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Frick
06-13-2008, 08:29 PM
I just swapped out my old brass heads for Hunter sprays with MP3000 heads. While the literature states 30 feet at 35psi, I realized that I probably wouldn't get that in real life conditions. What I wasn't expecting was only getting 15-16 feet radial distance. The heads are installed in a fenced in yard with a lot of trees in the neighborhood, so wind isn't a factor.

Has anyone else had similar problems?

I just realized as I was typing this the MPs have an adjustment screw on them. But don't they come set all the way open?

Keen
06-13-2008, 09:11 PM
did you check your PSI?

londonrain
06-13-2008, 09:12 PM
need more info on your system....psi, gpm available, number of heads on the zone, type and size of the control valve and the age of the control valve.

Frick
06-13-2008, 09:31 PM
I'll get a PSI measurement as soon as I can, the system has a booster pump. There are 8 heads in the zone, the control valve is probably 30+ years old. The lines are 3/4"

The MPs are in the back yard, the front yard has 5 pgps in the front, so I don't think gpm is a problem. What does concern me is the tree roots. When I turned the system on, I had very little pressure at any of the heads. After about 5 minutes I discovered a water bubble popping up. A tree root had pushed the line up and pulled a fitting apart. There had been a prior fix, but it went over the root and subsequent growth caused it to break again. I took some pictures, but I can't find the camera at the moment. I rerouted the line under the root, instead of over, and moved the T which had been sitting right on top of the root a couple of feet back.

My fear is a root has damaged a line badly enough to hamper the flow, but not enough to cause it to break. Is that possible, the majority of the supply line is gray plastic, most of the system is 30+ years old.

londonrain
06-13-2008, 09:45 PM
I'll get a PSI measurement as soon as I can, the system has a booster pump. There are 8 heads in the zone, the control valve is probably 30+ years old. The lines are 3/4"

The MPs are in the back yard, the front yard has 5 pgps in the front, so I don't think gpm is a problem. What does concern me is the tree roots. When I turned the system on, I had very little pressure at any of the heads. After about 5 minutes I discovered a water bubble popping up. A tree root had pushed the line up and pulled a fitting apart. There had been a prior fix, but it went over the root and subsequent growth caused it to break again. I took some pictures, but I can't find the camera at the moment. I rerouted the line under the root, instead of over, and moved the T which had been sitting right on top of the root a couple of feet back.

My fear is a root has damaged a line badly enough to hamper the flow, but not enough to cause it to break. Is that possible, the majority of the supply line is gray plastic, most of the system is 30+ years old.

If your valve is 30 years old then the diaphragm could be worn out and no longer has the ability to flex thus it can no longer get full flow....

Kiril
06-14-2008, 01:04 AM
A pressure test at the nozzles would be some good diagnostic information to have if trying to determine if roots are pinching a line.

bobw
06-14-2008, 09:36 AM
8 Mp3000's on a 3/4" line is not going to be very successful. Assuming they are at 180 (default setting for 90-270s, the most common), at 35 lbs, you're using 1.7 gpm per nozzle. 8 x1.7 = 13.6 gpm, much more than a 3/4 line will supply.

Cap off a few heads and adjust your corner heads to 1/4 circle, etc and then try again with all 8. If you have already made the adjustments, and are still having problems, you may want to look at swapping a few 3000s for 2000s which use less than 1/2 the water per nozzle (of course, less coverage as well...)

Mike Leary
06-14-2008, 11:35 AM
What they said.....MPs work best around 45 psi, just like their big brother,
the Toro Stream Rotor.

Kiril
06-14-2008, 11:39 AM
MPs work best around 45 psi

Unless your trying to get maximum radius reduction.

Mike Leary
06-14-2008, 01:11 PM
Unless your trying to get maximum radius reduction.

How true, why fool around with that silly flow control?

Frick
06-14-2008, 08:35 PM
Well I think I fixed one of the problems, I'm not getting 30' from the 3000s, but I'm probably getting 27-28, which is fine.

I connected the gauge and when I turned on the system I was getting less than 15psi at one of the heads. That seemed really, really low. There is a booster pump on the system and my father and I have been debating which way one of the shut valves should be turned. We both thought it should be closed when the system was running, but the irrigation company that turned the system on last year had said it was in the correct position when it was open. So I closed the valve and rechecked the pressure, suddenly I'm getting 37psi at the head and they seem to be working correctly.

Thanks for the help. And the main supply line isn't 3/4" just at the heads. The main line from the pump is 2" (I think)