eheim 1048 rattling explained
 

after half a year of glorious watercooling i was thinking of doing some upgrading. my system was dd maze2, hayden rad, eheim 1048. to increase cooling capability i added a carheatercore, and a custom feed and bleed, all 3/8 tubing. the carheatercore i placed on top of my fulltower case at approx 60cm above pump, so the max height is not reached. after switching on the system my eheim rattled like it hadn't rattled be4. my thought was that my pump was dying on me. after browsing the forum here, i saw a post that said to let the eheim run from a kitchen sink with nothing attached. that made the pump run silent again. i removed one rad from the system and the pump was silent again, voila. what puzzles me is on the new vid from toms hardware they use a smaller eheim and add loads of stuff that i didn't even connect (gpu, chipset, hdd coolers). my guess is that i will need an eheim 1250.

Hint: try to glue the impeller to its shaft. The rattling you hear is because the impeller can almost make a complete turn around the shaft.
This is to protect it against gravels and small objects you usually find in an aquarium.
Unfortunately in our watercooled PCs it's useless and backpressure makes it rattle like mad.
You can use good epoxy or cyanolite.

Enjoy.
(Phew i posted this one 3 times today... hey ho pro/staff where's the FAQ :p )

(edit) i just saw you're from Belgium. Here it is in french if you missed it:
Essaye de démonter la pompe, et de sortir l'abre d'entrainement. L'hélice peut tourner presque complètement autour de l'arbre, et elle n'est retenue que par un taquet. Cela permet de protéger l'hélice contre les graviers et les petits objets qu'on trouve en général dans les aquariums.
Dans notre cas c'est inutile et bruyant.
Tu peux utiliser de l'epoxy ou de la superglue (ou aute cyanolitique) pour coller l'hélice Ã* l'arbre. Attends bien que ça sèche avant de remonter l'arbre !

(for english speaking ppl i just translated the first part).

thx gmat, your info might save me some euros...:p

the impeller, is that the screwblade as you would see the screw on a boat? im sorry for the lame drawing, but before i void my warranty i would like to be sure as to what i will be gluing.

Actually mag-drive pumps such as the 1048 are *meant* to be taken apart. Because you're supposed to replace the shaft (under aquarium conditions it takes quite a beating).
So don't fear and open the end part of your pump, it will *not* void your warranty.
Gluing the impeller will only void the warranty on the shaft :p
In the case you worry about that, extra shaft+impeller combos can be bought at pet shops or aquarium stores.
The difference with a boat shaft is in mag drive pumps, the shaft is not mechanically attached to the engine, but rather magnetically 'suspended' in a sealed housing.
I hope my ASCII art skillz are up to the task :p
Actually the shaft is usually centered on the inlet via a small attachment, so when you open the pump the shaft comes with it.
Do *not* glue this attachment or it will never turn...

i love forums, thx a mill gmat ;-)

your ascii art is definetely up to the task. for the sake of everyone i tried to make a better drawing. if there are still mistakes u name them.

gr33tz

Look @

http://www.stud.uni-hannover.de/~ang..._wak_eheim.htm

This page is German, but there are pics of the mod.

They dont glue it, they use teflon tape to fix the impeller to the shaft.

incredible i was thinking i was pulling off some almost never done stunt. off course some crazy germans had to do it first :-)

At this point I have used the glue tip on 2 Eheim 1048 pumps, and unfortunately in both cases the result was worse than before the glueing action. I am quite certain I did not do anything wrong...the impeller can pretty much NOT be misaligned, and obviously I did not glue the shaft to the rod.

Before you glue the impeller to the plastic shaft, the pump propels the impeller with a steady rpm. When you hold the top of the rod with your finger and activate the pump, you will see the impeller spinning evenly (meaning you will not get the "strobe effect" where it seems like some of the fins are standing still at a given position). After glueing there is a definite change in the rythm, now it DOES show the strobe effect, and the pump generates SIGNIFICANTLY more vibration.

So, in my experience, glueing the impeller to the shaft is NOT an improvement.

:(

It sounds to me like the teflon option would have been better: you might have thrown your props out of balance with the glue.

Yup, agree. I still have one original shaft/impeller combo left to tinker with, so I'll try the teflon option on that and report results.

As crazy as this sounds, I tried the teflon trick a long time ago. I just saw the tape and thought it was worth a try. It didnt work in my case, but I have a rio, not a eheim. My pump was rattling because of a different reason though...