Vacuum leak?

[EMSjunkie]

Finally got my Coupe legal for operation on the street.
been driving the snot outta it  

have noticed that when I step on the brakes, the engine speeds up
just a little  :?

small block chevy. dual diaphram vacuum brakes.
moderate cam.

is this normal  :?:

I have also noticed a small leak at the back of the master cylinder.
figger it dried a little sitting for 4 years  



Vance

[enjenjo]

Does it have a vacuum check valve in the line from the mamifold to the booster? It's usually the fitting the hose connects to at the booster. That may be bad. The way it's supposed to function, the vacuum will be stored in the outside chamber of the booster, and when you step on the brakes it goes into another chamber to boost the pedal effort. If it's working off manifold vacuum all the time, either the valve has malfunctioned, it's missing, or the booster has an internal leak, and bleeding the vacuum off all the time.

[EMSjunkie]

Thanks Frank  
I believe it does not have a check valve between the booster
and the manifold.

there is an elbow at the booster, don't know if there is a check valve there or not.  :?

guess I'll do some checkin' after a little nap.
just came off a straight 48 hr. shift.  :x


Vance

[Crosley.In.AZ]

Thanks Frank  
I believe it does not have a check valve between the booster
and the manifold.

there is an elbow at the booster, don't know if there is a check valve there or not.  :?

guess I'll do some checkin' after a little nap.
just came off a straight 48 hr. shift.  :x


Vance

the elbow usually  is the check valve assembly that enjenjo mentions.

you can see through the elbows that are not valves