Oil in the brake fluid reservoir

Agree with what you said 100 percent.

Personally, I’d change the master cylinder and flush the brake fluid and then see how it stops vs just replacing everything off the bat.

I am starting to think BS on this thread #1 OP said this was done 3 yr’s ago and I think we will all agree that in that time frame a seal or something would have been leaking or worse and the fluid would need to be topped off which OP said nothing about or if they did top it of did they use oil or brake fluid #2 OP said nothing when his father was called an idiot or jerk as most people would, :upside_down_face: :poop:

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You’re wrong.

The brake system is not a circulating system.

It’s a displacing system.

This means the fluid doesn’t flow thru the various components.

Instead the fluid is displaced by one component, (master cylinder) which then displaces other components, (calipers/cylinders)

So, if there’s going to be a problem with any of the seals in the system, the first component would be the master cylinder.

And from what OP describes, it sounds like the master cylinder is leaking internally.

Tester

It would not be the first time I was wrong.

true but after 3 years of driving you would think it would reach everywhere by now.

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While it’s a displacing system by design, when getting pushed back and forth the fluid doesn’t move uniformly with the result that some of the oil contaminated fluid that advances will hang up in the boundary layer and gradually advance farther down the lines with successive strokes. Something similar occurs when tides move up and down a coastal river or slough, the flows in both directions vary across the channel. Molecules of liquids also spread by both convective mixing and “pure” diffusion - put a drop of ink in very still water inside a thermos bottle (to reduce convective mixing) and it eventually becomes uniflrmily distributed because the molecules are always jumping around, exchanging places. Three years seems like sufficient time for the oil to migrate beyond the master cylinder.

I’m concerned that if elastomer seals in the antilock block aren’t replaced and fluid thoroughly flushed the oil that remains will simply spread around again.

So did it sit for years after the oil was added, or before? It sounds like the car just began being driven again.

I suspect he was pulling your leg. The car wouldn’t steer, regardless of speed, with even one broken tie rod. Sounds like one of Tom or Ray’s smart ass remarks before they give the real answer.

Agree. Also think about the displacement required by two pumps of the pedal. That can happen with air in the line as air is compressible. But no seal in the system can expand that far with out blowing and leaking fluid. The only possibility is one of the rubber hoses going to the caliper expanding like a balloon and contracting again. But one of those hoses would not reach a point where it stops expanding and holds firm so the brakes get applied. I see no way you could pump twice on the pedal and then get brakes applied without having air in the system.

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I saw them hanging down.

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You may have been looking at stabilizer links, a car can be drive without a stabilizer bar but not without steering.

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