Monday, May 12, 2008

Waterpik WP 360W disassembly


My Waterpik started to go down hill a few months ago but it was still usable. Now it's making horrible grinding noises that I just can't stand anymore. It's time for it to go under the knife...

As you can see, on the left is the fully assembled Waterpik. To begin the disassembly, remove the tip then detach the water reservoir from the main body.


Gently squeeze the reservoir cap and the top of the body to snap out the blue part.










The reservoir as shown separated from the body.













Remove the swivel cap using a flat head screw driver blade. It will pop out with a little prying all around.











Here is the end without the swivel cap.












Remove the two screws on the bottom of the body and slide the gut of this thing out.












Here is the gut separated from the body's shell!













I found out that the pump gear was just a little worn down and needed to have something that push it to the motor main gear. I added a little bit of tape and hot-glue to serve as a backing to the pump bracing arm. This will help push it against the motor main gear when assembled.


Here is the closeup of my fix! It works fine once assembled. Before assembly however, I put some Vaseline on the gears for extra lubricant and some on the motor housing and electrical area for extra insulation against moisture.

42 comments:

Gregg said...

Great procedure and diagram! Thanks to your diagram, I was able to take mine apart to figure out what was wrong with mine. (The motor itself had seized up, but I was able to work it free once your handy diagram showed me how to pop open the case.)

aquafolium said...

thank you....who ever you are, i love the internet!

jones.neil said...

can you please ...please tell me what the output on the Waterpik wp360 charger is and is it pos in the center.

thanks in advance

Tomsim said...

The label on the charger shows:

output: 3V DC 100mA
Negative outside, positive center

Hope this help.

Tomsim said...

My Waterpik finally died for good last week. The cause of death is drained battery because it can't be charged anymore. The center conductor of the power plug corroded away! All of you out there, keep water out of the charging plug!!!

Anyway, I took the thing apart to repair the charging plug but the motor and its electrical terminals were corroded badly and fell apart as I tried to clean them :(

So altogether, it lasted for around 2 years. I got a free replacement after the first year (the switch failed to hold) that I'm starting to use now. The $22 spent is well worth it. (it's $29 at AMZ now)

Edgar said...

Very useful description! I own a different model, older and bigger one, with reservoir, water cable and a kind of valve (yours is compact, single piece). With the time (8 years old waterpick), the water cable has broken, and I could replace it by a new one after opening, using your description. Thanks a lot.

A. Thomas said...

I couldn't figure out how to remove the shell and then I found your post and *voila* removed the swivel cap.

My Waterpik was getting weaker and weaker. After oiling the moving parts, it's like new again. Thanks!

Egosumabbas said...

Thanks, you're a lifesaver. Mine stopped pumping and made a whining noise, which made me suspect that something was knocked loose. Without your instructions I would not have realized to remove the retainer at the top in order to slide the motorized assembly out. Once opened up, it looked like the motor wasn't making contact with the main gear. I didn't have to do all the extra work you did however, all I had to do was tighten the screws next to the motor to get them in contact again. Put it all back together and works like a charm. Thanks again!

Ben said...

Thanks for the photos! I'm planning on replacing the battery in my wife's waterpik.

Is that a AA size rechargeable?

Tomsim said...

Ben, it's not AA size. The part number is PN 37059-7. I found an entry for it on Amazon but it is for the 350W model. Maybe they share the same battery?

Walter said...

Thanks a bunch. I have the same model and problem as you did, but I was stumped on the disassembly because I did not think to pry off the cap on top.

errol-squires said...

Waterpik 360 Battery
I have been advised by waterpik never allow the battery to become fully discharged as it will shorten the life of the battery
I thought that batteries worked better if charged and discharged with NI-MH batteries
Is it better to charge it after each use and certainly before the battery goes flat

errol-squires said...

Hi does anyone know if these batteries will fit the waterpik 360 as they are easily and cheaply available on auction sites.

Look forward to your reply.

Features
• Capacity: 1000mAh
• Voltage: 3.0V
• Rechargeable Times: Up to 500 times
• Size: 33.5mm(Length ) x 17mm(Diameter )
Package Contents
• 100% Brand New
• 4 x CR123A 3.0v 1000mAh Rechargeable Lithium Batteries

Tomsim said...

The battery compartment dimension is 65mm long 22mm wide. The CR123A will fit but I think it will not work because it is lithium based. This device's charger has no electronic control so I think and can only work safely with Ni-Cad battery.

Tal said...

Thank you very much, it was very helpful in fixing my waterpik, i had problem with the big plastic gear. With help of wires i pressed the gear twords the motor. FIX.
thanks again.

Merrell said...

Thank you very much for the great description of disassembly. The retaining ring had me stumped too.
FYI, the markings on my battery are "Sanyo 2KR-1000SCL, 2.4v, 7H"

metalmorphasis said...

In any case, make sure you use "NMH" battery only!

Supa DJ said...

Thanks for the info dismantling this thing. After opening it up I saw that the gears were not connecting. First I tightened the screws but that did not work I then used a small wire to wrap the motor gear and the plastic gear closer together. Thanks for that tip from "Tal". The world is a better place when we share knowledge!THANKS ALL!

drew drew said...

Great step by step of taking it apart :) My problem was with the cog wheel not connected to the motor cog wheel. Put I fixed it! Very helpful!

348 said...

Great procedure. I bought mine 8 months ago. Walmart wouldn't take it back without the receipt. (what guy keeps the receipt..lol). Anyway, the thing stopped pumping. Took it apart, dried it off, cleaned the connections, tightened everything up and put it back together. Battery might be shot since I drain the batt almost every charge. Seems to be pumping away happily for the moment.

jonagin said...

Hi. I have had two rechargeable Waterpiks and each one only lasted a year before the motors packed up. Anyone know where I could get replacement motors?

Tomsim said...

It's probably going to be hard to find a replacement motor. I don't see any part number identification on mine. I think this thing has a 2 years warranty. I would call the company for a replacement if you are still within this time period.

mangroy said...

Very helpful post. I was trying to pry open the water reservoir with my swiss knife, waiting for something to snap, when I decided to give the net a try. And viola! your post was such a big help. Dropped my unit the other day, I simply had to tighten the screws holding the motor to the pump gear. Again many thanks!

jonagin said...

My Waterpick would no longer charge as the charging socket had corroded pins. I dismantled the unit and replaced the socket with a short cable (about 30cm) soldered to the switch and battery connections (I discarded the old socket cables). My new cable, I threaded through the old socket aperture and sealed with clear silicon. This new cable had a suitable socket end into which I now plug the charger. A dramatic improvement: I only have to charge it once a week now! The short extension cable does not impede use.

michael said...

I just replaced the motor on mine with one of these from ebay I can verify it is a PERFECT replacement "2mm Shaft Diameter 6V 7000RPM Mini DC Electric Motor"

http://www.ebay.com.au/itm/160676211131?ssPageName=STRK:MEWNX:IT&_trksid=p3984.m1439.l2649#ht_2573wt_1068

hope this helps someone else

Tomsim said...

Good to know about the motor. You can find it on the US EBay site too.

Not Just Tourists - Ottawa said...

Great stuff, guys (& gals?!)!
The power seemed to diminish with water in the reservoir. Not sure if it's the battery or what, but all the info provided here has been wonderful. Have ordered a 2-AA holder (NiMh, for sure) from eBay. Can't hurt... Will post again with results. Thanks to all!

Deadred said...

Excellent post by OP.
I have the same issue with my 3yo+ WP-360W as @Not Just Tourists where without any water in the unit, it sounds normal, but once it is filled with water, the motor slows right down and the water pressure is not really doing its job.
At first I thought it might not be charging because of possible corrosion on the charger connector, which looked quite dull. I managed to strip the unit down [before coming across this page] and gently clean the connector pin and tab using a sliver of wet&dry paper and a tiny screwdriver blade. I left this to charge overnight, but the result was a disappointing no change to the [lack of] performance. I now suspect the Sanyo 2KR-1000SCL NiCd cell pack has seen better days, even though my multimeter is showing over 2.5 volts, I think the actual power is sub-optimal. I have googled that Sanyo model [how I found this page], but not found it to purchase a replacement. Thanks to @Tomsim who pointed to the Amazon item. It appears to be made up of two 1.2 volt 4/5 Sub-C NiCd cells. These are fairly easy to get hold of online and priced ITRO £5 the pair. You will also need to be a little skilled in soldering to take advantage of this option. At 1/10th the cost of buying a brand new WP from a store, this is where I see myself venturing.

L6Group said...
This comment has been removed by the author.
tofudev said...

Thanks for the post. couldn't fix it without this post.

severov said...

Thanks! It works! :-)

Glenda said...

Can't find the waterpik charger, but have a Nokia charger that has a pin that seems to fit. Any idea if I can charge the waterpik with a non-Waterpik charger like the Nokia? Thanks in advance!

Deadred said...

@Glenda, my AC/DC Adapter has an output of 3V at 100mA with the round plug having a positive centre and the outer core negative. If your phone charger is close i.e. 3V with +ve centre and the current somewhere close to 100mA then it should be okay.

Deadred said...

Well it appears it has taken me a year to get around to trying to fix my Waterpik - but I did fix it! FAULT - Waterpik runs okay when dry, but lacks pressure when filled.
SOLUTION - Replace the batteries with two tagged 1.2 volt 4/5 Sub-C NiCd cells. I got mine in the UK from BatteriesPlus http://batteriesplus.co.uk/acatalog/4_5_Sub_C_1200mAh_NiCd_Tagged_battery.html . NOTE - Moderate soldering skills required and a tight fit on the overall length when ready to fit, but it does go, and the innner rails in the outer case stop any bowing, so all is good.

Glenda said...

follow-up to my question above about using a Nokia charger on the Waterpik - The Nokia charger reads output: 3.7V/340 mA (hmm, seems far from your charger at 3V/100 mA) - Do you think it will wreck it? Also you mentioned a positive centre ?? - what should be positive - the pin? And how can you tell? Thanks -

Deadred said...

Yes I agree that the phone charger is a bit too much voltage and current compared to the original charger. It is possible you may damage the batteries in the Waterpik. My advice would be to not use it. Yes, you are correct in that the inner annular connection of the charger that mates to the pin of the Waterpik is the positive connection. The outer metal part of the charger plug is therefore the negative connection. On my AC/DC Adaptor (UK region 3-pin) above the socket pin that would be for earth there is a symbol identical to the 'positive polarity' one that is about half way down the page on the left hand side found here: http://electronics.stackexchange.com/questions/33968/how-to-tell-polarity-expected-of-a-dc-barrel-jack

For completeness, the markings on my adapter are -
Model: B030010D21
Input: 230V~50Hz 35mA
Output: 3V=100mA 0.3VA
note the = character is as near as I can type to be the symbol for DC!

Tomsim said...

How about go to Goodwill, pick up a charger that match the spec you need then swap the end plug with one that fit the Waterpik.

Deadred said...

If you are in the USA, I saw item #171027311303 on ebay for a used adaptor that was within spec. Only that it seems pricey, and you would want to check that the outside diameter of their plug is 3.5mm

monstercolorfun co said...

what a great post! chances of finding a wp 360 dissassembly and fix... omg!

George Taylor said...

I had worked out how to disassemble my and was looking for repalcement battery when I came across your procedure, good one!
I located a supplier for the batteries (2 off) they are quite standard. You need a soldering iron and some heat shrink (tape will do). I paid £2.60 (each) from CPC.
Link:-
http://cpc.farnell.com/gp-batteries/gp125aah1a1p/battery-ni-mh-tags-aa-1-3ah-1-2v/dp/BT00172?Ntt=bt00172

mac mcquin said...

Great explanation of how to dissemble the AquaPik!

We had bought my wife's unit in Wal Mart in spring 2013 but by summer the batteries looked like they were giving out so I bit the bullet and opened everything for inspection. I've now replaced the 1300mAh NiMH cells with a couple of 2300mAh I had kicking around - not new but they should do fine. I also swapped the 110 Volt charger for a redundant 100/240 Volt minidisc charger and spliced on the original odd-shaped plug to its output wires.

The output voltage is a little higher (at 3.5 Volts) than the original's but I figure it won't harm the replacement cells as it's charging at about 600 mA so I'll get my wife to charge the unit overnight whenever the cells run out of juice and see how things go from there.

Previously I'd had to use a 240 to 110 Volt dropping transformer to plug in the US lat pinned charger but now the standard 3 pin UK plug is much simpler and there's no more infernal buzzing from the dropper transformer!

Pity the manufacturer didn't supply a universal voltage charger as they're ten-a-penny nowadays and likely little more expensive than the original simple transformer with its a/c output and internal diode in the case to provide d/c charging current.

mac mcquin said...

I got it wrong. My replacement charger, whose voltage was around 3.5 Volts on charge load, pumped 600mA into the replacement batteries which soon made them very hot - it was too high a charge for the cells.

I've now used an ancient, multi-votage charger which gives around 250mA and should be much closer to that of the OEM charger.