My house is on concrete slab, built in 92. My washer is an OLD kenmore. On a large size cycle, I hear glugs from the kitchen sink as the washer drains. It hasn't overflowed the washer drain yet, but I can hear it rising up in it a little. It never backs up into the kitchen sink, and the kitchen sink is not slow to drain, even if I fill both sides and empty them simultaneously.

Today, since the weather was nice, I...

1. I used a 25' hand auger down the washer drain in the wall. the first time pulled back a small amount of lint, nothing major. I ran it down again and it came back clean.

2. I got on the roof and ran the auger down the vent stack for the kitchen sink. There is no vent for the washer.

3. I opened up the outside cleanout under the kitchen sink and stuck the garden hose in there on full blast. It does not back up.

4. Even though I thought step 3 told me the kitchen<->main line is clear, I went to home cheapot and rented a 50' power auger and used the small (1.5? 2"?) cutter to scrape the line from the kitchen sink cleanout. Then for kicks I went to the front of the house and ran it down the 2 cleanouts for house & street side.

But when I run a large load, it still starts to back up.

Other info. The bathrooms are on the far end of the house and I have no issues with them.

My best guess is that the washer line has a restriction or corner in it somewhere where lint & soap have built up. But my 25' snake either doesn't reach or just pokes a hole through it. It just has the coiled spring end, but nothing bigger will make the turn in the washer drain trap.

What's my next step? I was reading some of the enzymatic drain build-up remover bottles at HD. That might be an idea, since I don't have a blockage. Will they eat lint? I've read that some of the more caustic, lye based ones won't?

If I were to apply one of them, will they make it down through the water in the washer p-trap? Or do I need to shop vac or blow the drain line out?

Thanks in advance,
Brian
Ft. Worth, TX

 

Is the washing machine the last leg before the waste pipe goes outside? How far is the kitchen sink from the washing machine? Probably not relevant but what is the diameter of the washing machine drain pipe? Is it possible that a pipe strap could have broken off or something heavy is leaning against the waste pipe near the machine machine thereby changing the pitch of the waste pipe? If you fill the bathtub(which would simulate the amount of water in a large washing machine) can you still hear the burping in the kitchen sink?

You seem to have done just about everything I can think of.

 

Guess I should have mentioned the layout. The sewer line comes into the end of the house where the bathrooms are. The washer is on the very far wall on the complete other side of the house. The kitchen sink is about 15' from the washer connection in the utility room. So you have:

washer, kitchen, long span across the family room, main line from bathrooms out to street.

The drainpipe in the wall that the washer hose goes into is 2" inner diameter, best I can tell, definitely greater than 1.5".

I don't understand the question about something leaning against the waste pipe? The laundry drain and H/C faucets are in a recessed plastic enclosure in the wall, just at the top of the washing machine. The drain pipe is behind drywall, then goes down through the concrete slab and under the house to where it meets the main line and out to the sewer. I really can't see any of it, but the opening where the washing machine drain hose sits into.

I filled one of the bathtubs and let it drain and went into the kitchen. No glugs.

 

My mistake, you said you are on a slab . If it were my house, I would try to flood the pipe and put that really thick Drano in. Normally, I'm a purist and would only use the snake, but I must admit that I had a similar problem at a house recently and after a number of different augers and 45 min of snaking I gave up and for the first time bought some of that crap, and it actually worked.
Is it out of the range of possibilities that the pipe is cracked in between the Washer and the Kitchen ?

 

I really, really, really hope that is not the case, but I suppose it's possible. I did have a hot water line spring a leak under the slab a few years back. That was $1200 to have a hole cut in my floor. But the plumber that did the work said that it's most common in hot water lines because of the expansion/contraction. For a drain pipe, that shouldn't be the case and the house doesn't have any foundation issues.

I guess that thick stuff would be the best bet, as it should go through any water in the trap? I looked at a bottle of Sodium Hydroxide/Potassium Hydroxide stuff, but it said to bail any standing water out of the line.