sohcnotec

Finished the rear disc conversion on my 96 Si.
Bled/flushed the system but the pedal is still low and soft.
Does the prop valve need to be changed? I've read all EKs share the same PV? Same part #'s ? True??
The car has ABS, so does this mean I need a special tool to actuate the ABS pump to bleed the system?
How do I get the pedal back up?

Scott-93HBSi

is the brake pedal spongey? If you pump it 2 or 3 times with the car off does the pedal get hard?

Either didn't bleed it right, or you've got a sticking/siezed capiler or slider.

sohcnotec

I wouldn't say it's spongy. Just far too low.
It gets hard with the car off after a few pumps.
I've bled the system 5 times! RR LF LR RF
All caliper sliders are free. I serviced the front and rear during the swap.

Tried 2 other MCs (15/16 + 1"). 2 other prop valves. No luck.
Bench bled the MC before putting them on.

What now?

Scott-93HBSi

I usually bleed from furthest from MC to closed to the MC.

what method are you using the bleed the brakes with?

Did you replace the booster? You know there is an adjustment where the booster connects to the pedal?

imported_ERTW

5 times may not be enough, you bleed breaks until the fluid runs clear and free of air bubbles.

scott, civics have seperate break lines for diagonally opposed wheels, so LF RR will be on one seperate line and RF LR will be on a seperate line, the sequence is therefore different from cars that only have one "circuit" for all the breaks and need to be bled starting with the furthest and endign with the closest.

sohcnotec

I tried from furthest to closest and the diagonal way.
I tried a looooong gravity bleed , the 2 man bleed ( 1 pumper and 1 to open bleeder ), and the hose from the bleeder to a container of brake fluid.

I put back the orignal MC and never replaced the BB or messed w/the pushrod/pedal height adjustments.
I know the spec between the pushrod to MC is <1mm and the pedal height is a little more than 6".

I'm gonna do a hell of bleed again see what happens.

bbarbulo

iTrader: (2)

13/16 master cylinder is too small for a rear disk conversion IMO. that's prolly why your brake pedal travel has increased, cuz to displace that much more fluid comapred to wheel cylinders it takes more volume the 13/16 can't provide.

I have a 15/16 and it's very nice, but I recently aquired a 1 inch. that's gonna kick major ***

as for bleeding procedure, the correct way is the diagonal way since the prop valve is set up that way. you don't have to change the prop valve on EKs I'm told, but I did it anyways with a USDM Si prop valve (non-ABS rear disk)

sohcnotec

Did some more bleeding last night and it seems to have got better. But not as good as I would like it to be. I want it t feel like my brother's Integra. At least it's semi-driveable now.

I'll take out the 15/16 MC and try w/the 1" MC again and see if it gets better.

I guess it just takes A LOT of bleeding. More so when you let the system run dry.
Even when you think there is no air!

Thanks guys for your input. I'll post the final results when I swap MCs for the 4th time!

imported_trackhack

If your not stuck for time, try gravity bleeding each line.
(Hey that rhymes)
Sometimes it's more effective than pumping the pedal when trying to eliminate air in the lines.