Check Valve for Brake booster vacuum

[rockytopmark]

Is this a standard part I can get at any parts store? Or is there a specific one for the GT?

[rrossjr]

Originally Posted by rockytopmark Is this a standard part I can get at any parts store? Or is there a specific one for the GT?

I got mine from opelgtsource.com I think it was ~$10. Looks like a pretty standard vacuum check valve with a (1/4"?) tubing connector on either end. I wouldn't be shocked if you could turn one up in a Pep Boys/Advanced/etc.
Ron in Indy

[danielcool]

A while back I read an article on how to thread the value cover to make the connection of the booster hose to the value cover more efficient. I can't find it. Any help will be appreciated

Dan
71 GT

[guyopel]

Dan the brake booster hose doesnot connect to the valve cover The brake booster hose connects to the intake manifold . The hose at the valve cover is the vent for the crankcase gasses and goes to the air cleaner.HTH

[danielcool]

Thanks, The rebuild has been 5 years. I got the handout from OGTS titled "Where do all the hoses go" but have misplaced it. I got the car along with a parts car for $700. So far I have purchased $2500 worth of parts (mostly from OGTS) and have put in another 3K on the interior and paint. The exterior is chrome yellow and the headliner is pineapple yellow (a fireproof vinyl for aircraft) Seats are black and pineapple yellow as are the door panels. It has new window rubber all around. I also had a corvette third brake light installed. I'll have some pics to post in a couple of weeks.

Thanks again

[jvandyke]

My '70 fails the brake booster test. That is; pedal doesn't move after starting car. My manifold has a valve on it, a shut off I'm guessing but I don't see a check valve. First question is does everyone have a shut off (see picture)?
Which is open (when handle is "in-line" with line?)?
I've driven the car both ways; shut off open and close (if I'm right on my guess which is which) and brakes could care less but engine idle seems to be effected.
My pedal has about 1/2 inch travel and that's it. Very hard, every so slightly goes down slowly with constant push, car stops pretty decent, took to an empty lot and panic stopped a few times. I have suspicions on the rear brakes, they don't operate properly and I'm going to rebuild the cylinders and fix or replace the lines (fronts too, well, at least careful inspection). But I'd like to get a grip on this booster deal. Since it is connected to engine idle and operation and all that. Oh, PO what did you do?

sorry, couldn't upload picture again, not sure what the problem is
here's link http://homepage.mac.com/jvandyke/vacuumbooster.jpg

[guyopel]

Need photos , a hose with a shutoff valve sounds like a heater hose cutoff , the brake booster check valve is a oneway check valve and the hose goes from the brake booster and goes to the intake manifold .I would look at the brake booster hose for a split or worn through area that is causing a vacuum leak and will give you a hard pedal . HTH

[jvandyke]

Photo is linked above, I see no in line check valve which is why I'm asking. I should be right by the manifold, no? Then to canister and to booster, or straight to booster?

[Mike Preble]

There is a large hose that comes from the area of the intake manifold below the carb and goes to a one way valve. From there another large hose goes from the one way valve to the brake booster. This hose is ~ 1/4 inch inside diameter(remember we are working with metric). There should be an arrow on the valve pointing the way the vacuum(sp) goes. Twords the intake manifold.

The only time you see a canister inline is for an engine that creates very little vacuum, such as one with a very radical cam. This canister will build up vacuum in reserve to be used for braking.

Hope this helps, Mike

[jvandyke]

Yes that helps. You can see from picture I have a shut off of some sort, no check valve and that line goes to a canister then to the booster.
Perhaps the whole booster thing isn't needed.
The collection canister in front of the brake master cylinder.
I may very well have a different cam, again, PO mods largely unknown, which stinks but it is sorta fun in a demented way.
I need to find out what was done to this car and why before I "fix" things that are already "fixed".
Is there a way to find out who owned a car based on VIN? The guy I bought it from can't remember and can't find his old paper work.
Find a "friend" who works in Mass. DMV?

[Anonymous D]

Not to repeat my posts, but an Adobe Acrobat
download, with a diagram indicating hose connections
on the Opel GT, is available for FREE here:

Engine

(See the 2nd link, for the date of June 2006.
See pages 4 and 5, and note details on page 6).

[baronbors]

Originally Posted by jvandyke Yes that helps. You can see from picture I have a shut off of some sort, no check valve and that line goes to a canister then to the booster. Perhaps the whole booster thing isn't needed. The collection canister in front of the brake master cylinder. I may very well have a different cam, again, PO mods largely unknown, which stinks but it is sorta fun in a demented way. I need to find out what was done to this car and why before I "fix" things that are already "fixed". DMV?

OH NO- then booster is very needed. You should have a hose line running out of the booster directly to the large orfice on the manifold- some where on that hose, you should have a one way check valve installed. Do not stop at the canister. The canister should have a vent line from your gas tank running to it and is a whole different subject from your braking system. Hope this helps.

[jvandyke]

anonymous D: Thanks for that, I downloaded it. I need to join up apparently, although in my case NOTHING is as Opel had it so confusion reigns.

Baronbors: Thanks too, apparently my line, with no check valve, heading directly toward the canister is just well, silly. Maybe I'm remembering it wrong. I'll stop by the parts place and see if I can scrounge up a vacuum check valve, will they know what I want? I'll try to reconstruct this all and see where I end up.

Thanks again for your input all, don't know what I'd do without you guys. Hopefully as I learn more I can give some back someday.

Update: back home, closer inspection, the canister is in fact a vacuum receiver made for this purpose, so PO is not so bad after all, think he did it because of the cam? Now, to figure out why the boost isn't doing anything. I'm about to put her on blocks and redo the brakes entirely. Probably a good idea in any event.

[opeletti75]

how long do brake boosters last for

[markandson]

Originally Posted by opeletti75 how long do brake boosters last for

As dumb as this sounds, until they break.

I imagine that their life is affected by the environment that they are in. How many hot and cold cycles they go through, winter vs. summer, how hot the summers are, etc. The only thing that really goes wrong with them is that the rubber diaphragm cracks.

[jvandyke]

Brake pedal feels a bit soft. Am going to check all fittings and bleed the daylights out of it....again.
But.
PO had installed a vacuum reserve canister, not sure why, I don't think the cam is that weird......anyway. I've got a line from intake to reserve canister, then a line to the booster. I always assumed the canister had a check valve in it but as part of diagnostics (and fun) I wanted to put a check valve in the proper spot and take the reserve canister out of the picture to see what happens.
I've always suspected the booster wasn't doing anything. I've never had a hard pedal but that could be for other reasons like air in the lines. Pedal doesn't move when you start the car while applying brake and engine idle is unaffected by brake application.
So, anyone have a part number of a check valve I can splice in-line (very near to the intake I've read, with the arrow pointed towards intake)?
BTW, when I went through the brakes last year I replaced all rubber hoses, both rear cylinders, rebuilt one front caliper and determined the other front was okay. Bleed through a lot of fluid.
PO (who marketed the car as a "daily driver") was operating on ONE brake.
Yikes. As both rears hadn't been functioning in a LONG time as evidenced by the frozen cylinders and collapsed hose. One front wouldn't grab and/or release with consistency. One functioning brake. Wow.

[namba209]

Actually the check valve for the MC booster is mounted in the booster. It's got a big rubber grommet that the check valve slides in to and the hose hooks to it. No other way to attach a hose other than the check valve. One brake working and the rest non-operational, kinda scary.

[jvandyke]

Originally Posted by namba209 Actually the check valve for the MC booster is mounted in the booster. It's got a big rubber grommet that the check valve slides in to and the hose hooks to it. No other way to attach a hose other than the check valve. One brake working and the rest non-operational, kinda scary.

Really? Where did I get the impression it was in the hose right off the intake? Sorry to bother then.

[namba209]

Having a check valve at the manifold, was considered smart practice, if the booster had a hose nipple on it, that gave you the additional volume of the hose and booster, vice just the booster vacuum chamber. You could have two check valves if you wanted.

[kwilford]

From the factory, the check valve is in the vacuum line about an inch away from intake manifold

[namba209]

All righty there now there then, Keith, I'm gonna have to check out Willit? and see if what I have in the booster is a check valve or not. If not, I'm gonna have to get one and install it at the vacuum port on the plenum. Darn, I thought I checked that previously, but that was years ago, when I had the car nothing but a shell. Just a side note, the purpose of the check valve is to maintain a vacuum in the booster so brake application will be power assisted, at least one time, with the engine not running.

[tomking]

I have parted out several Opels and my recollection is I have seen both separate check valves as well as the 90* fitting being the check valve.

[tekenaar]

Originally Posted by tomking I have parted out several Opels and my recollection is I have seen both separate check valves as well as the 90* fitting being the check valve.

Not on stock Opels, Tom . . . remember, that was during GM's "bean-counter" years, why would they DUPLICATE any function! Even my '85 Bitter SC, based on the Senator/Monza chassis and running gear, had the check-valve in the hose close to the FI intake manifold . . .

[namba209]

I guess I've got the dreaded PO disease on Willit? then Otto. The 90 degree fitting at the vacuum booster is a check valve on mine. Plus I also put one in on at the other end of the hose at the plenum. Glad I checked it, too, the fitting in the plenum was finger loose. Maybe that's why my idle is so high, and I may not have to replace the IAC.