Brake Gurus required

[infotechplus]

OK. I have been reading up on brake systems, proportioning valves and the like, and I have a question perhaps one of the brake gurus out there might be able to answer.

Here is the Brake Booster Vacuum Valve (for want of a correct term) I have:



As you can see it is marked with an "E" and an arrow. Now, it's a one-way valve. I know that because when I blow air through the end with the arrow facing away from me the air goes straight through. At the other end, it is blocked.

The Brake Booster (MA70) uses the engine to assist it by gathering air when the engine is running to maintain pressure when idling or even stopped (up to three presses of the pedal according to some websites).

Now, my questions are:

1. Is it essential to run this valve in the line between the engine and the booster? I would think yes.

2. Does the arrow and the "E" mean the valve is pointed toward the (E)ngine?

Here are two really good articles from the PBR website about braking systems, and bleeding brakes correctly. I hope you find them useful.

Braking Systems - 28 pages, pdf file, 2.08Mb

Guidelines for Bleeding Brakes in Front Wheel Drive cars correctly - 3 pages, pdf file, 63Kb

Thanks,

Peter

[CrUZida]

Some boosters have these built in, check to see if yours does.

Otherwise put it in the direction that prevents boost from entering the booster.

[oldcorollas]

E is for engine.
you ONLY WANT air to flow FROM the booster TO the engine (don't even think about vacuum).

you want to PREVENT air flowing FROM the engine TO the brake booster

essential as otherwise, the vacuum level of th ebooster will be the instantaneous vacuum level (or boost level) of the engine.

[infotechplus]

E is for engine.
you ONLY WANT air to flow FROM the booster TO the engine (don't even think about vacuum).

you want to PREVENT air flowing FROM the engine TO the brake booster

essential as otherwise, the vacuum level of th ebooster will be the instantaneous vacuum level (or boost level) of the engine.

Thanks for the heads-up guys. It always pays to confirm info.

I'm pretty sure there's nothing built-in CrUZida as I removed this from a Hilux at Pick'n'Payless some months ago when I was scavenger hoses. I thought the arrow was important but as time went on my memory regarding it's orientation has faded.

Cheers,

Peter

[TA-022]

i always thought that valve stoped air escaping the booster when at idle? wow

booster 1 me 0

[MWP]

i always thought that valve stoped air escaping the booster when at idle? wow
booster 1 me 0

The other way around.
Engine idling = vacuum in the inlet manifold = vacuum in the brake booster (what you want).

[infotechplus]

I installed the one way valve in my Hilux/Supra MA70 setup as follows:



According to the information above:



Thanks to everyone who offered assistance.

Cheers,

Peter