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Iwaki MDRLT 20 Mini Review

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method().man

Member
Joined
Dec 4, 2002
Location
Hell's Kitchen
With my new watercooling setup (pics to come when girlfriend finds lost digi-cam :mad: ), I decided to get the best parts out there. Just for kicks, I went for an Iwaki pump instead of the more run of the mill Eheim. Because I had purchased a block from Cathar (a highly restrictive block) and I had planned on getting a custom made vid card block in conjunction with a mammoth Lytron radiator, I felt that the enormous head that the Iwaki produced would help my system out quite a bit.

After running into logistic problems, I had to settle for a dtek heatercore avec shroud and I'm *still* waiting for my vid card block. That being said, I was still able to construct my watercooling system with the Iwaki pump since they are fairly easily found.

I must say, this thing literally ROCKETS water out of its outlet. the amount of pressure and head this thing produces has to be seen to be believed. In fact, when I first plugged in the pump in my bathroom, I was so unprepared for the deluge of water I would recieve that I was practically attacked by a jet of water that had richocheted off the bathroom wall and into my face. Yes folks, this thing makes an Eheim look like a siphon by comparison. Although the Iwaki produces only about 400 gph (about 200 less than the top of the line Eheim) it loses very little of its max pumping ability after 10 feet of tubing--because of this, in a watercooling loop after all the twists and turns caused by the blocks, radiators, etc., the water is still going at a pretty high velocity. Whether or not this will actually aid *your* particular wc setup depends on your components (high flow doesn't necessarily translate into lower temps as evidenced by numerous articles out there on the web). That being said, if you carefully pick your components out, the Iwaki pump can be quite an asset to your cooling setup.

The first thing that will blow you away when you see the Iwaki pump is the sheer size and weight of it. This thing really is a beast. It is encased in a painted metal cylinder that feels solid as hell. Seriously, your girlfriend could probably get a good workout curling this pump. If you have a mid-tower case, I would stay far away from the Iwaki as I cannot concieve of a way it would fit inside. With fittings, the pump will probably be around 9" in length--this, in addition with its 4" diameter adds up to one humongous piece of machinery. I have an ATC-710 case (same chassis as the wildly popular Chemning/Alien case) and I had to do quite a bit of hacking to mount it. I ended up losing my entire 3.5 drive bay just to fit it and it STILL blocks a good portion of my mother board.


PROS:

-Solidly built. Could probably survive a nuclear holocaust
-Enormous head. Loses very little over a wc loop
-Looks badass. I must say, the industrial look of it is quite appealing.

CONS:

-HUGE. I highly suggest a full tower case or even a cube to fit this mammoth.
-3/4" fittings. Getting adapters for this thing will just add more to its heft. Also, if you REALLY want to take advantage of this pump's power, you should probably stick to 5/8" tubing--I settled for 1/2" as I simply don't have the space.
-Expensive. At around 120-140 retail, these puppies ain't cheap.

*edit*

One thing that I think I should point out: there are two variations Iwaki makes on this particular line of pumps. One is the MDRLT and the other is the WMDRLT. The 'W' in the front means that the motor was made in America to help lower costs. The 'MD' appelation means that the motor was made in Japan. Generally speaking, the two pumps are identical except that the WMD series are slighlty longer and produce a little more heat than the 'MD' variation.
 
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method().man,

You need to start a website to post your reviews.

Thanks for the great info you have provided :D
 
Now I want one just to have the Ultimate Super Soaker. Wonder how this puppy stacks up to a fire hydrant.........
 
I think cathar said something about making a dif version of the WW for those with high head pumps like the Iwaki, do you have this version or the normal? And what temps are you getting?

BTW- Very well done review :D
 
JML said:
I think cathar said something about making a dif version of the WW for those with high head pumps like the Iwaki, do you have this version or the normal? And what temps are you getting?

BTW- Very well done review :D

Right now, my 2.4 PIV C1 is running at about 28-30 C under full load (about 1.68 v).

I was unaware that Cathar was exploring making a block for high flow pumps. I'll be sure to ask him about it :).
 
I beleve he is changing the jet so its more restirctive and higher velocity for the pumps that can handle it

and nice review! get pictures up!
 
I do have an experimental/more restrictive nozzle plate here for the higher head pumps (>5m head). I too was looking at grabbing hold of an MD-20 so I could test it properly. Basically looking at a near doubling of the nozzle jet velocity with an MD-20RZ. What benefits that provides is as yet unknown.
 
What adapters did you use to fit your 3/4" inlet/outlets?

I've just received a new Gen-X Mak 4 that pushes about 1100 gph with a maximum head of 6M(around 20ft). This thing is a monster! It's at least 9 inches long and weighs around 4 Kgs.

I'm thinking of getting Loc-Line's modular fittings for a 3/4" to 1/2" y-adapter to parallel cool the cpu and gpu and then to cool each line with a separate heatercore.

I've also concluded that this beast is not going to fit in my poor Lian-Li P-60. So any suggestions on an appropriate case and mounting would be highly appreciated.

Thanks!

P.S. Would super long IDE cables affect performance? I don't know how the normal cables are going to reach to the higher bays of a full-tower!
 
Wangster said:
What adapters did you use to fit your 3/4" inlet/outlets?

I've just received a new Gen-X Mak 4 that pushes about 1100 gph with a maximum head of 6M(around 20ft). This thing is a monster! It's at least 9 inches long and weighs around 4 Kgs.

I'm thinking of getting Loc-Line's modular fittings for a 3/4" to 1/2" y-adapter to parallel cool the cpu and gpu and then to cool each line with a separate heatercore.

I've also concluded that this beast is not going to fit in my poor Lian-Li P-60. So any suggestions on an appropriate case and mounting would be highly appreciated.

Thanks!

P.S. Would super long IDE cables affect performance? I don't know how the normal cables are going to reach to the higher bays of a full-tower!

I used stainless steel YOR-lock adapters (similar to swageloks) which are compression type fittings. That pump you got sounds like a real screamer :eek: .

Yeah, I would probably stay away from the LL case. If I were you, I'd look for a case that is both wide and tall: LL 7323, Chenbro Echo/Net, and YY Cube cases come to mind. This will give you a lot more elbow room to fit all your components without having to cram everything in. Although the case I have is fairly large (in the tall sense), some extra width would have definately been welcome.
 
I managed to get my Iwaki installed! I got the MD-15R off of ebay, brand new for $70. This pump is smaller than the 20, and flows 300GPH @ 0 head and has a max head of 3.4 meters, or almost 12 feet. Puts out 29W. This should be a better pump than the 1250 I have with a 2 meter head... and I got it to fit in the same spot as the eheim! Pics will come...
 
Wish I had room for one of those pumps. Until then, I'll keep searching for the very elusive "perfect watercooling pump" 8[)

peace.
unloaded
 
I have the WMD-30 RXLT...here are some pics

pump.jpg


pump_label.jpg


It is next to a 12" ruler in the first pic, and has 1" input/output. I am in the process of modding an Addtronics 7896a to fit it, and a whole bunch of other schtuff :), in, along with a few other mods hehehe :p. Also, I am building my own WC system based on the 1" tubing. Unfortunately, it will be a few months until Im finished, because of school and the enormity of this project. Patience is not my best virtue :eh?:

Edit: forgot to add, its rated @ 960 GPH w/ a max head of 13.5 ft
 
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loner said:
I have the WMD-30 RXLT...
It is next to a 12" ruler in the first pic, and has 1" input/output. I am in the process of modding an Addtronics 7896a to fit it, and a whole bunch of other schtuff :), in, along with a few other mods hehehe :p. Also, I am building my own WC system based on the 1" tubing. Unfortunately, it will be a few months until Im finished, because of school and the enormity of this project. Patience is not my best virtue :eh?:

Edit: forgot to add, its rated @ 960 GPH @ 13.5 ft :eek:
Actually it is rated at 960GPH at 0 head. Max head is 13.5 feet. This is not the best pump for computer cooling, but since you do have it... These are high flow LOW head pumps, we typically want high head.
 
Since87 said:


What waterblock are you going to use that with?

Im making my own...

nikhsub, I was unaware of that. I understand wanting high head, but if the system itself isn't that extensive (say only like 3-4 ft. in length altogether-thats what most systems are) does that make much of a difference?
 
loner said:


Im making my own...

nikhsub, I was unaware of that. I understand wanting high head, but if the system itself isn't that extensive (say only like 3-4 ft. in length altogether-thats what most systems are) does that make much of a difference?

It's not so much a matter of length of the tubing. (Although that matters too.) It's more an issue with the parts of the system that provide relatively high restrictions to flow, like the waterblock, the rad, and any 90 degree elbows.

To get a certain amount of flow through these restrictions requires a certain amount of pressure. (See Chart 1 of BillA's article.)

As shown from Bill's data, some of the blocks he tested require 3 meters of head to get 166 GPH through them, and that's not including the other restrictions in the system.

I would guess that this pump paired up with a very open block like a Swifttech MCW462-UH and a very unrestrictive heater core might give very good performance. (Might want to use two heatercores in parallel to get the flow resistance down more.)

If you want to use a relatively restrictive block similar to the Dtek TC-4, or Cathar's White Water, you would get better results with the high pressure (Z) MD-30, or even the standard MD-30.
 
My waterblock will not be really flow-restrictive, and I will do something with multiple heater cores, but I do see your point. Perhaps I could sell it on eBay and get the MD 55 RLT, 1080 GPH with 26 ft max head :D
 
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