Hello, i have been dealing with a major brake issue for about 2 years and i cant seem to find the info im looking for to fix this problem, i have a 1992 trans am, i swapped the rear brakes to disk brakes with a conversion kit from right stuff detailing, and the front brakes are wildwood 4 piston calipers part number 140-7675-D. I have installed a wilwood master cylinder 261-13269-bk which has a bore size of exactly 1 inch as well as proportioning valve that came with the master cylinder, i have tried gravity bleeding which i got a little fluid out but as soon as i started trying to pedal bleed it the fluid no longer flowed, i have gotten no pressure to the rear brakes at all no matter what position the prop. valve is in, i need to know what the best option is for a new master cylender and proportioning valve so that i can get fluid out to the calipers, i have the oem brake booster, oem pedal ratio and all new lines, i have verified that there are no leaks in the lines.

If any one here has experienced this or knows what i should do please let me know, if i need to get different parts i will, i just want to get this finished so i can drive the car.

 

Give Wilwood a call

 

you are most likely missing the wilwood 'rod' that goes between the master and the booster.

but two years?

thats a bit excessive

 

I had a really hard time getting fluid to the rear calipers when I replaced the entire brake system with new parts. I ended up borrowing a pneumatic air bleeder from a friend which worked to get fluid / pressure to the rear brakes. The tool was a Mityvac MV6870. Not sure if you could rent one from Advance Auto or AutoZone

 

If you remove the rear line, from the master, pump the pedal, does the master push fluid out of that port?

If yes, move tot the prop valve...same test....if yes, continue rearward. Where do you lose fluid flow?

 

oh also, you need the prop valve tool if you have a stock style one.
without it, the prop vlave will default to one side, usually the front and not allow fluid to the rear.

 

Did you bench blend the new master? It's totally necessary w a new one. You can pull/ vacuum bleed all you want. It won't pull the all air out of the new master. Also, if you're using a wilwood adjustable prop valve, make sure it's open for the rear brake adjustment. Also, are you sure the wilwood MC is comparable w your booster? The 1 inch bore is fine and should be good w the wilwood brakes. My MC has a 1in bore and is great w my wilwood setup.

 

I do have the little push rod thing In there, and its been an on off project, i have had alot to focus on with the car

 

I do get fluid from both lines, ill have to do a deep dive into pulling it all apart and following the pressure to see where I loose it

 

Cool...you tested and know something....more than a lot are capable of, on these here forums. Good feedback. I'd likely look here first....

 

Bleed the master cylinder, put plugs in it and see if it is rock solid. If so keep going down the line. If it's not rock solid with the ports blocked, you have air or a bad master cylinder. I've had to open the rt. rear wheel bleeder and push fluid then close the bleeder one stroke at a time to get fluid to flow to the rear.

 

You can simply open the bleeder (or multiple bleeders) and pump the pedal (with the bleeder(s) open) and move/force fluid out to the caliper(s) w/o pulling air back into the master...or any other critical component. Easy button.