Inspiration Strip downs and rebuilds

For the new owners amongst you and for those who are not mechanically adept here are details (including pictures) for a complete, step-by-step rebuild of the unit that anyone should be able to tackle.

Tools Required

Allen Key set
Thin nose pliers
6" section of soft wood Broom handle!!!! or a proper hose tool
Cable ties (I know a good trick with them)
Multimeter, preferably digital with a high internal resistance
Small cross head screwdriver
Blunt toothpick

Official tool for Scrubber head removal
Official Tool for T piece removal
Medium Pressure gauge

Removing and Replacing the Wing/Harness/Plate/Lungs

Replacing the BC/Wing is easy as it changing the harness or lungs. Here I detail how to put them all back together afterwards. In this case with Dive Rite Rec Wings and a Portland Oceaneering II SS backplate and harness. Personally I would of thouaght it was obvious how this all goes together and maybe it should have been shown to you during your training. But judging by the huge number of folks who email me asking how to do it, it obviously isn't being covered or you guys are not adventurous to undo 2 bolts and see whats under there

To remove all, use and allen key and a pair of thin nosed pliers to remove the 2 backplate mounting screws. Use the nose of the pliers in the 2 holes in the front button nuts to stop them rotating and the allen key round the back to unscrew the 2 large bolts. One holding the manifold in and the other in the centre of the moulding that the scrubber rests on. Unthread the harness from the insides of the lungs and your done.

The two bolts are arrowed and put back in, ready to receive the wing. Now the fun starts. Place the wing back onto the 2 bolts making sure the wing is sitting as low as possible so as not to stress the other the shoulder hoses

Make sure the wing is layed flat and the hose is out of the way. I'm using Dive Rite Rec wings here and yes those are bungies of death on them. I use my drysuit for buoyancy not the BC so my wings spend the whole dive deflated and the bungies ensure they are stowed neatly out of the way. They are aso great for tucking hoses and objects up. Its your call which wing you use. People have had success with the following,

APD 22Kg Red Wing
Dive Rite Rec Wing (original and latest shapes, but not the intermediate shaped one)
Custom Divers TDB (NJeed to cable tie the top together or it pushes the hoses
OMS Bingie wing (Again need to secure the top together)

The only downside I have found to replacing my wing is I now don't have that great side D ring to mount stages on. Buying the bigger APD wing leaves D rings in place. Its up to you if you also swap the Auto Air over or get rid of it (I have an OC/DSV fitted)

Now we need to put the lungs in. I've found this easier if you lay the straight out on the floor like so

Note you can see mine are beginning to bleach where I take mine in the swimming pool fairly often to practice drills. As with the original wings the white labels contain a serial number for that component. Note them down if you haven't already done so

Next we stick on the harness of backplate (your choice). I Went for an SS backplate for several reasons a) I'm used to them, b) They are dry when you carry the unit after a dive and c) The harness can have far more and better D rings than the original.

Again its critical that the backplate if fitted is no higher than the original harness as this controls the position of the lungs. Stick the harness on the floor and position the SS plate on it and move it up and down until you can see which holes to use to keep the tops level. In the Portland case its the top holes

Place the unit on the bolts (Here you can see the excellent handle the Portland II provides). I actually widened (good old Dremmell) the two holes so that the original APD botton nuts would drop into the plate hole and not sit proud. Fit the 2 Mushroom Button nuts to the bolts. (this needs you to push from both side. I find the bottom one is easy so I put that on 1 turn (enough to keep it secure) and them push the top together.

Rethread the shoulder straps up through the lung retaining straps and secure the unit

Now you just need a way of securing the lungs down to the harness if your not using the original. That's easy to accomplish and I think my way is easier and not only pulls the lungs down but also together leaving more room for your arms and stages

BC Strip down and rebuild

Harness Strip down and rebuild

Lungs Strip down and rebuild

Scrubber Strip down and rebuild

Mouthpiece Strip down and rebuild

A well serviced mouthpiece is easier to open/close and less likely to leak than one left for months. I would recommend at least a yearly strip and rebuild, but would suggest that more often is beneficial. I was fortunate in that Dave Thompson showed me how to do this as part of my original training

Tools Required: Flat blade screwdriver, small Phillips screw driver, tooth pick or other blunt tool, fine marker pen.

Consumables: Kitchen roll or cloth, Silicon grease. Possibly Mouthpiece service kit.

The mouthpiece is fairly straight forward to strip and rebuild and requires no special skills. They key part is replacing the locking screws in exactly the correct place. Too tight and the mouthpiece is hard to turn, too loose and the mouthpiece rotates too easily. I will show you how I ensure its correct on re-assembly

Remove the two Phillips screws on the underside of the mouthpiece and store them safely

Unscrew the hoses taking care to retain the O rings (just visible). Also notice the black marks on my unit where the screws are.

Now the hoses are removed, notice the Black O rings either end of the outer barrel and also notice the flap valves (one way valves), one is black and one is blue. The Blue one is the Inhale side in keeping with all other blue fittings (its actually impossible to put the valves back in the wrong way)

Notice the blue valve has grooves in it and the black valve is higher, notice also the rubber flaps are reversed even though both valves are face down. Hence one way flow. Also notice the O rings on each valve. Put the valves and O rings somewhere safe after clearing them

Remove and store safely the large flat headed screw bolt at the front of the mouthpiece. This bolt holds the two parts of the mouthpiece together while still allowing rotation. It projects into a groove in the inner barrel

Then push out the inner barrel from the outer. Careful with the large O rings that seal the two barrels.

Here we see the two sealing O rings, the two barrels and the mouthpiece sealing O ring that is still sat in its milled groove. Clean the o rings and put them somewhere safe

Carefully prise out the mouthpiece O ring. I use a fingernail, but a toothpick or other thin blunt object may help. Make sure you don't damage the O ring, or more importantly the groove. Clean the groove out. Also clean all the barrels

Now the controversy. Officially as the loop can contain Oxygen you should use an oxygen compatible grease, but they are not as good a lubricant as silicon. I choose to use high quality silicone grease (NB its cheaper from electrical suppliers than from dive shops) allowing for the fact than the loop is at ambient pressure rather than high pressure. I haven't caught fire yet. Use silicon at your own risk.

Carefully clean and inspect all O rings. Replace any that show evidence of flattening, nicks or any potential faults.

Place a small blob of silicon on each O ring and massage it all over. You should be able to feel any imperfections in the ring. You want it to be moist and shiny but not gunged upped.

Here we see the inner barrel and can see the thin groove on the left that the locking bolt sits in and the indentation on the right that provides the slot for the exhaust water to exit as you purge and rotate the mouthpiece. These are on the underside of the inner barrel. Make sure you understand the relationship between the two barrels and their fittings

Replace the large mouthpiece O ring with plenty of silicon grease and make sure it is well seated. Also place silicon grease on the raised surface on the inner barrel to provide lubrication between the two barrels. I've tried it both ways, no lubricant and with lubricant. The lubbed version is smoother and easier to rotate. Don't use too much though

Do the same for the inside of the outer barrel. This will ensure an easy insertion and that they will rotate smoothly at all times

Gently re-insert the inner barrel in the outer barrel, making sure that the mouthpiece O ring is not displaced (twist as you insert). Also make sure that the exhaust indentation and purge slot are aligned as you see above

Making sure the two mouthpiece holes line up, insert the bolt screw to hold the two halves together

Grease and replace the two large sealing O rings. Make sure they are pushed down into the grooves at the end or they will not seal on the end caps

Now grease the two flap valve O rings and replace them on the two flap valves. Put the flap valves back onto the mouthpiece. Note the blue mouthpiece goes on the end with the ridge built in. As you can see above the blue flap valve has a matching groove in it. Make sure the two mate up.

Now for the fun part. use a marker pen to make small marks on the inner and outer barrels level with the two locking screw holes. NB they are not always in the same place either side. This is to allow you to replace the hose fitting and grub screws in exactly the same place each time

Screw on the hose until the lock screw hole lines up with your mark. If your really lucky you can see down the hole to check the alignment. Insert a grub screw to lock that hose. Note that by marking both barrels you can easily see if the outer barrel has rotated at all while screwing on the hose

Viola!, one finished mouthpiece. Now all you need to do is test the seals and flapper valves work. Breath and suck down the hoses to check the one way operation and try inhaling through a closed mouthpiece. Finally replace the hose back on the unit and undertake all normal positive and negative pressure tests

Last check to do, inspect your mouthpiece for any perishing or splits. Make sure the cable tie is secure.

How to undo and retighten the Hose clamps

Solenoid Strip down and rebuild

Old slightly corroded injector. Note the corrosion on the exposed surfaces suggesting air carried moisture. Interestingly to the best of my knowledge there has never been salt water in my head

Old solenoid and new. Make sure you wire the solenoid back the right way. It does work both ways