Rear Brakes Locking Up

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Andronikos

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That would have been my answer on post 7
if post 6 had that picture . Post 6 and the picture at post 907 was what gave me what I needed to see the problem.
So like Auroragirl you also can't understand written English? You guys need pictures?
 

Ricko1966

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So like Auroragirl you also can't understand written English? You guys need pictures?
Absolutely,I read in post 6 that you had the fronts routed to the rear port on the master. You didn't say the rear port is the small reservoir,and all masters are not the same. As soon I saw your pic and read post 6 the problem was evident. Evidently you can read,heck you could even look at all the parts,you couldn't solve your own problem. I only needed 1 Pic,and post 6. Thanks, you ever hear the saying a picture is worth a thousand words? Go count all your words after post 6 until you posted that picture. That picture solved it for me without 1 more word from you necessary. Just think,you could have saved 4 pages of posts and already had your truck fixed by now.
 
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Keith Seymore

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ever hear the saying a picture is worth a thousand words?
I had a boss once that wanted the picture - and the thousand words.

Good grief. If he ever wrote a book the whole thing would have been on the title page.

K
 

Sad Sack

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Hey just checking. :)
I've seen more than one set of brake shoes ruined with new drums being installed before removing the cosmoline. It certainly makes the brakes lock up way early... ;)
Yup, contaminated brake shoes are not what the doctor ordered.
 

Sad Sack

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Pics add so much more context that most people lack the skill to describe with just words as most people are not authors.

glad you got your issue solved.
And cell phones make it so much easier nowadays. Three best tools ever are forums like this, YouTube and phone cameras! I could have used these back 50 years ago when I got my first car, would have saved me from so many headaches.
 

AuroraGirl

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It's not my fault you can't understand written English. Get off my thread.
well with an attitude like that im more than happy to be a nuisance

You already asked me to be nice and I apologized and turned the tone down. And Im not the one who needed to be asked by numerous people to see your master cylinder before you finally did. Early on this discussion the possibility was brought up more than once and you dismissed it.

I can be wordy but I am very much not struggling to read, especially between the two of us.
 

AuroraGirl

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Absolutely,I read in post 6 that you had the fronts routed to the rear port on the master. You didn't say the rear port is the small reservoir,and all masters are not the same. As soon I saw your pic and read post 6 the problem was evident. Evidently you can read,heck you could even look at all the parts,you couldn't solve your own problem. I only needed 1 Pic,and post 6. Thanks, you ever hear the saying a picture is worth a thousand words? Go count all your words after post 6 until you posted that picture. That picture solved it for me without 1 more word from you necessary. Just think,you could have saved 4 pages of posts and already had your truck fixed by now.
thank you for the measured and meaningful push back, I posted my reply before seeing yours.

I do remember the distinct "multiple master cylinders, they can be different based on which one, and the 80s have low drag disc brakes which adds another layer of double checking required"

The only thing we learned from his answers to that collective discussion was that he had low drag disc brake master , but nothing about the lines. because he used an amazon photo.

Quicker he realizes we are here to help each other and share experiences with our collective wisdoms and not to bite or waste time, quicker we all would be happy and get along.
(at least since the political hot headed ness turned down from the past)

I for one can be nice and helpful in the future, because theres 0 chance I remember his name by the next time he posts a thread, so I would treat it like a new person lol, but this behavior might lead to more senior/active members not chiming it if they remember. Hope he comes around and cools off
 

AuroraGirl

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Hey just checking. :)
I've seen more than one set of brake shoes ruined with new drums being installed before removing the cosmoline. It certainly makes the brakes lock up way early... ;)
True, a lot of people don't realize that the braking surfaces are left machined ready to go, and to not rust they oil and bag the drum /disc
Without the machined surface and having rust, you'd have to brake a bit before being able to get your brakes adjusted to be able to set them accurately

The brake shoes material are different than discs and the linings need that coefficient of friction they were designed with to give proper feel. The self-energizing nature really shines with backwards shoe installation and Really really shines with contaminated linings.

My f150 I had done the drum brake and I put the shoes on backward, but the adjuster (bendix type) hardware was aftermarket junk, and the lever wasnt horizontal and properly on the adjuster wheel, that allowd the adjuster to keep ratcheting out the shoes ,and I locked up the brake in my driveway , only wouldnt lock up fully in reverse
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This isnt the same angle but you can see in the photo I have the shoes swapped around, and the old adjuster lever installed on the second photo. To my knowledge the squares dont use this type of drum brake, at least not in the half tons iirc, but use delco-morraine style which uses a spring in the hook wire that operates the adjuster and looks different. but its a good thing to see if you are doing drum brakes, check the hardware
 

legopnuematic

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low drag disc brake master
Is that what the difference is (besides materials) between the cast iron and aluminum/plastic masters?

Learn something new everyday.
 

AuroraGirl

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Is that what the difference is (besides materials) between the cast iron and aluminum/plastic masters?

Learn something new everyday.
Yes, to my knowledge the low drags will always have plastic and the reservoir is now somewhat combined more than it was on the metal(the metal seem to share fluid above half way, or divided entirely) , the plastic ones either have a divider too or a float or something to prevent hydraulic failure if you have a non combination valve system and a line blows

The 1980 model year i think was the first year in cars and trucks for low drag, i have a 1979 cutlass and a 1980, the 1980 has a plastic one
The primary piston has more diameter and pushes more fluid than the old design because the retracting of the piston requires more volume to overcome

In the service manual, ive looked before, the trucks without low drag are just like the metal ones, of course the design still depends on the manufacturer, theres multiple latches and shapes , some have a trailer brake port etc

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Something I just learned googling it
 

AuroraGirl

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I dont know if the OP brakes look like this but in my research I thought these diagrams were nice and very detailed, this is a troubleshooting for brake drag from the cables which I dont think he has issues with.
 

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