Is there a place where I can buy the check valve for the brake booster? Or do I just have to find a turbo model rx7 and scavenge it for this piece?

 

dealer? parts cars?

 

almost all FC's have that valve, regardless of if it is a Turbo or not.

 

if the valve isn't working what would happen? would it cause the brakes to be "sticky" ??

 

well on a turbo model this would happen:

The brake booster needs vaccum to boost the braking pressure. If no check valve was in place, when you boost the motor, you'll have + pressure in the brake booster this = no fun.

On the N/A models I think its more of an insurance thing. Or also perhaps because they didn't want to have to change that just for us North Americans.

edit: oh, if it was there but just not working properly you could be seeing a number of different things. Like if it was stuck closed you would never have vaccum in the booster and thereby have a hard pedal and zero stopping power.

 

more erratic idle and surging brake operation.

Sticky brakes usually are from a bad master cyl or rarely a pedal lever that needs lube

 

So, even though I have a NA model I'm still going to have that check valve so my brakes will actually work during the small amount of time I'm in boost when the engine goes back into vacuum when switching between gas and brake pedals?

 

I think im actualy having a similar problem... I have to just about stand on my brakes to get them to lock... I blead them and the pads/rotors seem fine... is it my Brake Booster? Also when I pump my Brakes, the rpms drop and the car tries to die.

oh also when i pull the ebrake(which its not pulling tight enough to lock ether) I can feel the brake pedal push back alittle... didnt know if this ment anything

 

Right there with ya. Insight from anyone?

 

Try checking the check valve on your cars.. My car didnt have a brake booster check valve when I bought it. I figured it out when I boosted around the corner and couldnt stop. Autozone sells a check valve that will work. Its a GM check valve and is like 2.97. Ive had it on my car for a while and drove to cali and back with it and havnt had any problems. Brakes work perfect

 

WHERE is the check valve? Anyone have a pic of its location?

I did a turbo conversion and since I used a jspec motor - the brake booster line needed a little MODIFICATION.

Now when let off the gas and immediately brake... no brakes for a split second. Kind of scary sometimes.

Either my check valve isn't working or I removed unknowingly.

 

The brake check valve is INSIDE the rubber line thats directly out of the brake booster. Here is a old pic someone posted up a while ago of the location of the check valve.

 

Thanks for clearing that up... HELPS A LOT!

 

How do I check if it is working properly?

 

Pull it off and blow against the check valve (towards the booster). No air shall pass.

 

Am I correct in assuming that the early '86s did not come with this check valve? None of the '86s I have owned had this valve, yet when I bought a replacement hose form my car it had the valve installed in the hose.

 

God GAWD, your going to make me so inqusitive that I'm going to pull the hose off my 86 na and look. I'll probably bust the fifteen plus year old hose to pieces and.............blame YOU. Please remit to me the cost of a new hose and check valve.

 

my brakes are going, it sucks, i know the master is going, not sure if the booster is or not yet . . .

 

If it isn't functioning properly, where can I get a new one?

 

I took the line off the 86 and the checkvalve is there.

Being a SUPER DOOPER MASTER mechanic, I put the line back on............backwards.

Let me tell you something. If you can drive a RX with no checkvalve, you have enormous leg power. That sucker would hardly stop at all.

Gotta get up early in the mornig and swap that line back the right way. This car is unsafe at any speed right now.

 

Well, there's a slight difference between having a no valve, and having one in backwards.

So I assume you have a valve in yours then? Maybe it was only a Canadian thing.

 

Never seen one without it, but I guess it would be possible on the old pre-86.5 cars, since when the turbo came out they did some minor tweaks, and it is needed on the turbos