Defect In Dragon Pumps

[SCVkoiboy]

About 2 years ago, I bought a Dragon pump and installed it with my new pond. The Dragon pump was sucking in air, but I wasn't sure if it was my pipes or the pump. I contacted William Lim at a koi show and he told me he had problems with his Dragon pumps whereby the molding process failed to inject enough material and, therefore, the rim of the basket was sometimes uneven and air may get into the pump due to an uneven lip. He told me to check the rim and get back to him. I checked the rim and noticed that the inside of the rim was lower than the outside (I placed a straight edge across the center of the basket and noticed the gap on both sides along the inside edge of the rim). Is it supposed to be that way or is that a design flaw?

I took the pump to William Lim's shop and he tested it by placing the pump below a large container of water so the water would flow down towards the pump about 2 feet. The output side was only a foot or so and just squirted out into the basin. He said the pump was fine and did not suck in air (I question his method for testing). I bought a new gasket and a new union as suggested by William.

When I got home and hooked it up, I used the new union to run a pipe straight into my settling tank with a single pipe (no joints). The output was hooked into the same old pipes. This, I figured, would tell me if it was my pipes or the pump. The pump again was sucking in air.!!!!!! I then hooked up a Performance Pro pump to the exact same pipes (original intake and output) and it runs fine. NO AIR!!!! When I contacted William Lim, he refused to warranty his pump and said his pump worked fine.

Has anyone else had a problem with Dragon pumps or dealing with William Lim? I feel like I got scammed!!! I think he intentionally hooked up the pump so the water was gravity fed to the pump and pumped straight out thereby creating no strain or pressure on the pump. In the real world (at least my system), the pump had to push water through a bead filter and through 50 feet of pipe with a 5 foot rise. I think the pressure on the output side may have something to do with the reason the air gets sucked into the basket area. Does anyone have any thoughts about this? I question William's honesty and integrity for another reason. When I was at his shop, he hooked up his pump and a competitor's pump to demonstrate how his pump is better (or as advertised). They were each hooked to a flow meter. His pump did pump better than the competitor, but when we looked at his specs for his pump, the flow meter indicated his pump did not pump as he advertised. He tapped the flow meter and told me it was broken! How stupid do I look!

I will never buy another product from William Lim. I don't really know if his products are good or not and I am open to any suggestions about my pump problem, but I believe he has horrible customer service.

Has anyone else had a problem with him or his products or is it just me? If it is just me and someone can explain my pump situation, I will gladly apologize to William. Until that time, buyer beware!!

[kingkong]

I would love to see a picture of the un-level leaf trap port. It is hard to imagine how the molded frame could be that incongruous. To test that, I would un-screw lid, leave the O ring in pump frame then put a 1/4 inch plate of clear plexiglass over the entire opening with some water on O ring. Press down on plate slightly to see if there is proper seating 360. If that appears to be ok, the channel the O ring seats in must be compatible with O ring or visa versa. The thing I do not understand is if the impeller is creating all this vacuum during operation, the more the better. It should make the lid pull tighter against the O ring 'seating' making it imposible for air to pass by. It almost sounds like there is some problem with wall thickness of pump housing or screw lid that is disorting under vacuum suction which would be very unusual. The O ring is 'gauged' wrong or injection mold 'shoulders' that need to be milled for perfect mate with lid. I am going to check one out, this has gotten curious.
As far as the rim being lower on inside of O ring channel would depend on design. Does the lid have the same configuration only opposite so it mates and seats properly with frame. Take out O ring and put the two together. That shallow inside shoulder of rim could also distort the O ring under vacuum causing a seating problem.

[kingkong]

If there is an impeller design problem, the pump can cavitate from vaporization, air ingestion (talked about), internal recirculation, flow turbulence and vane passing syndrome. I was always tempted to exchange impellers with pumps but was always cautioned doing so due to strict manufacturer criteria.

[dannyp]

Originally Posted by SCVkoiboy

About 2 years ago, I bought a Dragon pump and installed it with my new pond. The Dragon pump was sucking in air, but I wasn't sure if it was my pipes or the pump. I contacted William Lim at a koi show and he told me he had problems with his Dragon pumps whereby the molding process failed to inject enough material and, therefore, the rim of the basket was sometimes uneven and air may get into the pump due to an uneven lip. He told me to check the rim and get back to him. I checked the rim and noticed that the inside of the rim was lower than the outside (I placed a straight edge across the center of the basket and noticed the gap on both sides along the inside edge of the rim). Is it supposed to be that way or is that a design flaw?

I took the pump to William Lim's shop and he tested it by placing the pump below a large container of water so the water would flow down towards the pump about 2 feet. The output side was only a foot or so and just squirted out into the basin. He said the pump was fine and did not suck in air (I question his method for testing). I bought a new gasket and a new union as suggested by William.

When I got home and hooked it up, I used the new union to run a pipe straight into my settling tank with a single pipe (no joints). The output was hooked into the same old pipes. This, I figured, would tell me if it was my pipes or the pump. The pump again was sucking in air.!!!!!! I then hooked up a Performance Pro pump to the exact same pipes (original intake and output) and it runs fine. NO AIR!!!! When I contacted William Lim, he refused to warranty his pump and said his pump worked fine.

Has anyone else had a problem with Dragon pumps or dealing with William Lim? I feel like I got scammed!!! I think he intentionally hooked up the pump so the water was gravity fed to the pump and pumped straight out thereby creating no strain or pressure on the pump. In the real world (at least my system), the pump had to push water through a bead filter and through 50 feet of pipe with a 5 foot rise. I think the pressure on the output side may have something to do with the reason the air gets sucked into the basket area. Does anyone have any thoughts about this? I question William's honesty and integrity for another reason. When I was at his shop, he hooked up his pump and a competitor's pump to demonstrate how his pump is better (or as advertised). They were each hooked to a flow meter. His pump did pump better than the competitor, but when we looked at his specs for his pump, the flow meter indicated his pump did not pump as he advertised. He tapped the flow meter and told me it was broken! How stupid do I look!

I will never buy another product from William Lim. I don't really know if his products are good or not and I am open to any suggestions about my pump problem, but I believe he has horrible customer service.

Has anyone else had a problem with him or his products or is it just me? If it is just me and someone can explain my pump situation, I will gladly apologize to William. Until that time, buyer beware!!

Another view on William Lim customer service. Yes an apology may be due.

Tom C vbmenu_register("postmenu_90477", true);
King of PondPetUSA
Join Date: May 2004
Posts: 485


Something about Mr. William Lim
I know some of you think I was hard on William on his "Pick on it" post. But William want to know what people think, so I told him.

With all of that said, lets talk about Mr. William Lim.

William build a pond about 10 years ago for one of my customers. A few weeks ago the Sequence pump went out on the pond. Yes the pump was 10 years old. The customer needed a new pump ASAP because this pond is way over stocked, and all I had was Performance Pro pumps in stock at the time. I went over and the customer wanted a Lim pump. So the next day we had a Wave pump on the pond. The pump was put on and the customer loved the extra flow. Four days later I got a call, the pump wasn't pumping like it was. On the phone to William and he said it couldn't be the pump. I went back out and played with the pump a little and the flow was back. Three days later I got another emails saying the flow is about half again. Back on the phone to pick Williams brain. He told me check the voltage coming out of the box that the pump is hooked up to, he also said he thought something might be in the drain lines. I want back out to the customers place and the voltage was fine. Next thing I know William is making a 1 1/2 hour drive to bring a larger pump to try to suck the stuff out of the drain. We hooked up the pump and leafs rocks and other things came out. He left the pump run over night on it, and then I went back the next day to hook up the other pump. The customer also cleaned out the drains with a plumbers snake and pulled out a lot more stuff. Now the pond is running great again.

I just wanted to let you know what kind of customer service William Lim does have. It was after dark the night he came out with his wife and he went way out of his way for me and a customer of his. So my hats off to you Mr William Lim and think you.

Tom

[SCVkoiboy]

I spoke to Steve C who advised me that he was representing William Lim and that William had agreed to send me a new pump if I sent my old one to Steve to be tested. Being skeptical and believing that this was just a way for William to claim to have the pump "independently tested" and for them to tell the world that there was nothing wrong with the pump (and thereby clearing his name), I asked that William come to my home (an hours drive) to see the set-up and tell me what was wrong with my system. I suggested that it would be best to have it done during our koi club meeting so there would be witnesses. Steve declined so I agreed to send my pump to him after I received a new pump from William.

I received my new pump and hooked it up today to the same plumbing as the old Dragon pump. IT WORKS GREAT!!! No air in the line and no cavitation. Yahooo! I checked the level of the lip on both pumps and the old one definitely has a greater slant than the new one. I truly believe that there is a design flaw in the dragon pump and air was getting in between the lip and the cover.

When I receive the shipping paperwork, I will send my old pump to Steve for testing. I asked Steve to post his test so everyone can see the results and he agreed. I want to thank Tom C and Steve C for offering to get involved in this situation. I am still very disappointed that William didn't just back his product and only decided to send me a new pump after realizing the bad publicity he was getting. His customer service really is horrible! In any case, I am anxious to see Steve's test results and hope he will do an honest test of my old pump.

[Tom C]

Brian I'm glad to hear you got the new pump and it's working GREAT. Like I told you before, it's the pump not your plumbing. I can't wait to see what Steve finds. I'm sure Steve will be up front with all of us.

Mr. Lim, I'm sorry it came to all of this on the board. You left me and Brian no way out on this one. I'm also sorry you lost another dealer (me). Next time one of your dealers tells you he's having problem with a pump, please don't blow him or her off by saying it's the plumbing. Things can go wrong with any brand of pump.

DannyP, I do stick to what I posted on that other thread. William gave that customer GREAT SERVICE. And I have to say you are right with and apology. William should call me and the customer on this issue with the Dragon pump and apologize for what he put both of us through. You know that will not happen. After Steve posts that this pump did have a issue, are you and the other people that were bad mouthing me going to apologize to me for trying to get me customer a pump that works right? I don't think so, because they don't have the balls to say, sorry I was wrong Tom.

Tom

[schildkoi]

Brian,
I am glad the new pump has arrived, working well and you are a happy camper Just to set the record straight, I am NOT representing William. You can trust that my tests will be up front and factual. My name and integrity level are things I hold dear to my heart and would never jeopordize. Yes, I am a Lim product supporter and have been for many years. But when I find something wrong, I have no problems telling william or anyone else and William knows this. After I get done with my tests, I am shipping the pump off to Roark for him to put through additional test and hopefully verify whatever findings I determine. Both Roark and myself have always "called'em as we've seen'em".

I will make a note that it is pretty standard practice to bench test pumps and base decisions off of these tests. But often times bench testing doesn't tell the whole story, especially when circumstances are found to be substantially similar to other problems when they turn out to be systems issues instead of pump issues. In other words, historical data indicates one thing so you make the decision based on that...when there could still be possible other issues that only factually surface using non standard tests (other than bench testing).

As soon as possible after that I will present my results/opinions to Roark, William and Brian.

Steve Childers

[Rich L]

Hi Steve,

About 6 or 8 years ago I saw one of Lim's setups for comparing pumps. The 'other manufacturers pump actually had a smaller size return pipe that the Wave. Didn't trust his statements for quite a while.

Added to that, is the performance curve he's used for his 1/4hp pump for years. It's Not on the same scale as the sequence & others so the extremely low head isn't apparant when compared to the others by hobbyist with little experience.

I heard him recently when he made some promises to a hobbyist while she was considering buying his new pressurized microstrainer. He said he would give her a more powerful pump for free if her pump didn't drive his unit. She ended up paying for the larger pump. Added to that was the workmanship. There was a meter at the output of the unit. I asked him why it didn't show any pressure and he avoided a direct answer and said If you ever see a pressure on that meter the unit has failed. When I had the unit apart I found the meter didn't connect to anything. It was just mounted in a tapped hole with no outlet. I still wonder what that was about.

The only people I see with complimentary comments are dealors. Dealors are likely to move more pumps if he performs well for them.

It's disappointing because now and then he comes up with an item that stands out. One thing I do admire is his willingness to get in there and MARKET his products. That's the main difference between a successful wholesaler and a struggling pond contractor.

[schildkoi]

What can I say? I am not a dealer and I have had nothing but positives with Lim Pumps. That's not to say that things cannot go worng with any product either. As for performance curves? His are accurate and in the tests I've performed the pumps perform better than the curve...I can't say that about other brands. His performance curves are pretty standard format, almost the identical format of the performance curve layouts for Peerless firepumps. Head/Psi along with flow, not really rocket science.

As far as "promises", not fair for me to comment, I wasn't there. I haven't taken apart the pressurized settlement tank either, but I'll take a look at one and see what I find.

Steve

[Tom C]

I also think his performance curves are right on. I have been at his place a number of times when we tested them. Always they were right on. Lim does do something different than most other pump makers. He shows a real low head pressures for his ratings on his pumps. This is a way to market them to people that don't know enough to look at head pressure. If you're looking for a pump don't just look at the gph on it. Look at the head pressure and the gph. Each pump maker will have a performance curve for his pump. Look at that, based on your set-up. If you ask me it's a great way to sell a pump when someones doesn't know what to look for in a pump. But his rating are right on from what I have seen.

Tom