brakes Brake Booster Check Valve Orientation?

[Slightly Larger Roundies]

Which way does the brake booster valve go? White side toward or away from the manifold?

 

 

 

[John_in_VA]

There should be an arrow on it - points toward the engine.

[tjones02]

Black side towards engine

[Hokie09]

When I bought my car, the black side was towards the engine.  

 

I rebuilt the engine and brakes, and when putting everything back together, put it in the opposite way with the white towards the engine.  The brakes felt a little spongy and re-bleeding didn't rectify.  I remembered I took pics of the engine when I bought it, and realized that I had it in backwards from when I bought it.  So I put it back to black side facing the engine.  The brakes firmed up right away.  After driving about 5 miles the brakes started to lock up on me.  I reversed the valve (heard a loud WHOOSH when I disconnected it) so that the white side was towards the engine, and this released the brakes.  They are still slightly soft, but work well and don't lock up.

 

My prolonged story leads me to this: if you put the valve in backwards, can you damage it causing it to "lock up" or build too much pressure?  If the valve is in backwards, the symptoms SHOULD be spongy brake pedal, correct?

[M3M3]

if you put it in backwards, it blocks vacuum from reaching the booster.  pedal should be very hard as there will be no boost.

 

take valve out.  suck on one side.  then suck on the other.  one side you should be able to draw air, the other not.  put it back so that side you CAN pull air from is towards the engine.

 

these things can fail, so don't just put the black side towards the engine and think all will be well.  test it.

Edited June 2, 2013 by mlytle

[Buckeye]

Black side towards manifold.

Edited June 2, 2013 by Buckeye

[jgerock]

Older style valve.  Arrow points toward engine

[Hokie09]

Well in my situation the valve is not the culprit of my issues.  Right after start up and for the first few miles the brakes seem to work perfectly...feel as good as any car I've driven.  After about 5 miles or so the brakes start locking up - mostly the fronts.  If the rears are locking up at all it's not very much.  The front brakes get TIGHT.  Is this consistent with an internal leak in the master cylinder?  I just installed a new one

Edited June 9, 2013 by Hokie09

[ndog]

The oil might be going somewhere ^check all fluids

[jgerock]

Were your flexible brake hoses replaced recently?  Old ones will create issues and may act like one-way check valves for the brake system.

[Dev02]

I had a situation a little different (If I understand yours correctly) but it still might be related. I had a "vacuum" line hooked up, but it turns out it was not made for this application. For the first few minutes of driving everything was good, then it was like I had no booster. Turned out the hose would heat up and then the vacuum would collapse it, hence no booster.

 

I called Blunt and got the correct hose and problem solved.

[Hokie09]

I had a situation a little different (If I understand yours correctly) but it still might be related. I had a "vacuum" line hooked up, but it turns out it was not made for this application. For the first few minutes of driving everything was good, then it was like I had no booster. Turned out the hose would heat up and then the vacuum would collapse it, hence no booster.

 

I called Blunt and got the correct hose and problem solved.

I'm going to check this first.  I replaced almost every hose on the car and I'd be willing to bet I put a vacuum hose on instead of the booser hose.  I'm really hoping that is what I did.

 

All of the soft lines are replaced with stainless so that shouldn't be the issue.  Both calipers are rebuilt so I'm assuming those aren't the issue, plus the fact that the fronts seem equally locked-up is fishy.  Lord, I hope it's that booster hose.

[c.d.iesel]

your caliper pistons are not retracting - sticking - rust - causing the

over heating then gripping of the pads = replace calipers

 

your rubber fluid hoses are constricted internally preventing

pressure release - brakes get hotter - drag increases...

=replace all rubber hoses

 

your pads are rusted to the calipers - heavy rust -

corrosion at the pad/caliper sliding surface =

clean or if badly rusted - replace calipers

[murphykevin15]

What is the plastic threaded piece that goes inside the booster called? The piece mounted next to the master cylinder (to the left). It threads into the booster, has a hose put on it and goes upwards. 

[plape]

38 minutes ago, murphykevin15 said:

What is the plastic threaded piece that goes inside the booster called? The piece mounted next to the master cylinder (to the left). It threads into the booster, has a hose put on it and goes upwards. 

"Brake Booster Hose Connector",Rogerstii has them for about $20, sku #34331103261

There's also a rubber washer in there that does not come with the new part, but you need a good vacuum seal here, I used an o-ring and it works fine.