Newbie brake bleeding question

68NewportDDD

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Little bit of background:
'68 Newport 2 door slicktop with a 383 & an Edelbrock 750 - 4BBL (aftermarket). Runs great after a major tune up.

We replaced the springs & Wheel cylinders on all 4 wheels (shoes were in good shape). Installed new lines on the back. Kept the original brake line block that is screwed in to the rear axle.

We installed a new (preassembled) MC & Booster from Leeds Brakes (great guys, very helpful). I need to adjust the push rod on the booster by about a 1/2 inch (it is just a bit too long; no play in the brake pedal)

#1 - UNCLE David bench bled the MC after we installed the pre-assembled kit on the car. He INSISTS that this is not the issue as the MC is successfully bled now. NOT what the instructions say about bench bleeding a Master Cylinder but I will defer to him on this (Arguing with a 69 year old man who is a Mopar nut is frivolous at best).

#2 - We cannot C A N N O T get fluid to the center flex hose going to the rears. The fronts bled fine...JUST FINE! Rears...not so much, even after pumping them about 37,826, 923.7 times.

I found this video on Youtube University:



I know that my 68 Chrysler Newport is not an old Chevy pickup but the logic is pretty sound in terms of the 'safety technology' for the time.

Could THIS be why we are not getting any of the stopping juice o the back? Maybe something else?

Thanks again for the assist. It is a lot of fun working on the car and getting a chance to work with my Uncle on ANY car again. Brings back good memories. :)
 
Dirt.
Remove the distribution block mounted on the frame below master and blow it out.
Blow out all the lines going to the rear from the master-back.
How old is the rear flex hose ? Change if necessary.
Clean tee for rear axle brake lines.
Do a gravity bleed leaving the rear bleeder screws open but fronts closed..have a cold beer and then later try bleeding them again.
I am at work and web blockers keep me from looking at the video you posted but I am going by experience with my 68 Newport Custom
Hope this helps.
 
Thanks for the tips!

We blew air back from the brake line on the passenger rear (where it hooks up to the wheel cylinder) and it blew all of the brake fluid out of the front reservoir and blew the lid off of the Master Cylinder; made a huge mess! It was kind of funny, kind of a Laurel and Hardy moment that we won't soon forget. I made a point to quickly clean up the mess as I know brake fluid is corrosive.

I have cleaned (thoroughly) the block feed to the rear wheels so I know that is good.

Do you have the same check valve/bolt holding your rear block to your rear axle? It has no function with the brakes but only to fasten the block to the rear axle but there is also a check valve on top of the bolt and it is hollow. Something to so with venting gas and/or liquid from the rear axle?

Next step is to replace that center flex hose. It is dirty but looks to be ok. Can't hurt to replace it.

I am going to check the block under the MC to see if it has any pins stick out of one side or the other that I can reset. I found a few other videos referencing similar issues. Sounds like something specific to dual chamber Master Cylinders.



Dirt.
Remove the distribution block mounted on the frame below master and blow it out.
Blow out all the lines going to the rear from the master-back.
How old is the rear flex hose ? Change if necessary.
Clean tee for rear axle brake lines.
Do a gravity bleed leaving the rear bleeder screws open but fronts closed..have a cold beer and then later try bleeding them again.
I am at work and web blockers keep me from looking at the video you posted but I am going by experience with my 68 Newport Custom
Hope this helps.
 
Do you have the same check valve/bolt holding your rear block to your rear axle?
All Mopars have the diff vent/brake line combo.
Make sure the vent is not plugged. the diff needs to breathe otherwise will blow out axle seals
 
I am going to check the block under the MC to see if it has any pins stick out of one side or the other that I can reset
There are no "reset" pins--just a solid chunk of brass with lines going in and out of it.
Blow out the holes in the direction the fluid flows.
 
I need to adjust the push rod on the booster by about a 1/2 inch

^This^ is causing your problem. The mc isn't returning far enough to open the port.

I watched the video long enough to see the compression fittings on the lines and got disgusted with the stupidity in the world that's now right at our fingertips.
 
Alright, thank you for the really helpful insight. :)

We also discovered that the FRONT brakes are supplied from the rear reservoir and the REAR brakes from the front reservoir when we blew that air from the back to the front.

I have a list of things now:

1) Blowout the lines from the front (I think we already did that - we initially blew them from the back to the front only because that air hose was already down there, but then we moved to the front and blew from the proper direction - will do it again though just to be safe). If that is successful it will DISPROVE the fail safe fluid shut off valve in the block. Will push air from the line at the MC.

2) Replace the center flex hose. All other rubber hoses have been replaced.

3) Adjust the brake pedal. I already knew I had to do that only because there was no play in the pedal but I DID NOT know that it could be blocking the port. So that is helpful and only reinforces the fact that it needs to be done (and I get to contort myself back under the steering wheel and the instrument cluster).
 
I had to go back and wtch but I see what you mean about the compression fittings. Not sure why anyone would do that so close to the MC (#1), and use compression fittings at all (#2).

I watched the video long enough to see the compression fittings on the lines and got disgusted with the stupidity in the world that's now right at our fingertips.
 
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Alright! After fixing the brake pedal (the push rod needed to be shortened about a half inch sp O just grabbed a different stick from the tree out back), we determined this was not the issue. BUT it still needed to be done so we went and did done it.

We push the compressed air from the loud machine (yes, before yo uas, we used the hose this time - turned out to work much better) through the lines in the correct direction - downstream from the little food & water bowls under the hood (after disconnecting the rear lines at the axle block) and no air is getting through. So I pulled the clip and unscrewed the center rubber hose (you know, the one that delivers the stop juice to the rear) and VOILA (not sure how that is pronounced WALLAH!)! Dumb hose was all clogged up. I tried running a clothes hangar through it with no luck (even greased it up real good with some left over bacon grease from my lunchtime BLT) but I could not get it to push through.

So HOWMI gonna get that hose unclogged? Maybe some Drane - O? I would like to get it stoppin' today so I can take it down the road. I am a pretty big tender foot so the Fred Flintstone method probably is not going to work.

What do y'all think? Keep in mine, I am ona pretty tight budget.
 
I understand you may be on a budget but quit dickin with the hose and buy a new one for safety sake
Raybestos number BH24058.
On our old cars cheaping out on brake related items does not pay off.
Your local parts jobber can either use the number I provided or cross reference to thier numbers.
There iss also a member here that supplies brake related parts (cannot remember who--please chime in)
More than likely an overnight item,do not be surprised.
 
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Right now is one of those Moe slapping Curly moments.

You NEVER unclog a hose... You replace it. I know you're on a tight budget as you mentioned, but brakes are one of those things that is you don't do it right...oh you will find out really fast...and ask me how.

Please run a little deficit in the budget and replace ALL rubber hoses in your system. Chance are if one is clogged, you may be looking at another once you get the new fluid in and the pressure back in those old hoses.

Should be no more that 75? For all three. I don't remember when I did mine ..I replaced everything in one shot
 
Hey there, Hi there, Ho there.... I was attempting to interject some humor in to the thread with my last posting. Apologies if it was taken differently than intended. I am just REALLY EXCITED about getting this care ready for the road and I am pretty close to being there! Should be test driving it by this weekend. This is such a cool car and knowing just about all of it's back story makes it 100 times cooler. How often does THAT happen? One of my goals is to drive it up to the dealership where it was originally sold (maybe trade it for a Hellcat? HELL NO!!!!).

Already got the center flex hydraulic hose from NAPA; just need to go pick it up. I sliced and diced the clogged hose to see where and how it had failed.

Pretty much all of the hoses, lines, fluid, and hardware in the braking system have been replaced (except for the portioning/proportioning valve under the MC and the block/splitter for the rear wheels. Certainly would not skimp on that considering the substantial loss (life, limb, & money) possible if I went cheap.

@James Romano : Indeed, yes. That is on the list to get all of the hoses and belts replaced (sooner rather than later). They all LOOK to be in good shape but I am not taking any chances. Would absolutely SUCK to have a hose or belt fail just because I got lazy or impatient and did not take the time to replace it. I had that happen on a 71 Mustang years ago and experienced my first engine fire because of it. I like the 'Moe slapping Curly moments' reference. Sounds like my Uncle David and I.

@cbarge : Thanks for looking out and thanks for looking up the part # for me. To me, that is a classy move and I certainly appreciate it and give you mad props! The member with the brake parts is @mobileparts - he has already been a great resource and I have started recommending him to others.

Got to get back to work; I will keep the posts coming!
 
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