Pump sputtering bad on start up (high speed)

[mjs31]

I have a pentair two speed pump that I usually run in low speed. Due to some urgency I am now running in high speed. The problem is starting up in high speed causes a bad sputtering noise and shaking. It stays at about 2 PSI and will never go to a normal run. If I start it up in low speed and then switch to high speed it is fine. Also, if I am running in high speed and then cut the power, but immediately turn it back on it is also fine and running at 12psi

May it be due to a leak somewhere in the system causing a loss of pressure?

[Poconos]

Can't really think of anything to help but can you tell if there is any air getting into the pump basket? Also, can you tell if the motor is up to speed when the shaking occurs? The shaking is strange.
Al

[Phillbo]

maybe it flung an impeller blade

[mjs31]

Can't really think of anything to help but can you tell if there is any air getting into the pump basket? Also, can you tell if the motor is up to speed when the shaking occurs? The shaking is strange.
Al

It is probably an air issue. If I start in low speed and then click to high speed it purrs...but most times when I start it in high speed it will sound like it is struggling badly. I do notice that several time when I then restarted it I get a huge amount of tiny bubbles out of the return line. Probably air. I guess starting in slow speed is a subtle way of priming it?

[brittmer]

I have a one-speed pump that when the pump was cold and I started it up, it would struggle to get going. Once it was running it kind of surged all of the time instead of running smooth. If I shut it off and then right back on it worked fine.
Mine ended up being a bad startup capacitor on the motor. Maybe the capacitor is bad allowing enough juice to start in low speed but not enough for high speed.
Check this post and it will tell you how to check the capacitor. http://www.poolforum.com/pf2/showthr...t=hayward+pump

[mjs31]

Thanks...you may be on to something. I tried again today and the same thing happened. I didn't have a 2x4 but my boot worked. I gave it a decent boot and it started up. Will have to clean the contacts when the weather clears. Thanks much for the post.

I have a one-speed pump that when the pump was cold and I started it up, it would struggle to get going. Once it was running it kind of surged all of the time instead of running smooth. If I shut it off and then right back on it worked fine.
Mine ended up being a bad startup capacitor on the motor. Maybe the capacitor is bad allowing enough juice to start in low speed but not enough for high speed.
Check this post and it will tell you how to check the capacitor. http://www.poolforum.com/pf2/showthr...t=hayward+pump