Eheim Vibration

[ShadyOak]

I just completed my second WC system, this time using an Eheim 1250 inline with a res / airtrap. I've got the pump mounted on rubber grommets and the mounting screws also have grommets on them so that the pump mounting rails should be pretty well isolated. However, this pump still has an annoying vibration and low pitched hum.

I built an add-on wooden case to house the watercooling componets, and it screws on to the right side of the computer case. I've used rubber feet on the bottom of the case, and even with the whole thing sitting on a folded towel, I can still slightly feel the pump vibration on the floor.

Is it normal for this pump to vibrate so much?

I'm quite happy with the performance of the system. It uses a DD MazeII on the CPU and another DD block on my Gainward GF3. The radiator is a 4 pass 5 1/2 X 11 heater core recycled from the junkyard for $7.50! Two 120mm aluminum Sanyo Denki fans cool the rad in a surplus shroud that fits beautifully and has rubber isolation mounts for the fans. I can switch select one or both fans and drive them at 7 or 12V. Very quiet even at full speed.

My XP1600+ is at 1610mhz in a Soyo Dragon+, and I haven't seen the temp go over 40c yet (stock on-board thermister).

If only that damn pump didn't vibrate so much! Any ideas?

[Brad]

I don't think that sounds like a normal eheim, most people say they are much quieter than that.

as for mounting it in a way to stop vibration, get the big sized bubble wrap, glue it to the bottom of the res, and glue the pump to the top of the bubblewrap

[decodeddiesel]

Those rubber gromets are lousy for isolating vibration. In fact all rubber just doesn't absorm vibration that well. I have noticed Eheims can be very annoying when they are left to resonating the case due to poor vibration isolation. I would try some open call foam from a package or something softer than rubber. Note: Neoprene also does a poor job isolating vibration.

[redleader]

Mine does the same thing, so I think its normal. My current isolation really sucks, I'll have to try the bubble wrap.

[zoson]

It sounds normal, my 1250 does the same thing. I cut up a standard thick mousepad, it's very very porous rubber and worked like a charm. Complete silence.
http://pictures.zoson.net/
-Zoson

[Haddy]

ive herd if theres some back pressure that the pump will be a lil noiser then normal.....

[ShadyOak]

Thanks for the replies and suggestions. I'm relieved to hear that I don't have a bad pump!

The mouse pad and closed cell foam both sound like great ideas. I also have an idea for using a few pieces of leftover silicone 1/2" hose. I would cut notches out of each end for screw holes to attach to the case. The pump rails would be mounted to the hose via machine screws / nuts. The nuts would be slipped in through the open ends of the hose to catch the screws coming down fron the top. Kinda hard to explain. I'll try to get something figured out this weekend and post a few pics.

Haddy - I'm using half inch hose, 1/2" copper elbows and 5/8" T's so I really shouldn't have too much back pressure. Both blocks have 1/2" fittings also. But, it's a looooong passage radiator.

[Brad]

if you take the pump, put it into your kitchen sink, and turn it on (fill the sink up first), it should be silent. Even my rio's are silent this way

[ShadyOak]

One of the shortcomings of my setup is that it's a cast iron baitch to bleed air out of the radiator. My res / airtrap is actually a bit lower than the top of the rad, and air likes to settle in to the top chambers where the fittings attach.

It's a real pain to empty the system, do maintenance, and refill / bleed it out. Not enough time during the week, so I'll tackle it on Saturday and see how quiet it runs submerged.

[ShadyOak]

I couldn't wait for Saturday to do something about the vibration, so I got home from work tonite, unscrewed the grommetized mounting screws, and slipped in some relatively thin pieces of closed cell foam under the pump. Huge Difference!!! It is really quiet now. The pump just sits on the foam - no screws. The tubing more or less holds it in place and I don't plan on moving the system around. decode diesel, you really nailed this one!

While I was at it, I re-did my case fan configuration a bit. I added a side case fan (mounting bracket was already there), switched the front and back fans to some high flow Panaflows and ran 'em at 7v. The case fans are now quieter and I think the total airflow is about the same.

Also, for some reason my CPU temp via MoBoMon dropped about 3 degrees C! It might be that the side case fan that is blowing right on the waterblock is cooling off the Soyo in-socket thermister. I know these things are not very accurate, but I haven't been inclined to add a Digital Doc.

Anyway, I'm really pleased how these last few tweaks worked out. Thanks!

[DodgeViper]

I am using open cell black sponge rubber foam and my 1250 is silent with no noise at all. I placed the foam across the entire bottom and have insulated both sides and top of the case as well. If you look closely you can see the foam on the back wall of the case.

[Jim]

I picked up some of this foam water pipe insulation at the hardware store. It is for 1/2" or 3/4" pipe and cost $1.19 for a 6' length. The material has good density and is about 3/8 to 1/2" thick.

I spread it open, cut a piece off long enough to fit the base of the Eheim 1250 and glued it to the pump with rubber cement.

Huge noise and vibration reduction. I did bolt the pump to the bottom of the case with 8-32 screws and wing nuts. I still can hear a hum and feel very slight vibrations, nothing significant.

Jim

[ShadyOak]

I still have some vibration with the pump just sitting on the thin foam, but it's not too bad. The next time I drain the system I think I'll try the water pipe insulation. I've seen this stuff before and it is quite dense. Now I gotta buy some rubber cement. Geez, if I keep at this hobby, I'm going to have every adhesive known to man!

[DodgeViper]

What you want is a neoprene sponge. You want the rubber too absorb the vibration. The hose material in the photo is not forgiving. The material found on the bottom of mouse pads is close to neoprene sponge although it’s still a little to dense and not very thick. The stuff I am using is ½” thick and absorbs all vibrations. I even insulated my entire case with this foam.

[Haddy]

Originally posted by DodgeViper
What you want is a neoprene sponge. You want the rubber too absorb the vibration. The hose material in the photo is not forgiving. The material found on the bottom of mouse pads is close to neoprene sponge although it’s still a little to dense and not very thick. The stuff I am using is ½” thick and absorbs all vibrations. I even insulated my entire case with this foam.

what did u buy like 50 mouse pads or did u find a place that just sells the foam

[ShadyOak]

Yeah, where did you find 1/2 " neoprene sponge? It sounds like it would work great, but how did you get 1/2" thick material in the top and sides of the case? I don't think I have that much clearance in my case.

[Jim]

Quoted from DodgeViper: "What you want is a neoprene sponge. You want the rubber too absorb the vibration. The hose material in the photo is not forgiving. The material found on the bottom of mouse pads is close to neoprene sponge although it’s still a little to dense and not very thick. The stuff I am using is ½” thick and absorbs all vibrations."

Dv-

This stuff does compress when you put pressure on it eg, when I bolted the pump to the floor of my case. It has quite an "airy" consistancy. It is a quite different substance than is commonly used on the A/C lines in you home to insulate the line which is thinner and less airy. Also Mouse Pad is much denser and compress very little compared to this stuff I am using.

But, too many sections of this insulation would needed to be positioned side by side to insulate an entire case IMO, but it could be done.

Jim

[DodgeViper]

My Antec SX11040 both side plates have an area that I was able to cut the foam and tuck the foam under metal to hold the foam in place. I also used two sided tape in the middle to hold it flat. The top of my case has plenty of room.

CLOSED CELL SPONGE RUBBER: Very dense and durable. Used for gasketing, sound barriers, weatherstripping.

OPEN CELL SPONGE RUBBER: Highly compressable and resilient. Used for cushing, packing, insulating.

Now for the bad news, OPEN CELL SPONGE RUBBER is not cheap. Most refrigeration shops carry a lower grade of foam that will work for your application and for a lot less money.

This is the softest of all rubbers,

Click

McMaster CarrCLICK

[Jim]

This pipe insulation has a greater amount of air pockets in it than a mouse pad.

Here are some more images of the material. It can be easily compressed with my fingers to under 1/8" thick. It has a "shiny" appearance, which distinguishes it from other types of insulation used in HVAC applications.

See images illustrating the cross section of the material, full of air pockets.
Jim

[DodgeViper]

Check out this page. Go to the Supper Soft Neoprene Rubbers, CLICK

Also if your bolting the pump to the case your introducing sound and vibration to the case. My pump is not bolted, but sits on the sponge rubber. Pump does not move at all and is very quiet. My mouse pad is very soft and would absorb vibration, but the only problem it's only 1/8" thick.

That pipe insulation is a ployurrethane or styrene foam and not good for absorbing vibration.

[redleader]

I wrapped mine in bubble wrap like suggusted. Works 10x better then plain rubber.

It still vibrates a little, but not too much that its annoying. I'm going to grabe more from work on Tuesday and see if that helps.