closed loop noise?

[ste6168]

Hey everyone, i just got done setting up a calfo style manifold closed loop system on my 75. I have 5 outlets on the closed loop and am using a mag 12. I dont understand, but the pump is VERY loud, sounds like there is air stuck in the pipe somewhere because when i clog up the outlets except one it quiets down, but open them again and it is loud... anyone have any experience like this before? If so let me know how to fix it please.

Thnks, Mike

 

[integlikewhoa]

Sounds like the pump cavataing. Possible problems is not enough wtaer getting to the pump. Which could be caused by a small pipe. You usally have to run atleast one size bigger. how is it setup and what size pipeing?

 

[ste6168]

well it is late now but it is a mag 12 that is running over the top like melevs closed loop design... umm it has 1 inch piping that steps down right at the pump the goes to 1 inch outlet piping that as soon as it meets the manifold it steps down to 3/4" pipe. Do you think i should try a 1 1/4" intake or maybe 1 1/2" ?

Thanks, Mike

 

[DJ88©]

I'd place money on cavitating. By only running a 3/4" pipe you are restricting the intake of the pump. Especially when it has to draw up and over instead of directly into the pump I always go much larger. Two steps is my usuall norm. I'd go for 1 1/4" all the way into the pump.

hth

 

[integlikewhoa]

<a href=showthread.php?s=&postid=6607238#post6607238 target=_blank>Originally posted</a> by DJ88
By only running a 3/4" pipe you are restricting the intake of the pump.

I think you missed the part that says he ran 1inch. Well it would be nicer to be bigger then 1 inch. But going up to 1.25 im not so sure will solve all your problems. You might have to throttle back the the output. I a mag 9 on the outside of my water change drum. It makes the same nosie. And my pump is mounted into a buckhead right on the drum. No pluming going into it. Has one pip going up and then back into the drum. It freakin noisey. But its in the garage so i never botherd doing anythign about it.

I just told you this because as im thinking my pump is straight into the drum and i still have the problem. So upping the pipe a 1/4 inch is probley not going to fix your problem. It might be the pump has to have some head pressure on it to get rid of this problem. Do you have much plumming after the pump? Might be back to throttleing it back a bit. Putting some back pressure on it. Maybe someone else can help out a bit more.