Eisbaer LT pump failure

[Gishman]

After almost 3 years of operation Eisbaer LT pump start making horrible race car engine noises. At first it works as expected. Then in about an hour the noise starts. Rpm drops to about 200-500 rpm. Some time restarting the pump helps, but only for a brief period.
About a year ago I already had to service this pump. It has seised due copper oxide buildup. Luckily it was a quick fix. I have cleaned copper oxide resedue from the impeller and reasembled the unit.
This time there the pump is fairly clean.I have cleaned small amounts of copper oxide. The impeller looks good, spins freely, there is no noticeable play on the shaft.
But the issue remains. I would be grateful for any advice.

 

[Vanzin]

Hi,

it looks like your pump is broken and has to be replaced.

 

[Gishman]

Hi support,
Finally got a replacement pump. After filling the loop noticed higher than usual noise. There was some bouble noise, it is normal for a freshly filled loop. What worried me is a bit grinding sound.
Took the cpu block appart and niticed marks on the impeller. They appear near the shaft.
Here are two photos. I took one before assembling the pump and seccond after the dissasembly.

I suspect the impeller is sitting too low in its place and touching the cpu block housing near the intake
What should I do?

 

[Thomas_S]

@Vanzin - can you please check this!

 

[Vanzin]

Hi,

which pump did you purchase? It looks like that you have purchased a DC-LT 2 and not a DC-LT 2600. The DC-LT 2 is not compatible with older Eisbaer products.

 

[Gishman]

That is a disappointment.
I have purchased DC-LT 2. The other one was out of stock.
It looks the same, has the same dimensions and technical specs, has DC-LT branding. No mentioning of incompatibility in product description page or the data-sheet. I assume it also fits the same pump tops.

 

[Eddy]

@Vanzin
We have the pump on stock, please sent him one for free. I understand that he is disappointment about that.

@Gishman
Please sent an email to info@alphacool.com with your adress, a link to this thread and we will sent you one pump for free. But please write @Vanzin also a PN in this forum with your mail adress to verify your email. Otherwise someone will get the idea to write a quick mail to get the pump.

 

[Vanzin]

HI @Gishman

we will send you the replacement pump, O-rings and a new metall cover asap, so that you can replace it correctly

 

[Gishman]

Thank you support team. Just got the replacement pump.

The package got badly damaged by postal service. The pump looks intact. The metal plate got chewed up and the whole package was opened at some point. I blame our postal service.

No need to send any more parts at this point. My original metal cover is still in good shape.

Also while waiting I have managed to MacGyver the LT2 pump on to Eisbaer LT. And it runs great. The speed controller on the LT2 version is on another level. it is completely inaudible. On the old you could clearly hear the electronic buzz. And I had to throttle down the pump. It was the loudest part in my sffpc at idle. The new one I can leave at full rpm.

Perhaps a thicker O-ring could solve the compatibility issue. It is necessary to lift the version 2 pump in the socket by a small amount. Just a thought, I understand that it is probably a rear case and there are better things to spend engineering resources.

This is what I wanted to share. Have a good day