Dr Diff front disc conversion 68 Road Runner

[Thunderlugs]

I would agree with rrTor Red. Clean all the crap out with air and brake clean. Lines , and hoses! You could be seeing residual crap from last weeks turmoil with the bad master. I'm also on board with loosing all the teflon tape. That stuff can be menacing. Good flares and tight fittings make the seal. Sometimes that air can be a Bitch to purge!.Always bleed from the furthest wheel to the closest to the master.

 

[rrTor-Red]

I'm also on board with loosing all the teflon tape. That stuff can be menacing. Good flares and tight fittings make the seal. Sometimes that air can be a Bitch to purge!.Always bleed from the furthest wheel to the closest to the master.

I agree, Thunderlugs. On my brake conversion though, the flares just didn't do the trick. I know it had good flares on all lines. I had to use something like Teflon but it was like a paste. For the life of me, I cannot remember the stuff and I'm not at home at the moment to check. Anyway, I used a simple Q-tip to apply this stuff but I put it to on, leaving about 3 threads exposed. I then re-installed, tightened, and no more leaks.

 

[Billccm]

Dr Diff says it's time to press the brake pedal, but I'm not going to do that today. Here is my email reply to Dr Diff:

Thanks for being patient; I’m not claiming to be a mechanic, but I’m not stupid, either.

After last Friday night’s fiasco, I’d rather not touch the brake pedal until I’m convinced this is the last thing to do.

Anyhow, let’s go from the top again. All new brake lines from InLine tube, new rear wheel cylinders.

With a Mityvac, I can get a good bled on both rear wheels. Done.

I cannot get a vacuum, or any fluid at both front calipers. Crack the bleeder and vacuum falls to ZERO. Teflon taped the bleeder, crack 1/8th a turn, vacuum falls to zero.

Must be sucking air somewhere, right?

Remove line from Master Cylinder to proportioning block. Place finger over one side, Mityvac the other side, and vacuum holds. This line good; reinstall.

Remove line from proportioning block to driver front. Test with Mityvac and vacuum holds. This line is good.

Can’t easily remove line across firewall, so pull line at flex hose and apply vacuum. I get some fluid and bubbles, but vacuum can’t hold? Drops SLOWLY?

Reinstall passenger side line at flex hose.

Loosen and retighten all three lines at proportioning block. Tighten per instructions. These lines are tight!

Still cannot hold a vacuum at either caliper?

Can a proportioning block have a leak? Doubtful, right?

Lines are new. I inspected for any cracks.

I don’t know what to try next. If I pump the pedal I’ll just suck air back into the master cylinder and that won’t help.

Got any ideas?

Thanks, Bill

 

[Billccm]

It's unfortunate, but I'm done for the next three weekends. Travel and family visiting. Cleaning up the garage and putting the tools away.

I'm in a bind in that I could have the car towed to a brake shop, but if they find a defective caliper, porpoitioning block, etc I'd just have to have the car towed home. There is a mobile car repair business in Tucson I might call next month as I am just out of tricks.

I did try some teflon tape at the propoitioning block; no difference.

The only good news is the rear brakes are bleed and I have yet to see any issues with any leaks, etc.

I'm going to go for a long shot; could a caliper be sucking air?

Thanks for all of the help.

 

[69L48Z27]

Sorry to hear your having so much trouble with this project. I agree with the Doc, push the pedal. I did my disc brake conversion today and I re-bled everything. I used my hand vacuum pump to try and draw fluid but the passengers side wasn't having it. I threw the kid in the driver's seat and yelled UP/DOWN a few times and I had fluid. I then worked around the entire car bleeding with that method.

If you crack the bleeder while pressure is applied, then close it before the person lets up on the pedal, it will not suck air in the MC. You'll also find the problem pretty fast if you have one.

Vacuuming and gravity do not work well for me. Ever. Pedal pressure is my 'go to'.

 

[Fran Blacker]

Agree with 69L48Z27 get it so you can have a helper push the pedal. I like pump the pedal 3 times pretty fast and hold. If you have a leak you'll find it fast! You don't have to worry about sucking air. Long ago bought a syringe type reverse bleed, push through from bleeder, waste of money!

 

[Billccm]

Well, I pulled both front bleeders completely out four hours ago and left the caps off the master cylinder. NOTHING. No drips, no fluid anywhere.

Fellow local mopar guy asked me to check the 'spool' in the porpoitioning block. Claims the spool might be screwed up. I took an ohm meter, and the brake safety switch is not grounded. Is this a clue?

 

[Billccm]

I did the 'pedal push' last weekend. I got one good hard pedal pressure push, then nothing. Is was like the master cylinder disappeared from the brake pedal. Bench bleed again, and never got any master cylinder action from there on out.

I'm out of town for awhile. Just throwing in the towel and will have the car towed unless somebody has something else for me to check. This is weekend number two of just doing the same thing over and over and I'm getting nowhere.

 

[Billccm]

anyone ever heard of opening one front and one rear bleeder to clear a 'stuck' portioning block? Googling around shows some similar symptoms to mine.

 

[Fran Blacker]

You think the propo valve is stuck so no fluid is going to the front brakes? right. I'd open just rear driver side bleeder and put a hose on it to direct fluid to make as little mess as possible. then go stomp the brake pedal a few times. Have you tried to crack the front brake line where it goes into prop valve? If you get fluid there tighten it backup. Then the outside of propo valve to one of the front wheels and crack that no fluid propo the problem. Wonder if you reversed the front and rear lines on the propo valve to see if the problem reverses. don't think it's practical.
I did the Mopar Action disc swap and used a E77025 master 1" bore for manual brakes, worked fine. Power they used a E75818 master for power brakes. I assume that is an EIS number. Think I read along in one post your using a 15/16" master?
Wonder if the above brake stomp doesn't work try one of these.

 

[Billccm]

Yes, 15/16 master cylinder.

No fluid at proportioning block output for the fronts.

Proportioning block input line has a few drips when I crack it, but no stream.

 

[AMX364]

You have gotten rid of any Teflon tape or paste in the system? I did read the complete posting from the start and my question is are the Inline Tube brake lines Stainless Steel? Or regular steel brake lines. SS brake lines are very hard and have trouble sealing. Standard steel brake line are softer and will conform to the fitting better as far as sealing. If they are SS the more connections that you have the more likely you can have sealing problems, would also translate to bleeding problems and leaks. Just a thought.

 

[Billccm]

You have gotten rid of any Teflon tape or paste in the system? I did read the complete posting from the start and my question is are the Inline Tube brake lines Stainless Steel? Or regular steel brake lines. SS brake lines are very hard and have trouble sealing. Standard steel brake line are softer and will conform to the fitting better as far as sealing. If they are SS the more connections that you have the more likely you can have sealing problems, would also translate to bleeding problems and leaks. Just a thought.

The teflon tape (recommended by mityvac to keep air from blowing through the bleeder threads) is now gone. The front bleeders are still off the car, the caps off the master, and my garage floor is bone dry.

 

[rrTor-Red]

SS or aluminum lines, Bill?

I used a little paste on mine because mine are all SS and as AMX stated. I'm glad I did because if I didn't, and used regular fluid instead of DOT 5, I don't want to see my paint bubble

 

[AMX364]

SS or steel.

 

[Billccm]

All regular steel lines from InLine tube. No stainless.

Inspected flares. They look good.

 

[Billccm]

Talk about a long running (painful) thread.

I'll spare you the details other than I had one of my good A Body friends come by and help today.

I have one new InLine Tube line that refuses to seal on either end. This is the line from the proportioning block to the driver side hose (shortest line). I have loosened, re-torqued, loosened, re-torqued, and tightened REALLY tight. Both ends leak badly.

Any advice?
Thanks, Bill

 

[rrTor-Red]

Call Inline and get another line

 

[NJRR]

If it's a short line without crazy bends, get a line from the local auto parts store and a double flare tool. Make a new one.

 

[Billccm]

If it's a short line without crazy bends, get a line from the local auto parts store and a double flare tool. Make a new one.

Well, I have been to NAPA, Parts Plus, and even a few brake shops, and I can't get the smaller fitting that fits the flex line end.

Any sources out there that will sell me just this line?

BTW, InLine tube will not support me since I bought from the InLine tube store on eBay.