Help with ZD-987 desoldering station suction issue - Page 1
Forum section: electronics / repair

author: Mamejay
author_rank: Contributor
timestamp: April 26, 2015, 11:17:52 pm
content: Hello everyone,I am hoping that someone can help me. I have a ZD-987 desoldering station and have been using it for about the last 2 years.It has worked not too bad but lately I noticed the suction was terrible. The motor still sounds like its working fine.I opened the unit and checked the suction from there just using my finger on the input hose. I am getting basically no suction at all. The air output nozzle is blowing heaps of air so the pump is doing something.I have contacted the supplier but I doubt they will be able to do anything.My question is can the pump motor be replaced and if so where would I get one from? Also could it be an option to open the motor and see if an internal hose has come off?I have not opened it yet as I was waiting on the supplier to get back to me but I thought someone here may have had experience with a similar issue.Thanks

author: BradC
author_rank: Super Contributor
timestamp: April 27, 2015, 01:03:33 am
content: Quote from: Mamejay on April 26, 2015, 11:17:52 pmI would have done at least that before posting to the forum. Get in there and have a go!

author: Mamejay
author_rank: Contributor
timestamp: April 27, 2015, 01:21:51 am
content: Quote from: BradC on April 27, 2015, 01:03:33 amThanks for that Brad. Yeah I gathered as much but was just waiting on the supplier to see if he could help. Didn't want it look like I had played around wit it in case I had to send it back.I have been researching pump and found a bunch of 12v ones that are fairly cheap but have no idea if these would work.I will open it up tonight and see what I can see. I am hoping it is something simple.

author: Alex Eisenhut
author_rank: Super Contributor
timestamp: April 27, 2015, 04:34:43 am
content: I'm hoping it's not the valve plate inside the pump, if it's that kind of pump. If it is, I may be of help.

author: Mamejay
author_rank: Contributor
timestamp: April 27, 2015, 06:49:40 am
content: Excellent. I will hit you up once I know what is going on

author: Rasz
author_rank: Super Contributor
timestamp: April 27, 2015, 07:39:04 am
content: Quote from: Mamejay on April 27, 2015, 01:21:51 amyou have 2 year warranty on the thing? no? then why do you think opening will matter?if you want someone to fix it for you look for the nearest hackerspace, offer $50 and someone will do itif its blowing air out pump must be working, cheap aquarium type pumps dont produce enough vacuum to be effective, fixing pump can be easy, membrane is just a piece of rubberhere is teardownhttps://www.eevblog.com/forum/reviews/zd985-and-zd987-review-and-teardown/

author: Mamejay
author_rank: Contributor
timestamp: April 27, 2015, 12:26:27 pm
content: OK. We have a winner. Looks like one of the membranes has a crack in it.So now I need to find a replacement. Do any of you guys know where I can grab replacements?Might change both of them and also seal them up with silicon.Let me know what you guys think.

author: BradC
author_rank: Super Contributor
timestamp: April 27, 2015, 12:34:58 pm
content: I'm torn. I don't think silicone will stick to the rubber well enough to cope with the stress. I'm tempted to recommend cyanoacrylate (superglue) because that is what is used to join rubber O-Rings, but I don't know if it will stiffen things up and just cause more damage. A replacement would be the best thing, but where would you find them? I wonder if you could cast some new ones from platinum cured silicone?This stuff is 10 kinds of awesome for making replacement parts or making moulds to make replacement partshttp://www.barnes.com.au/addition-curing-silicone/pinkysil-1591. I used it recently teamed with some castable rubber to make some ortho-wiper blades for a HP DesignJet.

author: ozwolf
author_rank: Regular Contributor
timestamp: April 27, 2015, 12:44:37 pm
content: Quote from: Mamejay on April 27, 2015, 12:26:27 pmFirst, I'd try the supplier, failing that, that diaphragm does look like some of the replacements for aquarium pumps likehttp://www.theaquariumshop.com.au/shopexd.asp?id=2361&name=Hailea ACO 5503/5504 Diaphragm.I really wouldn't try patching it with silicon, it's never worked for me.Ozwolf

author: McBryce
author_rank: Super Contributor
timestamp: April 27, 2015, 12:46:09 pm
content: The glue that you get with cheap bicycle tyre repair kits is quite good at repairing these types of membranes. It's made for rubber, it's made to be flexible and it's made to seal. I fixed an aquarium pump with it last year and it's still holding up. Use lots of it and remove the excess that comes out the sides before it has set. Give it a good 12 hours drying time before you test it.McBryce.

author: Mamejay
author_rank: Contributor
timestamp: April 27, 2015, 12:53:52 pm
content: Quote from: McBryce on April 27, 2015, 12:46:09 pmPerfect! I will give it a try. To be sure I would prefer a replacement. Any ideas? There must be somewhere which can provide one.I found this one on eBay. Wondering if this would do the trick.eBay auction: #161361534113

author: SeanB
author_rank: Super Contributor
timestamp: April 27, 2015, 12:56:36 pm
content: Loctite has a black rubber filled superglue which will work here, it is flexible when cured. Otherwise Pratley Wondafix is a flexible polyurethane which is often used to do shoe repair and to fix rubber articles.If you want to have one made go to a seal maufacturer. Will cost a little but they will machine one out of silicone or EPDM rubber for you to the same specs as the old one.

author: Mamejay
author_rank: Contributor
timestamp: April 27, 2015, 01:10:12 pm
content: Quote from: SeanB on April 27, 2015, 12:56:36 pmPerfect. So something like thishttp://www.loctiteproducts.com/p/sg_ug_cntrl/overview/Loctite-Super-Glue-ULTRA-Gel-Control.htm

author: SeanB
author_rank: Super Contributor
timestamp: April 27, 2015, 01:29:42 pm
content: So they changed the bottle again, or this is the home version and not the industrial version. Same stuff different bottle.

author: Mamejay
author_rank: Contributor
timestamp: April 28, 2015, 03:11:25 am
content: Quote from: ozwolf on April 27, 2015, 12:44:37 pmI totally missed this comment Ozwolf. Yes they do look very similar. I will measure the membrane when I get home and see if one of these will do.Also I heard back from the supplier and he said he could sell me a new motor for about $40 but needed a picture of the motor to see if his spares will work.

author: Mamejay
author_rank: Contributor
timestamp: May 04, 2015, 02:36:50 am
content: I used the loctite rubber glue and now I am back in business. Seems to be working better than it ever has. Thanks for the advise everyone.

author: ozwolf
author_rank: Regular Contributor
timestamp: May 04, 2015, 03:07:43 am
content: Loctite rubber glue, hmmm, better get some of that.Ozwolf

author: Rasz
author_rank: Super Contributor
timestamp: May 04, 2015, 03:18:06 am
content: nice one

author: BradC
author_rank: Super Contributor
timestamp: May 04, 2015, 03:20:18 am
content: I'd still be looking for replacements. The fact it broke indicates it's either badly fatigued, contaminated or just crap rubber. The chances of it or its brother breaking again are pretty high.Unless it's a very lightly loaded part that was accidentally damaged, these days I work on the principle of glue being the thing that gets you back on the road while the replacement part arrives. If you just rely on the glue and don't have a spare in the box then when you really need it and at the worst possible time it'll fail again.

author: ozwolf
author_rank: Regular Contributor
timestamp: May 04, 2015, 03:56:31 am
content: Quote from: BradC on May 04, 2015, 03:20:18 amTrue.. +1

author: Mamejay
author_rank: Contributor
timestamp: May 06, 2015, 10:53:53 am
content: Did some more hunting around and contacted the manufacturer in China.www.china-zhongdi.comI asked if they had spares and they said no problem. I could have a set for free of the rubber caps just pay $6 shipping charges.Looks like I am in the clear and can get the old girl back to fairly new condition.