vacuum line from booster to where?? *pics*

[Guest BrandenZ]

Long story short -- got car, brakes were terrible, I investigated to find a complete absence of a vacuum line running off of the booster. Where should I run the vacuum line to?

 

 

One of the 3 I circled? Somewhere else?

 

Also.. I (obviously) don't have a checkvalve. I noticed vb wanted $30 for the valve, plus another $80 total for the hose vacuum->valve and valve->intake mani, so I picked it all up at a junkyard for $10. but uhh.. which way does the valve mount?

 

 

 

 

Thanks!

[Guest vizcounty]

correct me if im wrong.

 

I think it should go to the one in the middle with the red cap on.

 

The one on the left looks like the cold start valve and the one on the right is where the egr stuff goes.

[Synlubes]

The port with the red cap needs to go to the brake booster with the check valve inline.

The booster should hold some vacuum.

The tapered side of the ck valve goes towards intake side and the flat side of the valve goes towards booster.

The other "big" fitting can be blocked, unless you need vacuum elsewhere.

The smaller fitting could be used for the distributor or blocked if you are not using vacuum advance.

Just use some fuel hose (or simular) from the intake to the booster.

[JMortensen]

I thought that valve was a PCV valve, and the check valve was the one that is usually in the hose clamped to the firewall... Kinda like a little hockey puck looking thing about 2" in diameter. I don't have anything like that valve he's holding on my triples, but my booster holds vacuum because I have the disk thingy.

[Guest BrandenZ]

You know, I was wondering about that too. Looking in the FSM it looked to be shaped like a fat round disc. I pulled it out of the first car I came across with the booster actually attached. There were relatively new hose-clamps attached, so I'm guessing that the valve itself was replaced. Perhaps the booster and the valve were replaced at the same time. Hopefully this one will work! I tried blowing into the valve from both directions and can't seem to get air to flow through either way. <shrug>

 

BTW -- Thanks for the junkyard tip J!

[Synlubes]

In BrandenZ first pic, you can see the PCV valve at lower left of pic with the big black hose attached.

 

In his second and third pics, he is holding a / the check valve (may differ depending on model).

[Guest BrandenZ]

Update:

 

Doug -- hooked it all up per your recommendations. The hose is running from where the red-cap used to be over to the check valve, then another piece of hose is running from the valve back to the booster.

 

With the check valve in-line as you recommended, tapered towards the intake side, I get a funny sounding "psssshhhhhh" noise with the car running whenever I step on the brake. Also, after turning the car off.. depressing the brake pedal one time will cause a "pssshhhhh" noise. If I press it once more, I get no noise. Presumably one pedal press is all it takes to let the remaining vacuum buildup out.

 

However... when I press the brake, my idle drops. That can't be right. Bad booster? Bad check valve? Wrong vacuum port hookup?

[Guest BrandenZ]

Okay, update to the update...

 

I'm a tard. I originally just tacked it all together to check it out really quick. I didn't bother to clamp down any of the hoses. Once I clamped 'em all down the vacuum leak (idle dropping under braking) went away. I think that does it! The brakes are still awful.. and I swear the rears are locking before the fronts, but I have a lot more modulation with the booster properly hooked up.

 

Just one more thing.. is it normal to have the pedal travel nearly half-way to the floor before the brakes engage at all? All I hear is "pssh pssshhh psssshhhhh" as I'm depressing the brake... then a little over half-way down it engages.

 

Thanks all!

[Synlubes]

However... when I press the brake, my idle drops.

 

This could be symptoms of a leaking booster.

Pull a vacuum on the booster only and see if it holds.

Is this booster from the same year model car? (sorry if I missed it from earlyer posts)

As far as the pedal being low,

You can also adjust the brake pedal engagement height from inside the car at the rod attached to the brake pedal arm.

Have you done a complete brake ck at all 4`s?

Brake system flush including master cly + all 4 wheels.

Does this car still have rear drums?

If so, pull the drums and take a look.

Look at shoes and closely at the rear wheel cly for leakage.