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  • August 13, 2022, 03:01:05 PM

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Author Topic: mysterious brake issue  (Read 13230 times)

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Offline packotobacco

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Re: mysterious brake issue
« Reply #30 on: January 21, 2017, 12:50:13 PM »
Vacuum thing didn't work so i tried the super long hose from bleeders to reservoir thing. 20' was plenty long enough to route to the drivers seat along the way. Did that so i could kink the hose while releasing the pedal to simulate a closed bleeder. Doing this made it very apparent that air was seeping past the threads on every bleeder, cured that with Teflon tape. When i got to the front right line i got down to super tiny bubbles but they wouldn't stop so i tried the pump and crack method and got endless stream of larger bubbles. Under that method it couldn't be threads or hose letting air in. Is there a spot that could suck air in at low pressure but not leak under the much higher pedal pressure? Btw fluid level doesn't drop but it raises when more bubbles appear

Offline AMC1

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Re: mysterious brake issue
« Reply #31 on: January 23, 2017, 04:00:42 PM »
I've never had bleeder screws leak once they were tightened down. I sure wouldn't trust the brakes to Teflon tape. Rebuilt wheel cylinders which include new bleeder screws are inexpensive maybe $5-8. Calipers of course are more expensive. I just can't imagine all four leaking.
1976 gremlin
pair of 1983 SX4's sports
1946 Cushman step-thru

Offline mudkicker715

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Re: mysterious brake issue
« Reply #32 on: January 23, 2017, 04:51:52 PM »
Teflon tape does not belong there ever for sealing purposes. You have issues that are not being said somehow.



Manitowoc WI

Offline packotobacco

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Re: mysterious brake issue
« Reply #33 on: January 24, 2017, 02:18:57 PM »
The teflon has nothing to do with my issue. Only used it to keep air from sucking in on release as i had no helper at the time and the mightyvac kept sucking air past the threads. That said i made a motive bleeder and will post results after i finish.

Offline mudkicker715

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Re: mysterious brake issue
« Reply #34 on: January 24, 2017, 03:34:28 PM »
For bleeding brakes i only gravity bleed. Meaning open the fartest point on back till only a stream comes out than the closer point. Same on front. This works well even on my navigator. Unless a rubber hose is pinched like on the previous vechicle i mentioned.



Manitowoc WI

Offline eagleman

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Re: mysterious brake issue
« Reply #35 on: January 24, 2017, 06:03:59 PM »
Have you considered using a pressure bleeder. I have one and you pressurize it to sixty pounds  and it has a cap that fits over the master cylinder. It will for sure bleed your brakes and any leaks will also for sure show up. The one I have is made by Wagner and are rather pricy but you might find on for rent and any tool rental place or some auto parts store that also rent tools.
Turkeys walk.Eagles fly!!!

Offline packotobacco

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Re: mysterious brake issue
« Reply #36 on: January 27, 2017, 07:20:00 PM »
I just built my own with a $10 sprayer can, a 1/8 hose fitting and an air nozzle with a rubber tip. As for psi I just stick the nozzle in a cheapo gauge i keep around and count the pumps. Total cost twenty bucks but thats w/o the gauge and master cylinder cap. Took mine from my first rebuilt unit that didn't work and drilled a hole just off center so i could still use the wire for the cap. I was told 30 psi but I'll try 60 if 30 doesn't work. The spray can will do just air or you can fill it with brake fluid to avoid refilling. Can't wait to test it out, fingers crossed.

Offline AMC1

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Re: mysterious brake issue
« Reply #37 on: January 28, 2017, 04:10:23 PM »
I use to use air pressure until my canister exploded & I had brake fluid everywhere. Your paint job will not like it. I've never had  a problem since with simply putting a bleeder line in a jar with fluid. Air can't back up. If you have an opening somewhere else that's a problem.
1976 gremlin
pair of 1983 SX4's sports
1946 Cushman step-thru

Offline packotobacco

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Re: mysterious brake issue
« Reply #38 on: April 05, 2019, 05:44:55 AM »
Hi again finally back for more punishment.had to give up for awhile because I had to move. No room at new place so it's been in storage, but now I have a driveway again so I'm back at it. The pressure bleed didn't work so I recently gave up and handed it over to a highly recommended shop. $500 dollars and two months later he gave up and handed it back. But supposedly he got rid of the bubbles completely. And he definitely improved the stopping power, but only a little bit. So currently a full depress engages the drums quite well while running but not the discs. I'm thinking it must be a pedal / rod travel issue, as that could explain the weak bleeding pressure and thus why I could never clear all the bubbles AND the soft pedal while running AND the drums working but not discs. Does that make sense or am I way off base? I did check the booster pushrod adjustment but I don't remember comparing the length of the rod that connects the rear of the booster to the pedal. Can anyone get me a measurement for that? Thank you all for your help and info, without this forum I'd be lost and have to scrap an otherwise good running American treasure

Offline packotobacco

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Re: mysterious brake issue
« Reply #39 on: July 03, 2021, 07:01:56 PM »
Hi there I know this topic has been dead for a while but I finally have some answers so I figured I'd put them down. I recently took my eagle to a shop that's had at least some experience in working on them. After replacing some of my brake lines my constant bubble issue finally disappeared, thank the eagle Gods. Then they replaced most of my exhaust and found a leak at the exhaust manifold. I'll explain how me and countless cans of starter fluid managed to miss that, later. Got in some testing in the parking lot and had a high firm pedal. On the way home as some of the computer stuff kicked in, my vacuum dropped off a bit and my pedal got spongy. Got home and checked vacuum and lines reconnected one that the mechanics had capped. Checked the timing and spark plugs and everything seemed perfect, However, IT STILL RAN LIKE CRAP AND LOST BRAKES UNDER LOAD.

Obviously, something must have still been wrong. I busted out the mental thesaurus and tried every search term I could cobble together to find information about timing a 258 engine. Eventually I decided to pull the distributor and realign everything manually. Found TDC with a flashlight through number one sparkplug hole, checked valves through the oil fill cap.

Here's where it gets interesting, I went to reinstall the distributor and found the number one cylinders rotor position, UNDER THE SPARK CABLE FOR CYLINDER NUMBER SIX. That made absolutely no sense to me until I realized that, if the distributor is 180° out the engine won't fire on number one cylinder but number six will still fire as it is on the compression stroke at that time and you can turn the dizzy almost enough to time it to number six when it's reversed. Which is why my timing sounded worse the closer I got to the timing mark, if I had put the inductor for my timing light on the number 6 cable I may actually have been able to time it, but that would have rendered the timing mark useless.

Suddenly every problem I've had for years has a single explanation that makes sense, my vacuum testing for the brakes was worthless because the idle had to be tuned so high that I would have had full vacuum with a hole in the manifold, I never found the vacuum leak because the mixture was so rich it was a drop in the bucket, the bubbles weren't the cause of my spongy pedal they may actually have been a symptom, ie excessive vacuum due to idle, and my computer actually keeps my engine from trying to die now instead of killing it. Yay!

I'd like to say a quick and final thank you to not only the members who have helped me on this post but all the members whose information has helped me along the way seriously could not have done it without you.

BTW, if you have questions I'm on the site a lot more than I post so feel free to ask.

Offline AMC1

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Re: mysterious brake issue
« Reply #40 on: July 23, 2021, 11:08:36 AM »
Now that you seem to have solved the problem I'd like to know How high off the floor board is your brake pedal with the engine running & having successfully applied the brakes.
1976 gremlin
pair of 1983 SX4's sports
1946 Cushman step-thru

 

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