Large pipe thread problem

[Chris Kennedy]

I have a couple of rain barrels to help with watering the garden. They are old food barrels, and the openings on the top are about 2" in diameter, threaded. I use a siphon pump from the auto store to pull water out when I need it.

What I would like to do is rig it so that the pump can stay in the hole all the time. Unfortunately, it has a much smaller and finer thread, so it cannot be screwed in (which is probably to stop someone from hooking a fuel line to a food line, which makes a lot of sense). And it needs to be a tight seal, or we are going to breed mosquitoes. It also has to be removable to clean the barrel.

So, does anybody have any suggestions on how to match the food-grade thread? Here's the catch -- I don't have a lathe, otherwise I would experiment. Any threading taps I have seen are nowhere near big enough.

Thanks in advance,

Chris

[Jim Sears]

Maybe you can find a cheap thread guage and check it??

[Jim Becker]

...or you can put in a BT mosquito preventative ring to keep things simple. These are inexpensive and not harmful. They are commonly used for birdbaths and small ponds for that reason.

[Randy Cohen]

it seems to me that you should be able to find pvc fittings that can be adapted to your barrel openings. does the barrel have a removable lid?

[Jerry Bruette]

Chris,

Did the barrel have what's called a bung in the hole when you got it? If it did I might be able to help you out with a fitting that has a smaller pipe thread in the middle.

Jerry

[David G Baker]

If I remember correctly the bung threads are the same as one of the larger standard pipe threads. 2" or 2 1/2". You should be able to get an adapter fitting to fit your pump. You may have to use metal pipe fittings or go to a pipe supply business if you want plastic.

[Joe Tonich]

Add 1 or 2 drops of soap to the water in the barrel and you don't need to worry about mosquitoes. Won't hurt your garden any either.

[Ed Costello]

Hello.

Plug the hole you have with th appropriate threaded plug. Now buy a 2" "bulkhead" adapter or "tank" adapter. Go to the Spears pvc fitting site and you will see a picture of one. This fitting can only be installed if the top on the drum is removable.

Cheers,
Ed

[Chris Kennedy]

Everybody,

Thanks for all the advice and sorry for being away from this thread for a couple of days. Life has been hectic.

Also, please be patient with me. I know between Jack and squat about plumbing, and Jack just left. Seriously. Jim (Sears) recommended a thread gauge, and it hadn't occurred to me that such a thing exists. Of course, I looked at both the orange and blue borgs, HF, and my local hardware store. No luck.

So, the top of the barrel isn't removable. It has two bungs -- one has a tube plumbed into it, which goes to a diverter in the downspout. The other is just the straight bung, which threads in (this is what I want to modify). My first thought was same as Randy's -- I should be able to find a PVC-type fitting that should mesh with the thread. Now, I have only been looking at the blue and orange borgs. I'll look through the Spears PVC site and see if I can find something that will work.

As I am writing this, this seems to be a case of picture is worth a thousand words. I'll try to take a picture of it and post it.

Again, thanks for the help.

Cheers,

Chris

[Rollie Meyers]

Try a 2" PVC male adapter on the bung, they are cheap enough to try it out.

[Rich Engelhardt]

Hello,
I'd grind the threads off the bung hole, make a bracket to hold the pump and use a gasket of some kind to form a seal - maybe punch a hole in a rubber ball.
A rubber ball could be used to seal the bung hole when the pump was removed.

[Kyle Kraft]

Don't know if anyone mentioned this before, but often plastic drums will have a 2"NPT bung and another bung with a very coarse buttress thread. The NPT hole is easy to adapt, however the buttress thread is not. You would need another bung plug with buttress threads on the OD and (usually) 3/4" NPT female in the center.

[Peter Stahl]

Don't know if anyone mentioned this before, but often plastic drums will have a 2"NPT bung and another bung with a very coarse buttress thread. The NPT hole is easy to adapt, however the buttress thread is not. You would need another bung plug with buttress threads on the OD and (usually) 3/4" NPT female in the center.

The attached picture is what Kyle is talking about. The acid drum at work which are plastic come with these type of bung plugs. Also this is the link to that web page: http://www.bayteccontainers.com/bungcaps.html

[Jerry Bruette]

Chris,

I have access to both type of bungs that Kyle talks about, I'd be happy to mail them to you if you need either or both types.

Jerry

[Chris Kennedy]

You have to love this forum. The buttress thread is exactly what I am trying to match. From what Kyle is saying, my chances of finding appropriate fittings is next to nil. But I can modify a new bung cap to mate with the pump, I'm certain.

So, Jerry, if you think you can get a hold of a couple of bungs, I would definitely appreciate it.

Thanks for everyone's help. You have to love this forum -- there is just a huge amount of knowledge and experience.

Cheers,

Chris

The attached picture is what Kyle is talking about. The acid drum at work which are plastic come with these type of bung plugs. Also this is the link to that web page: http://www.bayteccontainers.com/bungcaps.html