Brake Question...Again
 

Thanks Giovanni for rock auto link. I searched and found master cylinder for 1987 s10 2.8. Site said to look on master cylinder reservoir for j3 or j1 code. When I did this the master cylinder had no code and matched and after market product and looked to be in good shape. What looked untouched was the brake booster. 25 years plus...so my question is should I replace the brake booster instead of the master cylinder? Original problem is brake pedal all way to the floor.
Thanks for any reply.

Nah, only replace the booster if you hear it hissing when you hold the pedal. Boosters are fairly simple things and dont fail often.

Pedal to the floor is gonna be the master cyl.

Rockauto is a great place to buy from.

Thanks ohsofly,
I checked again and for sure it hisses but when depressed and as I am depressing the pedal to the floor. Did you mean hissing when pedal is on the floor and constant sound?
Sorry to be slow about it but making sure I do not do double work.

if the booster goes bad it will just be like not having power brakes. kinda like if you get in your car and hit the brakes a few times with it off, the pedal is still towards the top its just really hard to push. but yeah if its going to the floor you got a master issue or a blown brake line somewhere

Just want to verify....

- Have you checked to see that you are not leaking fluid?

- Have you bled all of the air from the system?

Thanks for the tip and finally got car out of storage and had breaks checked. No leak but it was the master cylinder. Also front pads needed replacing and previous owner put the rear shoes on wrong and front rotors needed turning. Usually I can do brakes but it was good to have the car put on the lift and check lines and other stuff. Will make now post for "what now?" for other list of "to fix". Still weary as I hear soft "hiss" when braking but like you all guy assured me "I will know when brake booster goes out".

a soft hiss is normal,its just the fluid etc moving. the kind of hiss we are talking about is a vacuum leak. If you want, open your hood and you will see a round black ball with a rubber line on it. while the engines running,unplug that hose and listen. you'll hear that air moving hiss we were talking about. Engine might run funny until you plug it back.

Great will check today!

by the way,that ball has nothing to do with this subject at all. I was just showing you a way to hear the noise we were referring too.

Gotcha now maybe you can look at my laundry list under what to fix now
thanks again for your help