouble removing the DIN adapter itself - it should unscrew with a 6mm allen key down the middle but it seems quite firmly stuck. I've given it about 15 mins in an ultrasonic bath in clean water, and a bit of a while sitting in a bath of 5% citric acid, but I still can't get that bit free.

Now, given that I don't want to do anything stupid, what can I try next? More sonicating? Longer soaking in citric acid? Anything else?

[nickb]

.... it should unscrew with a 6mm allen key down the middle but it seems quite firmly stuck ....

What regs?

[Ferg3333]

a longer hex key or other method to increase the torque might work. Then just tap lightly on the end of your new super long hex key. Hold the reg in a vice or something suitable that will not damage it.

But be very careful as you may damage it, if its not suppose to come off.

[Juz]

Do you mean this bit?



If it is, I'd give another go in the ultrasonic (with citric), after that it may be a case of being a bit 'bolder' with with the allen keys.

Juz

[bubbleless]

Hit it with a hammer, well a mallet , rubber/nylon type of thing to shock it.

Make sure the allen keys fit well, then you can extend them using a pipe or a spanner to get better leaverage.

Try that, as ferg says if its supposed to come off

[Richard Mason]

I wouldn't be putting the reg directly in a vice, too much wrecking potential.

I have a cut down stub from an old HP hose (but I imafine that LP would do), about 100mm long; I screw this firmly into the HP port and then hold the stub in the vice, as tight as needed so I can get a grip to then work on any other bits & bobs like your DIN fitting, without fear of damaging chrome or even putting a dent in the 1st stage.

[shermarama]

It's a Scubapro Mk 20, and I'm pretty convinced that this bit should come off. Vance Harlow's reg servicing tome agrees with me . I've removed the filter retainer, spring and filter, and then there's the deep 6mm hex socket behind that, which should remove the DIN adaptor from the body of the reg.

I've already been extending my levers, using a driver handle on the 6mm allen key, albeit gingerly since it's not a very robust handle. I might have to work up the nerve to be more forceful about it.

I'm holding on to the body of the reg with a 7/16" UNF bolt rather than an old hose end but yes, also a cunning plan!

I think what I probably ought to have asked is, am I likely to be damaging anything else by giving it more of a citric acid dunk? Is there a trade-off between getting rid of corrosion and causing damage to uncorroded parts?

[fishy69]

Try putting the reg in the freezer for a while then chucking it into some boiling water. Try and undo it then. Repeat as necessary.

[TerryH]

I wouldn't be putting the reg directly in a vice, too much wrecking potential.

I have a cut down stub from an old HP hose (but I imafine that LP would do), about 100mm long; I screw this firmly into the HP port and then hold the stub in the vice, as tight as needed so I can get a grip to then work on any other bits & bobs like your DIN fitting, without fear of damaging chrome or even putting a dent in the 1st stage.

It's quite common (well i've seen it a lot) to use the small soda-syphon
expired CO2 cylinders for general servicing, but i'm afraid if its on there
tight, relying on this or the above to clamp is likely to damage it,
remember it is only brass.

The reccommended servicing method is to put the body in a vice with
special profiled jaw blocks, that grip around the whole body.

[Dave Lev]

If a thread is stuck, sometimes it helps to try tightening a fraction just to break it free.