My car has been sitting still for about 4 years.
I got it running today but found that i had some brake issues.
First i stepped on the brake pedal and it went right to the floor without any resistance.
I check the reservoir and it is empty, so i fill it up.
Now after driving the car around a while, i have to pump the brakes about 5 times for them to work.
The first 3 pumps the pedal goes to the floor without slowing of the car.
The next 2 pumps the pedal is long and spongy.
Then the pedal will be firm.
If I keep force on the pedal system pressure is maintained (the pedal doesn't bleed down to the floor).
If i release the pedal for a few seconds, then i will have to repeat the pumping procedure described above for the brakes to work again.

I assumed there was a leak somewhere since the reservoir was empty, but after filling the reservoir and driving and using the brakes a lot, i couldn't find a leak anywhere, i checked all the obvious places: calipers, flex lines, T at the rear, ABS unit, master cylinder, all the lines in the engine bay.
Since the reservoir was dry, i wouldn't be surprised if there was air in the system however the pedal is rock solid after pumping it up (doesn't feel like there is air in there).

I'm thinking maybe the master cylinder could be bad?
Or there is air in the system (but really, once i get a firm pedal it is solid not spongy).
Any ideas?

thanks,
rob

 

once you pump it up all the air in the lines is compressed... I would definitely bleed the brakes first and see what happens.

It is odd that there was no brake fluid in the reservoir. I could have just been a leak in the reservoir grommets though.

 

I bled the brakes today. There was some air in the fronts.
The pedal is much better. It doesn't go to the floor now.
I guess air was the problem. Strange.

thanks for the reply eage8.

 

If the brakes are still spongy, you may want to bench bleed the master cylinder. Running it dry can make it difficult to get all the air out of the system (unless you have a power bleeder). You can bench bleed it without removing it:

https://www.rx7club.com/9459707-post10/

 

Mine sat for 3 years and had the same problem. But after I took out the master cylinder black goo came out slowly so I replaced it and had full perfect brakes after that

 

I recently put a motorcycle back on the road that had been off for quite awhile. The brake fluid in the rear system was a disgusting orange jelly. I ended up pulling the line off the caliper just to clear it so I didn't pump all that nastiness into the caliper. Hope yours isn't that bad.