fishfriendzzz 11 Report post Posted January 15, 2015 Hi. I'm not sure if this is in the right spot but guess DIY covers repairs so here goes... I have a couple air pumps needing replacement diaphrams. I've managed to find and fit some, no problems. Where I am coming unstuck though is on trying to tension the bolt at the top of the diaphram, which connects to the magnet arm. Does anyone know of a technique or any tricks, tips etc for doing it? Blowing bubbles in a bucket doesn't really help much and adding air stones and tweaking while trying not to get wet and/or zapped... gotta be a better way? Cheers. Share this post Link to post Share on other sites
mattyd 0 Report post Posted January 19, 2015 If it is moderately tight you shouldn't get a noticeable amount of air leaking past the little bolt. There should be a small washer on the inside of the diaphragm that the bolt goes through, and that should also hold back some air. Maybe just smear some Vaseline in that area to add a bit more of a air-tight seal. I've repaired my various pumps heaps of times and I've never thought to worry about how tight to make the screw/nut/bolt thing. Share this post Link to post Share on other sites
aquaholic99 706 Report post Posted January 19, 2015 If you are talking about small airpumps, I remove the magnet arm, use a pair of needle nose pliers to hold the outside nut and a screwdriver to hand tighten the inside screw. Then return the magnet arm. You can dab a little locktight to stop nut from getting loose but I have never bothered. Share this post Link to post Share on other sites
mattyd 0 Report post Posted January 19, 2015 I think he was worried about air getting past the miniature bolt through the hole at the top of the diaphragm... and was asking whether there was some way of ensuring that the tiny hole was airtight by 'torquing' the little bolt Share this post Link to post Share on other sites
aquaholic99 706 Report post Posted January 19, 2015 Yes, that's what I was referring to. I always replace flapper valves as well if I have to change diaphragm. Share this post Link to post Share on other sites
Waggles 4 Report post Posted January 19, 2015 Yes, that's what I was referring to. I always replace flapper valves as well if I have to change diaphragm. Yes, I have been able to purchase replacement diaphragms easily enough; but where can i get the tinz winzy little flaps that actually flap close to allow the air to travel down the air outlet?? These I have not seen. Share this post Link to post Share on other sites
aquaholic99 706 Report post Posted January 19, 2015 (edited) Ask your diaphragm supplier for "flapper valves". If yours are failing (can't pump much volume or depth) and you are desperate, you can flip the existing ones over (use other side ) until you find new replacements. If your old diaphragm doesn't have any holes, your flappers are failing. They are made from thin sheet silicon if you are handy with a scalpel blade. Use the old one for a template Edited January 19, 2015 by aquaholic99 Share this post Link to post Share on other sites
Waggles 4 Report post Posted January 19, 2015 Thanks - "flapper valves" who would have thought it?? Share this post Link to post Share on other sites
fishfriendzzz 11 Report post Posted January 23, 2015 A flapper valve? Well that's one i haven't heard of before, but them i wasn't in boy scouts! I shall have to investigate further as it seems to be where i'm having issues. In the mean time, i found something of an interim solution. I applied a liberal layer of something called Dust Grease anti-wear technology. It calls itself a non-toxic food grade grease. It is particular thick and globby. Probably wont last forever but seems to be giving a good seal for now. Thanks to you both, I will be sure to investigate flappiness some more! Share this post Link to post Share on other sites
Donny@ageofaquariums 856 Report post Posted January 23, 2015 If you post the brand and model, likely theres also a part number you can order. XD prob just got myself banned from DIY section............ Share this post Link to post Share on other sites
aquaholic99 706 Report post Posted January 23, 2015 Just to get back onto the DIY theme, if you can't repair the diaphragm (or get the electricity back on) then an air mattress and air valve will keep you going for a while. A queen sized one (150 X 200 X 40 cm) is over 1200 liters! It will slowly deflate under its own weight. Share this post Link to post Share on other sites
fishfriendzzz 11 Report post Posted January 23, 2015 "Ummm hello? I'd like to order a ummm... flapper..." and that how people end up in newspapers! lol good point tho Donny. I wonder how glad wrap would go as a DIY version... *ponders* Share this post Link to post Share on other sites
fishfriendzzz 11 Report post Posted January 23, 2015 How now thats rather a novel idea aquaholic! Certainly could have some interesting possibilites... *ponders more* Share this post Link to post Share on other sites
aquaholic99 706 Report post Posted January 23, 2015 Actual flapper valves are extremely simple to make if you have thin silicon sheet. Use the old one as a template and a scalpel. They are very cheap to buy though. Share this post Link to post Share on other sites
fishfriendzzz 11 Report post Posted January 23, 2015 I'm sure i would have something somewhere that qualify as a silicon sheet tho cant think what or where. No matter, you've inspired me to have a hunt for something suitable! Share this post Link to post Share on other sites
aquaholic99 706 Report post Posted January 23, 2015 A thin even smear of silicon glue will suffice if you have a tube half open. Let it dry out of course. Share this post Link to post Share on other sites