Drainage problems

[Jol jol]

Hello, I am a new member and glad to be on board. I don't know anything about plumbing, but know how to a plunger. As a member I hope to some gain knowledge and advice.

My sink water drains into my washing machine. When I drain the washing machine it goes back into sink. This has been going on for two weeks. This is what I have already done to solve the issue:
Used a plunger.
Used baking soda and white vinegar.
Removed the U- bench from under the sink (there was no blockage)
Poured hot water down the sink drain.
Used a shop bought strong solution & poured down the sink (had toxic smell).
A few months ago the same thing happened and I used white vinegar and baking soda, which seemed to resolve the issue, but it did not work this time. I have not had any recent plumbing done and up until a few months there had never been any issues. I used the washing machine and had to remove the water as it came into the sink. I emptied 4 buckets full of water.
Can you please help?

 

[centralheatking]

So your domestic sink drains into your washing machine and you are
needing advice....go get a decent plumbing outfit , get a few quotes
relax choose the outfit you trust and get it fixed
centralheatking

 

[Stigster]

I know you say it's a new problem but how is the washing machine hose routed? They usually come into a kitchen unit under the sink at low level then should rise up to a high point, higher than the spigot on the trap you are connecting it to. Like in the picture on this webpage How to use a dishwasher if drain is clogged

Now, that may or may not be a contributing factor in your problem here but make sure that is set up right first. Ignore if your washing machine goes into its own separate vertical standpipe.

You likely have a blockage in the waste pipe somewhere so you really should try to "snake" the pipe runs with a tool like this to break through any blockage and then follow up with some hot water and/or drain cleaner. 10ft Handheld Flexible Snake Sewer Pipe Drain Hair Clog Plunger Cleaning Tool - Walmart.com

This is usually DIY able so give it a go before you call in a plumber if you are happy to have a go yourself. If not, then follow CHK's advice above and call in a plumber.

 

[rpm]

Jol jol, ignore chk, this is a forum of helpful advice. Try what stigster says and come back if you need to.

 

[Jol jol]

Stigster and rpm thank you. I am going to buy a snake sewer pipe because I think the problem is further in the pipe somewhere.

Thanks for your advice.

 

[ntipp]

It sounds like you to call out professional for this as they will know more than me. They will know exactly what the problem is, it's a strange one because I've never heard of an issue like this before. However, it's all on the same system so it makes sense!