Overhaul - Aqua Lung Titan 1st - diaphragm is stuck like glue

[beachnik]

Has anyone had any actual experience & success solving a similar problem?

- - - -

First of all, I’ve rebuilt these things before, without problem.

Not that it would matter, but I’m disassembling the ’T’ shaped Aqua Lung Titan 1st – the model introduced in 2010.

I don’t use compressed air to blow out the diaphragm, and even if I tried, this thing would not budge - it is stuck like glue.

The technique I normally use is one described by Aqua Lung as the 'alternate diaphragm removal method':
-I remove the standard pin that goes thru the orifice and into the Pin Support.
-Next I insert a pin tool thru the orifice and then into the pin support.
-I press on the pin support, the diaphragm flexes - and ‘normally’ - the diaphragm pops off, but not today. It's flexing plenty, just stuck at the shoulder where is forms an air tight seal with the body.

I’ve also tried:
-soaking in water to see if the diaphragm would loosen up.
-soaking in a mixture of water and white vinegar (over night)
-put it in my ultrasonic cleaner (water and a little vinegar)
-used my painter’s Heat Gun to warm up the body and diaphragm
-Gunk Penetrating Oil
...none of this worked.

Things I haven’t tried:
-Use an Xacto knife to put a slice into the diaphragm adjacent to the ‘pin support’ - then needle nose pliers to grab/pull the diaphragm out. It’ll require a lot of force and I can just see me accidentally wacking the internal threads on the valve body, which is why I haven't tried it.

Has anyone had any actual experience & success solving a similar problem?

 

[James79]

On conshelfs of indeterminate age I've used a double hook pick to puncture the diaphragm just inboard of the sealing surface and pulled the diaphragm out that way. Some have been so stuck that once I got a part of the edge up I reverted to pliers, similar to your plan.
Good luck, they can stick something fierce !

 

[Fibonacci]

I've overhauled a few Aqualung first stages that were very poorly maintained... and while the diaphragms were pretty crusty around the edges where corrosion had grown blowing it out with a compressed air nozzle through one of the LP ports worked every time.
I wouldn't cut it open either... yes, too great a chance of scoring one of the surfaces underneath.
If you have removed all plastic and other rubber parts so that only metal remains, try soaking in some acetone, that will dissolve all sorts of hardened gummy deposits. Rather than dunk the whole first stage in acetone, you could try pouring some ~20mm deep in a small ceramic or metal dish and stand the diaphragm end of the reg in it for 15mins or so.

 

[2airishuman]

Has anyone had any actual experience & success solving a similar problem?
[....]

Has anyone had any actual experience & success solving a similar problem?

Yeah.

Heat. Gentle heat.

 

[herman]

I have removed a number of badly stuck ones from old Conshelfs and DH regs. I cut a small X in the diaphragm near the center with an Xacto knife or razor blade ( no more than 1/2 inch across the X, the spring pad impression is a good guide to the limits of the cut) , pry up the edge (point) of the X and pull it out with pliers. Be as careful as you can when cutting it but the only thing under it is the pin support and if you scratch it some, it's not a big deal, simply sand paper off any rough edges. What you don't want to do is to try and pry it out at the edge. That is a sure way to mess up threads or the sealing surface underneath.

 

[beachnik]

Thanks to all of you for sharing your experience - much appreciated.

Herman, I did what you suggested - it worked well. In a day, everything will be back together and ready for a trip to Cozumel.

: )

 

[herman]

It should be obvious but I should have added to carefully inspect the sealing area around the diaphragm, often times stuck ones will leave parts of the old diaphragm which will cause sealing issues. Those have to be CAREFULLY removed with a soft item like plastic or wood dowel (chopsticks are great). Denatured alcohol will remove stubborn stuck rubber, esp if you let it soak overnight.