need tool suggestion...clearing drain pipe obstruction

Reply

  #1  
Old 09-02-14, 05:13 PM
J
Member
Thread Starter
Join Date: Aug 2001
Location: Los Angeles County, California
Posts: 271
Received 0 Votes on 0 Posts
need tool suggestion...clearing drain pipe obstruction

About 12-18" into the septic tank inlet pipe there is a big obstruction. I can poke a thin piece of rebar through it in one place, but haven't been able to do more than that. I'm trying to think of a tool (like a short digging bar) that I could poke into the inlet pipe and chisel or cut out this obstruction. I don't have a drain snake and renting one involves some expense and a long drive and no guarantee that it'll work. This is a low budget, DIY operation.

The usual tee pipe at the inlet into the septic tank is broken, so I can poke straight into the inlet pipe...I'm thinking that with a long enough chisel type tool I might be able to chisel away part or all of this obstruction. It might be a root since there are some large oak trees close by.

A six foot digging bar might not fit into the septic tank...I think something around 3 feet would be right. I'm even thinking about a long drill bit with some kind of wide cutting end...is there such a thing? Maybe a short piece of 2" pipe that I could pound on from one end?

Any ideas about this?
 
Sponsored Links
  #2  
Old 09-03-14, 04:23 AM
V
Member
Join Date: Jan 2010
Location: North East Kingdom of Vermont
Posts: 2,533
Received 1 Vote on 1 Post
Is it PVC ?

Maybe you just have to saw it off prior to the blockage, clean it out while it's above grade, or replace it. Most concrete septic tanks have a built in neoprene gasket that the PVC slips out of.
 
  #3  
Old 09-03-14, 05:35 PM
J
Member
Thread Starter
Join Date: Aug 2001
Location: Los Angeles County, California
Posts: 271
Received 0 Votes on 0 Posts
This is a very old concrete septic system with cast iron pipe. I would sure be nice if the pipe would slip out from the tank, but it looks to me like it's cemented in place. But it is a nice idea, to replace the plugged up pipe with PVC if I could figure out how to detach the cast iron pipe where it enters the septic tank. Right now I'm also trying to dig out under the pipe where it enters into the tank, but there are many thick roots from a large oak tree...so it's slow going. It would be much easier and quicker to unplug the pipe.
 
  #4  
Old 09-03-14, 06:19 PM
B
Member
Join Date: Oct 2008
Location: New England
Posts: 10,512
Received 37 Votes on 34 Posts
Not a pro on this, but immediately inside the septic tank may be a baffle. From your description I'm not sure if you are dealing with a clogged pipe or just running into the concrete baffle.
Sorry if I'm lost.
Bud
 
  #5  
Old 09-04-14, 02:45 AM
J
Member
Thread Starter
Join Date: Aug 2001
Location: Los Angeles County, California
Posts: 271
Received 0 Votes on 0 Posts
There's no baffle and since the usual T fitting is partially broken, I could take a mirror and look(from inside the septic tank) up inside the pipe and see some kind of obstruction. Just past the obstruction, there's a hole in the top of the cast iron drain pipe (I had it patched and clamped previous to this) where I can see that there's a backup of liquid.

So I can access the obstruction from either side and I just have to find the right tool to knock it out with...the limitation being that this hole isn't that large (2x3") and it's awkward poking up the pipe from inside the septic tank.
 
  #6  
Old 09-04-14, 04:59 AM
B
Member
Join Date: Oct 2008
Location: New England
Posts: 10,512
Received 37 Votes on 34 Posts
A cut-off tool is basically a small (drill size) jack hammer. I have used them to chip away at concrete floors where only a small opening was needed. Fabricating something to reach into where you need to work might come from a rental shop, they often have a lot of solutions to strange problems.

Bud
 
  #7  
Old 09-04-14, 06:50 AM
V
Member
Join Date: Jan 2010
Location: North East Kingdom of Vermont
Posts: 2,533
Received 1 Vote on 1 Post
You can google roto-rooter and get some ideas regarding the tools they use, and maybe fabricate some of your own.

I've used my fibreglas chimney cleaning rods (multiple 4' sections) for straight sewage lines; even smaller chimney brushes.

Have any rigid ⅜ or ½ inch aircraft cable that you can cut into short 6' sections and stick in the end of an electric drill ?

I just finished working with my own septic inlet pipe which was comprised of a mishmash of Clay, PVC, and Orangeburg. A 5' diameter White Pine was sending invader roots out to attack the Orangeburg and the old Oakum in the Clay Pipe Joints. I don't think anything roto-rooter could send down would have done the job . . . . the Orangeburg (stiffened tarpaper) would have deteriorated before the roots gave up the ghost, and I dug it all up, and replaced the Orangeburg with PVC, and repacked the Clay with new Oakum and Hydraulic Cement.

For what purpose was the little hole previously put in your iron pipe ?

I suppose you need a tool that can make a 90° turn, if you use that hole for an entrance ?
 
  #8  
Old 09-04-14, 07:34 AM
P
Group Moderator
Join Date: Mar 2003
Location: NC, USA
Posts: 23,418
Received 590 Votes on 544 Posts
It sounds like digging up the pipe and replacing the section with a hole would be a good idea. I you can't poke the obstruction clear with a piece of rebar the pipe may have collapsed. You can cut out the damaged section and replace it with PVC and no hub couplings.
 
  #9  
Old 09-04-14, 06:35 PM
J
Member
Thread Starter
Join Date: Aug 2001
Location: Los Angeles County, California
Posts: 271
Received 0 Votes on 0 Posts
I've just been looking into the inlet pipe from inside the septic tank. About 8-10 inches from the point where the pipe starts(the actual inlet point) there is what looks like a horizontal half moon concrete obstruction, about 2-3 inches thick, and 1-2 inches high at the center of the moon shaped curve/saddle. Then there is what looks like empty space for about 12", then some kind of obstruction taking up the entire diameter. I can poke thin rebar (3/8") through this 2nd obstruction easily, and if I waggle the rebar back and forth I can get some liquid to drain through but it stops when I stop the waggling.

The first half moon obstruction makes it hard to get anything through to the 2nd obstruction but I have some 1" pipe I'm going to try since the thin rebar doesn't do anything much.

Anyone know what this half moon piece of concrete could be. It's a perfect half moon so it has to be man made...but what purpose could it possibly have? It's counter productive to the idea of a drain pipe. Maybe it's the junction between the ceramic pipe at the inlet and the cast iron pipe, but I'm puzzled by it since it would block solids from draining into the tank. There's about a 2" open space in the pipe above the half moon saddle.
 
  #10  
Old 09-05-14, 01:06 AM
B
Member
Join Date: Oct 2008
Location: New England
Posts: 10,512
Received 37 Votes on 34 Posts
I'm still thinking there is a baffle in there as the flow into a septic is often directed downward just inside the tank and it sounds like you are punching a hole through that baffle. But it is 4am so I might just be sleep walking. Anyway, here is a diagram:
http://www.jgallagherseptic.com/how-...stem-works.asp

Bud
 
  #11  
Old 09-05-14, 09:36 AM
Z
Member
Join Date: Jan 2008
Location: Southeastern Pennsylvania
Posts: 3,133
Received 13 Votes on 13 Posts
Hi guys –

Well I know you guys know a lot more than me about this, but I was wondering if that cast-iron drain pipe was cradled by some type of concrete support. Then the pipe actually broke and fell down an inch or two. So now when you look into the end of the pipe you see what looks to be a half-moon in the pipe?

Just a thought, but I don’t know how likely it would be for the cast-iron pipe to actually break in two.
 
  #12  
Old 09-07-14, 03:20 AM
J
Member
Thread Starter
Join Date: Aug 2001
Location: Los Angeles County, California
Posts: 271
Received 0 Votes on 0 Posts
I've dug out the cast iron drain pipe all the way to the septic tank (at the tank just the top part so far). And I see two things. The ceramic pipe (which has the tee/baffle that broke off) extends through the cement tank wall to it's edge. The cast iron pipe extends just to the ceramic pipe, but not into it...and the cast iron pipe has dropped almost two inches leaving a nice gap that's partially filled by a root. I haven't dug under the cast iron pipe right there, so I don't know how or why it dropped. There was an earthquake 15 years ago that could have done it, but the septic system has been working fine until the last year.

I'll know more when I finish digging under the pipe, but it's slow hand work (using some small hand tools...there are some 1-2" roots crossing above the pipe making access difficult).

Because there is a ceramic pipe going through the wall (actually the corner) of the septic tank, I'm not sure if I can run a new 4" pvc/abs drain pipe into the septic tank through the ceramic pipe. And I'd probably have to chip/break the 8-10" long ceramic pipe (probably imbedded in cement) to get it out, not an easy task. But that's probably the best solution as I could then put in a new tee/baffle, and also add a clean out somewhere on the new plastic pipe.

The alternative is to try to raise the cast iron pipe two inches. This section of pipe is 6-8' long and ends in a 90 deg cast iron elbow. Something will probably give if I try to raise this pipe so that it matches up to the ceramic pipe.

I'll be working on it in the next few days and should know more once I dig under the end of the cast iron pipe. But I'm open to any more suggestions, especially on removing the ceramic pipe if I can't fit a 4" plastic pipe through it.
 
  #13  
Old 09-07-14, 05:30 AM
P
Group Moderator
Join Date: Mar 2003
Location: NC, USA
Posts: 23,418
Received 590 Votes on 544 Posts
Unfortunately it is common for the drain pipe to settle like you have. During installation they probably over dug and left a void or filled in a place they over dug and did not compact the dirt so the pipe was not properly supported. Add to that ground settling over the years and people driving over the area and things move.

Don't bother digging below the pipe. Just get down to the bottom of it and remove the old pipe. Fill in and compact any low spots to provide continuous support for the new pipe. Don't worry about saving the old pipe penetrating the tank. Knock it out and shove in your new PVC and seal around it with hydraulic cement or mortar.

The best place for a cleanout is usually just after the drain pipe exits the house. They make special cleanout fittings sorta like a T but with a big sweeping arc in both directions so you can snake up into the house and out toward the septic tank from one location.

 
  #14  
Old 09-08-14, 03:04 AM
J
Member
Thread Starter
Join Date: Aug 2001
Location: Los Angeles County, California
Posts: 271
Received 0 Votes on 0 Posts
The problem will be how to remove the ceramic pipe...I don't think it will just pop out. It's about 8 inches long and the walls are about 3/4" thick and it might have been laid in fresh cement when the tank was built.

I already have a clean out next to the house, it has a large 4" threaded opening (black ABS pipe) and works welll. I thought I'd put in another out about 3 feet from the tank, it'll be buried but might come in useful someday.
 
  #15  
Old 09-08-14, 04:01 AM
V
Member
Join Date: Jan 2010
Location: North East Kingdom of Vermont
Posts: 2,533
Received 1 Vote on 1 Post
I've been dealing with my own septic issues this summer, and learned a little about clay pipes. I think you'll find that the standard was 4 feet in length (still pretty heavy), and the joints were packed with Oakum (sometimes sealed with molten lead, sometimes not). They should come apart easily. There are pipe scoring devices around so you can break them off smoothly, and "FernCo" makes all kinds of rubber couplings to allow you to link up any Clay pipe you choose to retain with the remaining Cast Iron, new PVC "thin wall drain tile" or either 3" or 4" Schedule 40 PVC.

FernCo's almost endless number of choices of "fittings" is confusing, but still a bit comforting, in making you realize that other people have encountered these same problems before, so you're not the first one.

I also learned that sprinkling some granulated Copper Sulphate around these precious pipes will discourage the tree roots from immediately trying to re-invade your joints.
 

Last edited by Vermont; 09-08-14 at 04:41 AM.
  #16  
Old 09-08-14, 07:38 AM
P
Group Moderator
Join Date: Mar 2003
Location: NC, USA
Posts: 23,418
Received 590 Votes on 544 Posts
The pipe through the wall of the tank is most likely cemented in place just like you'll do with the replacement. It will come out with a hammer and chisel and by busting the pipe but a rotary hammer set to hammer mode and a chisel bit makes it go much easier.
 
Reply
Posting Rules
You may not post new threads
You may not post replies
You may not post attachments
You may not edit your posts

BB code is On
Smilies are On
[IMG] code is On
HTML code is Off
Trackbacks are Off
Pingbacks are Off
Refbacks are Off


Thread Tools
Search this Thread
 
Ask a Question
Question Title:
Description:
Your question will be posted in: