SPRINKLER TALK FORUM - You Got Questions, We've Got Answers

Quoted from "ccummins"

In my backyard, I have a 3/4 inch pvc pipe coming vertically out of the ground. The original owner had placed a hose nozzel on top of the pipe which I never used, but I managed to knock this off after using a weed eater while doing my yard.

All I wanted to do was cap this pipe off but I'm having a lot of problems.

First, I turned off the sprinkler system and returned to the pipe but found it still had some pressure. I then turned off the main located where my sprinkler system is located and returned once more - still some pressure. Finally, I had to shut off the water main to the entire house which worked. I used fine sand paper to clean pipe. I used the typical purple primer with some pvc cement made for wet conditions (blue). I placed the cap on and let it set for 15 minutes and then turn the water back on. POP - off the cap went.

Using the above steps as before, I let the cement cure for 1 hour and then turned the main on without turning on the sprinker system. I then waited 24 hours and turned the sprinkler system on and it held. I then went on vacation and 1 1/2 days later the cap popped off while I wasn't at home flooding the entire yard until a neighbor shut it off.

I know I made a couple of errors in doing this...1) I sanded the area of the pipe which someone told me not to do since they need to be tight fitting. 2) I put the cap on without having twisted it as per the directions.

So I went to Home Depot and got Christy's Red Hot glue and put a new cap on. It's been 24 hours and I'm so worried that I'm going about this the wrong way. I did notice that originally the pipe had what looked to be like gray cement used. Are there any high pressure cements out that are gray in color? Am I going about this the wrong way? What am I doing wrong?

Any tips would be greatly appreciated!!!!!




is the pipe threaded? can you post pics?

Quoted from "HooKooDooKu"

-- IF -- you really have a 3/4" WHITE PVC Sch40 or Class 200 pipe & a 3/4" PCV Sch40 glue cap, then to ensure capping it off doesn't blow...

Use PVC cutters to make a clean cut at the end of the pipe (you might have to do some digging to expose enough pipe). Clean the pipe with a rag and water (i.e. wipe of excessive dirt). Then finish cleaning it with the purple primer AND use the purple primer on the inside of the cap. At this point, the only thing that should be on the pipe and in the cap is the primer. After the primer dries, apply a coat of pvc glue (the blue stuff you were using initially should be fine) to both the pipe and the inside of the cap. The push the pieces together making sure to twist at least 1/4 of a turn. HOLD THE PIECES IN PLACE for about 30 seconds. Let it stand unpressurized for 2 hours.

If after all that it blows, then you are doing something fundimentally wrong... something like using a threaded cap, the pipe or the cap isn't Sch40 PVC or Class 200, you're barely putting any glue, or something else off the wall that is just wrong. Because following these instructions will result in a joint between the pipe and cap that is stronger than the pipe and there is no way you are going to blow the cap off.