Vacuum Powered Liquid Extractor!





Introduction: Vacuum Powered Liquid Extractor!

About: Update 12 September 2017: A very special thanks to Sam Elder, a manager here at Instructables, who tracked down the cause of my lost publications and fixed the issue. Take a bow Sam!

I always wanted an easier means to remove liquid when I'm doing car maintenance. By this I mean;
-removing power steering fluid.
-removing transmission oil.

-bleeding brakes.

Here is how I made this very convenient tool in less than half hour.

Step 1: The Liquid Air Separator.

This old water pump filter I decided to convert into my liquid air separator. The clear jar is perfect to let me see how much stuff I have removed. Also, it's pressure construction is important for the upcoming steps.

Step 2: Making an Output Connection Port.

I used a spare washing machine water hose to make an output connection. I cut a 2 inch length of hose. A 1/4inch nipple I threaded into the hose segment with the help of my spanner. I pushed it into the out port of the filter. The fit was nice and snug!

Step 3: The Input or Suction Connection.

Another hose segment I pushed into the IN Port of the filter. Using 3/8inch clear vinyl tubing, I pushed one end into the hose. The other end will be used to suck liquid.

Step 4: The Vacuum Source.

My trusty hvac vacuum pump will be used to generate the vacuum. Eventually I may have a dedicated 12volt vacuum pump to do the job but for now I will use the equipment I already have. I used a spare vacuum hose to couple the pump to the diy port on my liquid catch bottle.

Step 5: Testing!

I used a bucket of water to do a quick test. Turning my vacuum pump on, the end of the vinyl tube sucked greedily at my finger. Good!

Putting the tube into the bucket now, the water was sucked rapidly! The level shown in the pic was pulled in less than 10 seconds!

The top can easily be unscrewed for me to dump the liquid!

In reality the viscous liquids I intend to remove will take longer to extract but I'm anxious for field trials.

Step 6: Completion!

I'm pleased with the performance of my liquid catch bottle! To make it portable I put a carry strap secured via cable ties. I can't wait to bleed brakes now!



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    14 Discussions

    It works I have used simulare pumps for removing oil. More for anti-freeze and windshield washer fluids thu. some plastic pumps cannot handle petrol-chemical fluids that's why they have .Ceramic and Metallic pumps for corrosive and petrol-chemical fluids.

    I used this to extract water from a a broken line in the yard, with an electric drill and after 5 minutes it smoked it's soul. Better to spend the $ on something else or use it in a stop and go fashion. Thanx though.

    The water filter container does not provide the security from contaminating the vacuum pump. It allows the fluid to be drawn up into the pump which will damage it. a oil / water separator filter for a air compressor would help. By installing this in series with the capture tank with a quick disconnect air connector would work.

    so would a shop vac work if the connections could be altered to fit? lol I don't have a vacuum pump but need to replace the transmission fluid in our 4-runner and it has a sealed transmission so no dip stick and really don't want to invest in the hvac pump. I guess a shop vac would be considered a 1 stage pump if my thinking is right lol maybe

    5 replies

    Shop vacs Should Never be used on petrol-chemicals Oils, and gasoline, Kerosene, or Diesel Fuel. They will Explode.

    A standard vacuum cleaner is not good for liquid extraction. It pulls too low a vacuum and it is too noisy. Your best best is a low cost hand pump extractor. I had one but gave it away after creating my wonderful diy extractor.

    thanks for replying I knew I was off track with the shop vac idea but needed someone with better knowledge to tell me it wouldn't work. lol Wife says I'm too frugal to put it nicely so I'll invest in a 2 stage pump thanks again

    You may be able to rent the vacuum pump at a nearby auto parts store.

    Any 2 stage HVAC pump will work fine. Even a cheaper 1 stage will do the job. All depends on your budget.