Change your brake line

[Water Warrior 2]

No injury thank goodness. Luckily the pump was on the other side of a concrete divider wall when I closed the valve. No shrapnal hit me but a lot of water soaked me completely as it sprayed around.
Water hammers can cost a lot of grief sometimes. One of my co-workers did a no-no one night and fired up to really big pumps in the water distribution system. Talk about a pressure spike. He launched 38 fire hydrants into the sky. Main line breaks and a very annoyed repair crew. Last time I heard he was selling real estate.

[Gz Rider]

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[Water Warrior 2]

Boating !!! H*ll no. I have no talent that will keep me alive when the water is deeper than a bathtub. I have a fear of water after almost drowning as a kid. Can't swim and sink when trying to float in a pool. My last 25 years working as a water treatment operator was sometimes a little unnerving with open water so close and deep. Standing on a steel catwalk above 22 feet of water makes one thankful for safety railings.

[Gz Rider]

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[mrlmd1]

The brake line can fail by the rubber decomposing slowly over the years and the line gets clogged with debris, that's how it can act like a check valve - it may get pressurized by the brake lever or pedal and then not release because the line is partly clogged, and the brake drags.
If one line expands when the pressure is applied (and basically absorbs the pressure) and the other line doesn't (lets the pressure transfer to the brake cylinder) then the brakes will be applied unevenly and the car will swerve to one side. That is not acting like a check valve.

The reason for having steel braided cable wrapped brake lines is to prevent the expansion of the rubber line and more linearly transmit the brake pressure to the wheel cylinder. Brake lines do not fail very often, it's a rare thing, but changing them out every 5-10 years or so or when they look diseased is not a bad thing.

[alantf]

I remember, many years ago, that car brake lines used to be made of steel. This meannt that every couple of years they would rust through, & had to be changed. Thank goodness for copper or stainless brake pipes.

[mrlmd1]

The lines are steel except for where they have to flex, then there are rubber hoses where needed. Some of these may be covered in braid, depending on the manufacturer.

[jonathan180iq]

And braided lines = awesome brake feel
If you're going to do this, go ahead and upgrade!

http://www.galferusa.com/html/

[Gz Rider]

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[jonathan180iq]

A dragging brake can cause a car to pull over a long stretch, but to have a yank on the wheel like that, or a constant vibration through the steering wheel, sounds more like a funky rotor than anything else.

Obviously, if changing lines and what not has solved your problem, then you've done something right. Although I don't really know what it could have been, given the description of the steering wheel jerk.