Gast 0523 Questions

[Tom Albrecht]

I just picked up a used 0523 pump.

Should the pump come to a complete stop when I cover the intake port with my finger?

What would be the best pump test method?

 

[Dwight R Rutherford]

No, the pump should not stop when the intake port is blocked. Best way to test is to hook up a vacuum gauge and see how many inches of mercury the pump is drawing. Depending on the elevation you live at ( there is a calculator online ) the pump should be drawing around 25 inches. I live at 176 feet above sea level, that's what my Gast draws. Hope this helps.

 

[Tom Albrecht]

No, the pump should not stop when the intake port is blocked. Best way to test is to hook up a vacuum gauge and see how many inches of mercury the pump is drawing. Depending on the elevation you live at ( there is a calculator online ) the pump should be drawing around 25 inches. I live at 176 feet above sea level, that's what my Gast draws. Hope this helps.

I didn't think so.

When you say it should draw 25" do you mean it should be drawing that with the intake port closed? I believe that's what my old one did.

 

[Tom Albrecht]

Looks like it's time to see how well the Ebay 100% guarantee works.

 

[Dwight R Rutherford]

My answer was not as clearly stated as it could have been. I'll try again, if your pump is hooked up so a vacuum gauge is connected to the intake (suction) of the pump then you restrict ( cover the intake on the other side of the gauge, the gauge should register. Mine will show 25" if I do this.
If you use your finger to block the suction of a 1/4" tube, this will not feel like a great deal of suction ( no blood blister here). Hooking a 1/4" line to a vacuum chuck that is 4" in diameter translates into enough suction to collapse a thin walled turning. Hope this is helpful.

 

[Tom Albrecht]

Yep, yep that's what I thought. Thanks for the clarification.

 

[Bill Boehme]

Are you saying that the motor stalls on your vacuum pump when the input port is blocked? If so, I would wsay that the motor is defective. How much vacuum is the pump able to pull before stalling?

 

[nicktodd]

Are you saying that the motor stalls on your vacuum pump when the input port is blocked? If so, I would wsay that the motor is defective. How much vacuum is the pump able to pull before stalling?

If the motor stalls, I don't think he will see any vacuum at the gauge...

 

[Bill Boehme]

If the motor stalls, I don't think he will see any vacuum at the gauge...

Right, and that is why I asked the question. The OP said it came to a complete stop. I asked for clarification because to me it sounds like a motor problem. A stalled notor doesn't result in the same scenario as turning the motor off. In the first case, the rotor holds its position and vacuum would be held (probably slowly bleed off). In the second case, the motor would unwind and quickly dump vacuum.

 

[Tom Albrecht]

It's going back

Yes, the motor stalls. When I slowly block the intake with my finger, the guage slowly gets to 10" then drops off completely as the motor stalls.

So, it is likely the motor, but I'm getting a refund.

The cost for this is the $27 return shipping cost. Annoying, since I asked the seller if it worked before buying it.

That's enough for me and the Ebay used pumps. I'll buy a new one.

Disappointing since I did have a great one that I got from the Surplus Center years ago, but somebody swiped it during my recent shop relocation.

 

[Bill Boehme]

An experience like that certainly is not pleasant even with a refund. It is too bad that the seller isn't responsible for return shipping in a situation such as that.

I lost about $250 on eBay once when I didn't receive a VFD that I purchased. The seller says that it was sent and this was about a month before there was any sort of buyer protection policy on eBay years ago. I still buy things occasionally on eBay, but now I always thoroughly review the reputation of the seller first. Anything less than a 99.9% positive rating is not good enough. I also reject any seller who "weasel words" his sales.