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coxlandscaping
11-12-2007, 06:20 PM
Is anybody having trouble with Hunter I20 popping up had a customer call me today about 4 of there heads not wanting to popup I went by and you can pull up on them not very hard and they will come right up and run fine I noticed that you could push down on them when they are running and you can feel it like click into place and they will not pop up pull on it a little and it will take right off should I just replace all 4 and see what it doe’s it has been working fine all summer according to the customer it worked fine when we put it in

YardPro
11-12-2007, 06:26 PM
i-20's require a higher working pressure... about 300 psi minimum.

I have had a few stick down. I unscrewed the body and cleaned it out and it was fine. I think the center turret was in a bind when the cap was screwed on.

irritation
11-12-2007, 06:29 PM
Sounds like the pressure is too low for I-20's. Pull the rubber off the check valves and they should pop up fine.

zman9119
11-12-2007, 06:49 PM
i-20's require a higher working pressure... about 300 psi minimum.
Holy cr:dizzy: p

londonrain
11-12-2007, 07:59 PM
The I-20 has a much stronger spring than the PGP.... if the head will not pop up then it is a pressure issue....

hoskm01
11-12-2007, 08:04 PM
Had same problem with some Toro's pressure fix cured it i think 300 psi might be a bit much might break something try more like 50 look just to the left of the enter button there a few keys we call them punctuation try them next time you post cause if you dont your sentence seems to go on and on even though youve really written a paragraph people think youve written a sentence cause theres no punctuation:dizzy:

FIMCO-MEISTER
11-13-2007, 06:17 AM
Had same problem with some Toro's pressure fix cured it i think 300 psi might be a bit much might break something try more like 50 look just to the left of the enter button there a few keys we call them punctuation try them next time you post cause if you dont your sentence seems to go on and on even though youve really written a paragraph people think youve written a sentence cause theres no punctuation:dizzy:

You are meant to read it like a poem.

YardPro
11-13-2007, 06:22 AM
LOL

i meant 30psi...sorry

FIMCO-MEISTER
11-13-2007, 07:47 AM
Yank the I-20 and install maxi-paws.:)

Kiril
11-13-2007, 07:53 AM
Yank the I-20 and install maxi-paws.:)

:laugh: Do ya one better, yake the I-20's, install plugs/caps.

coxlandscaping
11-13-2007, 08:36 AM
I’m not sure I understand why it would be a pressure issue when we have 10 I20s that are running fine on a different zone which are up hill from these and the 4 I am talking about are on a zone with 9 I20s just curious

Wet_Boots
11-13-2007, 08:50 AM
Use the flow control to turn off a head or two of the four, and see what happens. You may have a blockage at a fitting. Or a pipe choked by a tree root.

FIMCO-MEISTER
11-13-2007, 09:58 AM
choke:
to grip (a bat, club, racket, or stick) at some distance from the end of the handle.

foss
11-13-2007, 11:45 AM
I'm assuming you've already tried pulling out all the risers and flushing the line again.

irritation
11-13-2007, 02:59 PM
I've seen this before and removing the check valve has always worked. It's usually on heads that don't need a check valve anyways.

coxlandscaping
11-13-2007, 09:45 PM
I will try removing the check valve that will be the easiest thing to try first I think thanks for all the advice and help I will let you know if this works thanks again

BrandonV
11-15-2007, 03:13 PM
LOL

i meant 30psi...sorry

glad you corrected that... I use i-20s exclusively and was about to call you out. :drinkup:

Mike Leary
11-15-2007, 04:33 PM
I also have hundreds of I-20s in service( 6" stainless ultras ) & have NEVER had the "problem" you all speak of. 30 psi is zip city for those big guys,
I'd be thinking hydraulic problems elsewhere, granted the low drain checks
could have fouled...but that would have to be some mass skanky water. Are
you on a well or community service where the psi has changed? Check the
flow control on the valve..open up the bonnet, check for skank.

mangusta1969
08-12-2008, 03:04 PM
Recently I changed out a number of Hunter PGP rotors with some Hunter stainless steel I-20 rotors. In my recent testing of different rotors and nozzles at a couple of rotor locations in my system, the I-20s had a longer throw distance than the PGPs or any of the rainbird rotors that I tried.

In switching some of the rotors from PGP to I-20 SS units, I was trying to correct somewhat for a bad installation design from 13 years ago (too much distance between some heads and not enough heads in some places on a 9 zone, 40-45 rotor system).

Unfortunately, 2 of the 6 brand new I-20 rotors that I installed in various zones had pop-up problems. One I-20 would never pop up by itself and the other I-20 only popped-up intermittently. I suspected some minor flow or pressure problems in these two locations, even though I had a good throw radius of 32-34 feet, using a 6 gpm nozzle in both of these I-20s.

I solved the never pop up problem location by swapping in a different I-20 rotor, but I could never get the intermittent pop up location to work consistently with an I-20 rotor. This troubled location worked fine with Hunter PGP rotors/6 or 8 gpm nozzles, but the PGP rotor would only throw water to a radius of 24-25 feet and I still needed the longer throw distance of the I-20.

I finally decided to customize one of the I-20 rotors by taking it apart and cutting off 1 and 1/2 coils of the retract spring to reduce its retract tension. The modified retract spring tension is less than an unmodified I-20, but it is still significantly more that the PGP's retract tension. The modified I-20 is now working just fine to pop up and fully retract the stainless steel rotor body.

I didn't want to try removing the check valve, as some have suggested, as the troublesome zone is located on a sloped area.

I hope this tip helps someone with I-20 pop-up problems. With their excessive retract spring tension, I doubt anyone is having I-20 rotor retraction problems.

Mike Leary
08-12-2008, 04:39 PM
Any head you can push down easily has a pressure problem, not just I-20s.

AI Inc
08-12-2008, 04:43 PM
Any head you can push down easily has a pressure problem, not just I-20s.

Very true, but if he thinks he is going to run I -20,s on 30 lbs , he dosnt need an irrigation guy, he needs a magician.

WalkGood
08-12-2008, 04:59 PM
. With their excessive retract spring tension, I doubt anyone is having I-20 rotor retraction problems.

The "excessive retract spring" is strong, I believe, to help with higher elevation differences of low head drainage issues.

If any head in one spot just won't pop up on it's own, then there simply is not enough flow &/or pressure at that spot to raise the dead. If the other heads on that zone are fine then suspect a blockage of some sort. Rock in an elbow or other inline fitting/reduction of diameter.

WalkGood
08-12-2008, 05:02 PM
Very true, but if he thinks he is going to run I -20,s on 30 lbs , he dosnt need an irrigation guy, he needs a magician.


Some Viagra for underperforming pop-up.

:rolleyes:

Wet_Boots
08-12-2008, 05:06 PM
Why use 6 or 8 gpm nozzles for only throwing 32-34 feet? If re-nozzling an entire zone doesn't bring up the pressure, you might be looking at using Maxipaws.

mangusta1969
08-12-2008, 05:42 PM
Wet Boots,

Good question on using the higher gpm nozzles on some of the rotors in my system.

I live near Reno, Nevada, where the summer sun can quickly cook a full sun turf area if it is not getting enough water every other day. I suspect the original installation in 1995/1995 probably used pop-up impact sprinklers (maybe maxipaws, if they were available back then), but certain areas of the turf were not getting enough water from the PGP rotors when they replaced the impact sprinklers with rotors.

I have attempted to get adequate precipitation rates on the sunny areas during our restricted watering hours (only about 6 hours of total yard watering time every two days across 9 rotor zones and 2 drip zones) and balance the system by putting in some high flow nozzles on the sunny areas and using lower flow nozzles on semi-shady and shady areas. I would be in a lot better shape if the original irrigation system designer had zoned the 1/3 acre turf area according to sunny and shady areas and had used some uniform head spacing in his design. Instead, he left me with some 5 rotor zones in which 3 of the rotors may have full sun all day and 2 rotors in this zone have shade most of the day. The original designer also skimped on the number of sprinkler heads and zones to cover the turf area.

I don't have a pressure gauge to assess any pressure issues (like I should have), but from looking at the stated nozzle sizes vs psi and the observed throw distances that I have for the I-20 nozzles and the PGP red and blue nozzles, I would say that my operating zone pressures are marginal, at 35 psi or so. Thus, the pop-up problems occurred with some of my I-20s. None of the PGP rotors have ever had any popup problems.

Since the PGP rotor body diameter and lengths are about the same as the dimensions for the I-20 rotor body, I don't understand why there is such a big difference in the strength of the retraction springs between the two rotor models. None of my PGPs have any rotor retraction problems, so why such a big change (tension increase) for the I-20 springs?

Wet_Boots
08-12-2008, 06:09 PM
I-20 heads have a much stronger spring, to serve the head's ability to prevent low-head drainage.

Mike Leary
08-12-2008, 06:53 PM
I-20 heads have a much stronger spring, to serve the head's ability to prevent low-head drainage.

As the I-40 and on up...the problem is the friction loss in the low drain-check
valve; you lose 7 psi with the I-20 check, on a marginal psi system, this is
the straw that breaks the system's back.

mangusta1969
08-14-2008, 01:14 PM
All,

Thanks for the check valve insight that contributes to why the I20 rotors can have problems with popping up on a marginal pressure system, even though other rotor models were working okay in that system. My I20 with a cut down retraction spring (I removed 1.5 coils from the coil spring) is now popping up reliably just fine in my troubled zone.

The modified I20 is throwing water about 10 feet more than the Hunter PGP rotors in that same zone and 10 feet more than the PGP rotor that it replaced. That's just what I needed to compensate for a less than stellar system design and layout.

CAPT Stream Rotar
08-14-2008, 05:28 PM
how did you remove the spring?

Mike Leary
08-14-2008, 07:42 PM
All, My I20 with a cut down retraction spring (I removed 1.5 coils from the coil spring) is now popping up reliably just fine in my troubled zone

"Fools rush in where wise men fear to tread". (And, yet, it worked)

mangusta1969
08-14-2008, 08:06 PM
CAPT,

To gain access to the I-20's lower spring coils so that you can cut through a coil about 1-2 turns from the bottom of the spring, do the following:

a. Unscrew the top black plastic cap of the I-20 sprinkler body
b. Remove the lower (outside) body of the I-20, giving you access to the large coil retract spring and the rotor mechanism
c. While holding the rotor mechanism upside down on a workbench, compress the retract spring downward about 1 inch, while simultaneously using a small flat-bladed screwdriver to pry the top coil of the spring away from the segmented wheel/cylindrical body and move the free end of the coil spring upward over the segmented wheel.
d. Using the small screwdriver blade, unwind about two coils of the spring and move them upward over the segmented wheel. It may help to "unwind" the spring a bit (counter-clockwise movement) so that the coils move away from the inner cylindrical body of the I-20.
e. Use vice grip pliers to hold the coil spring area securely while you hacksaw through the spring at the desired location.
f. Using the vice grips, move the cut end of the spring downward over the segmented wheel. You may need to bend the spring a bit in case it is no longer tight against the plastic rotor cylinder. The outside body of the I-20 should should slide easily over the spring assembly.
g. Screw the top/rotor assembly back onto the lower body of the I-20

I cut 1.5 coils from a brand new I-20 to solve a "no pop-up/intermittent pop-up" problem. The slightly shorter spring still has plenty of tension to retract the rotor assembly when the watering period is over. The whole procedure only takes about 4 minutes. Be sure to use a sharp hacksaw blade, as the spring itself is made of tempered stainless steel.

Mike Leary
08-14-2008, 08:11 PM
:::Applies choke hold to self::::