front brakes won't bleed

[Ross Wooldridge]

Nothing coming from the hard lines at the connection to the front flex hoses? Sorry if this has been answered already...

Try removing the front block that delays application... ahead if the p valve, front circuit only. Should be on the driver side stub rail I believe.

 

[cuda hunter]

on the 71 chrysler ther eis only a Brake warning switch/Meter valve just below the master cylinder. There is not a separate metering valve.
However that DWS/MV is the next thing to get removed and cleaned.

 

[cuda hunter]

Or I can take the thing to my mechanic. However I would prefer to figure it out myself.
I'll try to power brake bleed the car today with someone in the drivers seat.
OPen, press brake pedal, close before pedal to floor. Repeat, repeat repeat.

 

[3C's & a D?]

I really can't see both rubber hoses collapsing at the same time, especially bad enough to not get even a few drops out. I'd replace the master cylinder first. Have you tried disconnecting the line coming off the master cylinder? If not, it's worth a shot, put a plastic bag over it, and give it a few pumps, bag dry? Bad master.

 

[cuda hunter]

Ok, So, both lines replaced with these crappy tiawanese made hoses. Cheap and quick. Going to put OEM on after a short while.

 

[cuda hunter]

Power bled the brakes with no effect.
Both lines were not clogged, but not near as clear as the new line's.
Both lines were swollen slightly as the wrench needed to be forced on the rubber hose.
Still nothing.
There was a solid point about about the last 3/4 of the pedal travel but that has now gone away since trying to power bleed it.
There is also a click now about half way through the brake pedal travel.
I purged the M/C again to make sure no line lock there. Not much to speak of. Soft pedal all the way to the last 1/8 travel, then hard push gets some fluid out of the M/C.
So, bad master cylinder then?

 

[cuda hunter]

I need to determine if this M/C is the original M/C. Rebuild or replace?
Can't seem to find any numbers.

 

[Davea Lux]

The tag on the unit is a rebuilder tag.

Dave

 

[cuda hunter]

Ok, I was wondering what that tag meant. So the M/ C has been rebuilt then.
Since I can't find numbers does this mean that this M/C is not original to the car?

 

[Big_John]

Let's ask a question or two... Was this working before worked on it? What was replaced that caused you to need to bleed the system?

Since you are working alone on this, I'm also going to make a suggestion. I bought one of these and it makes things a lot easier... https://smile.amazon.com/gp/product/B00CJ5DY16/ref=ppx_yo_dt_b_search_asin_title?ie=UTF8&psc=1


I've done vacuum pumps and they are great for doing it solo, but I had an issue with a bad bleeder valve that I couldn't pinpoint and this power bleeder helped me figure it out much quicker than asking Mrs. Big John to pump the brakes. Yea, not something for a pro shop, but great for home. Just use a c-clamp for the top that goes on the master rather than their chains. There's a bunch of YouTube videos on it.

 

[PH27L7]

That's sure looks like an original, never touched MC to me. The tag should have the last 4 digits of the part #.

These brake systems are really not that complicated, you need to work your way down the system to see the point where you're getting no fluid flow, starting with the MC. Have you opened the MC connection to see if fluid comes out? It should be a steady drip-drip on the disc side. I suspect you have a whole lot of rusty crud in the system from not being flushed in 50 years. Gravity bleed on the front discs should be easy peasy with the differential pressure switch centered.

 

[cuda hunter]

Cool. @Big_John I will look into that and purchase.

The car had no work done to it. I showed up to drive it home and the brake system had gone soft over night.
The guy had driven it some 200 miles before I purchased it. I think it had been like 3-5 months since that trip and it sat outside that long. The seller was very surprised that it had happened and of course it happens when I show up to drive it home.
Other than that I have no history.

 

[cuda hunter]

I've removed and replaced all the brake fluid.
Gravity bled the rear system with no issues.
Front won't gravity bleed. At first I could get drips out of the M/C after purging the disk side. But now I purged it again and I don't seem to be getting anything out of the disk reservoir. So on this car I deduct the M/C is bad and needs rebuilt or replaced.
That's why I am trying to figure out if it's original or not. If not, I can have one pretty quick.

 

[cuda hunter]

My goal for today, maybe, is to remove replace the caliper on the blue newport and see if that stops the passengers front caliper from sticking. If I can get that to not stick, I will remove the non original M/C on the blue car and install it on the gold car. This way I can figure out if it is indeed the M/C on the gold car. Switch and swap and see what happens. At least this way I will put together a plan.

 

[cuda hunter]

This is what the brake fluid looked like when I started and what it looked like when I had replaced it all.
The rear drum lines bled out great and clear.
The fronts just won't bleed past the M/C apparently.

 

[Big_John]

Cool. I will look into that and purchase.

The car had no work done to it. I showed up to drive it home and the brake system had gone soft over night.
The guy had driven it some 200 miles before I purchased it. I think it had been like 3-5 months since that trip and it sat outside that long. The seller was very surprised that it had happened and of course it happens when I show up to drive it home.
Other than that I have no history.

Ahhh... The unknown.

I tend to shotgun stuff like that. Yea, it goes against my "diagnose the problem" mantra, but sometimes you're money and time ahead to start from scratch.

Since the system "went soft", and the MC looks like it's been there a while, I'd say it's a good candidate for replacement. My experience with old master cylinders is once the MC piston goes outside its normal path (pedal hits the floor) the rubber tears itself up on the worn cylinder or gunk and if you're not replacing it now, you are next month. It may be your problem and of course, it also may not be...

It's the brakes... Do it once, do it right.

EDIT: Just saw the pics above that weren't there while I was typing with my two fingers. Replace the MC, calipers, wheel cylinders and hoses. Flush the lines.

Yea... The seller was "surprised".

 

[cuda hunter]

@Big_John
I bought it. Be here Monday. That's pretty cool! Sure helps with being alone. The lady hunter did not enjoy sitting in the hot car pushing the brake pedal. So difficult.

 

[cuda hunter]

The car had sat in his grandpa's garage since 1984. Was pulled out last year by the daughter and sold to the grand son. He drove it some hundreds of miles and parked it. Decided he couldn't take care of the car and sold it to me. So it did indeed sit for 27 years. At least that's the last registration I could find.

 

[cuda hunter]

I will be rebuilding the full system.
Big question is if the M/C and the power booster are original.
If original I will rebuild, if not I'll have the parts shipped from @mobileparts

 

[PH27L7]

With the looks of the crud in that MC you're lucky your lines aren't swiss cheese. Hopefully when you're running down the road one doesn't decide to let go. I'd bet the insides of your calipers are a mess too. Like stated I'd go through everything if you value your safety.