JNewm
True Classic
Hi all--
I've just installed a reconditioned pedal box from MWB with new master brake + clutch cylinders. I also installed new fluid hoses from both reservoirs to the cylinders.
The back brakes seem to bleed just fine. But attempting to bleed the front brakes just yields nothing. Hardly any fluid came out of the bleed screws, then it just stopped coming out altogether. No pedal feel. Fluid level in the reservoirs not going down.
My first thought was that I hadn't tightened the tube nuts on the junction blocks enough. They're kinda hard to get at. But I cranked 'em down pretty good, and I also didn't see any fluid/bubbles leaking out of the hard lines/tube nuts when I pressed the pedal.
My next thought was that maybe one of the new reservoir-to-cylinder hoses got a kink in it, starving both front lines/calipers of fluid. But I was pretty careful to try to avoid kinks, and I couldn't see any obvious ones on a quick visual inspection. Moreover, once the box was mounted, i connected the hoses to the reservoirs with all of the bottom hard lines disconnected. Fluid started pouring out of 3/4 orifices, with the exception of the hole that's closest to the bulkhead (front side of car) on the junction block that has two orifices. This leads me to believe it's probably not a kinked inlet hose, though I did subsequently do some final tightening down of the pedal box that could've pinched a hose, I suppose. Here's an artist's rendition of what the fluid looked like with the new hoses and the new pedal box:
The front calipers are new, as are the hard-line-to-caliper hoses. I cranked the #$@$ out of the connections, but that didn't fix it. Also perhaps worth noting: I was able to bleed this system pre-pedal-box/master-cylinder.
It's both front brakes, not just one. And the biggest/most obvious variables are the new master cylinder and new hoses. Seems like it almost has to be one of those things.
My tentative thoughts:
Suspend the reservoir with a bungee cord and try again. It's a dual-chamber reservoir, and one of the hoses has to kinda curl around the back of the reservoir before feeding through the channel to the bulkhead. Maybe that hose got kinked?
One or more of the "bottom" hard lines isn't tight enough. I don't know for sure which hard lines feed the front or the back system, but it seems likely that the two hard lines that come out of the same junction block (by the brake cylinder) do so. Coincidentally, or not, those two are the hardest to get at for tightening purposes. Maybe I need to really crank on 'em with a line wrench.
One or more of the "top" hard lines isn't tight enough. Again, I bought this whole pedal box reconditioned from MWB, with the and all the hard lines on the top of the pedal box already installed. Perhaps foolishly (okay, foolishly), I didn't check the tightness of all the already-done connections before installing. I just figured no way MWB would miss something like that, but of course they could've.
New master cylinder is already shot. Always possible. Would be very frustrating.
What else?
This is a real bummer. We were planning on taking the X for a two-week road trip, leaving this week--contingent on me getting this project done, of course. Really hoping that can still happen. (I guess on the bright side, the Toyota has AC.)
I've just installed a reconditioned pedal box from MWB with new master brake + clutch cylinders. I also installed new fluid hoses from both reservoirs to the cylinders.
The back brakes seem to bleed just fine. But attempting to bleed the front brakes just yields nothing. Hardly any fluid came out of the bleed screws, then it just stopped coming out altogether. No pedal feel. Fluid level in the reservoirs not going down.
My first thought was that I hadn't tightened the tube nuts on the junction blocks enough. They're kinda hard to get at. But I cranked 'em down pretty good, and I also didn't see any fluid/bubbles leaking out of the hard lines/tube nuts when I pressed the pedal.
My next thought was that maybe one of the new reservoir-to-cylinder hoses got a kink in it, starving both front lines/calipers of fluid. But I was pretty careful to try to avoid kinks, and I couldn't see any obvious ones on a quick visual inspection. Moreover, once the box was mounted, i connected the hoses to the reservoirs with all of the bottom hard lines disconnected. Fluid started pouring out of 3/4 orifices, with the exception of the hole that's closest to the bulkhead (front side of car) on the junction block that has two orifices. This leads me to believe it's probably not a kinked inlet hose, though I did subsequently do some final tightening down of the pedal box that could've pinched a hose, I suppose. Here's an artist's rendition of what the fluid looked like with the new hoses and the new pedal box:
The front calipers are new, as are the hard-line-to-caliper hoses. I cranked the #$@$ out of the connections, but that didn't fix it. Also perhaps worth noting: I was able to bleed this system pre-pedal-box/master-cylinder.
It's both front brakes, not just one. And the biggest/most obvious variables are the new master cylinder and new hoses. Seems like it almost has to be one of those things.
My tentative thoughts:
Suspend the reservoir with a bungee cord and try again. It's a dual-chamber reservoir, and one of the hoses has to kinda curl around the back of the reservoir before feeding through the channel to the bulkhead. Maybe that hose got kinked?
One or more of the "bottom" hard lines isn't tight enough. I don't know for sure which hard lines feed the front or the back system, but it seems likely that the two hard lines that come out of the same junction block (by the brake cylinder) do so. Coincidentally, or not, those two are the hardest to get at for tightening purposes. Maybe I need to really crank on 'em with a line wrench.
One or more of the "top" hard lines isn't tight enough. Again, I bought this whole pedal box reconditioned from MWB, with the and all the hard lines on the top of the pedal box already installed. Perhaps foolishly (okay, foolishly), I didn't check the tightness of all the already-done connections before installing. I just figured no way MWB would miss something like that, but of course they could've.
New master cylinder is already shot. Always possible. Would be very frustrating.
What else?
This is a real bummer. We were planning on taking the X for a two-week road trip, leaving this week--contingent on me getting this project done, of course. Really hoping that can still happen. (I guess on the bright side, the Toyota has AC.)
