06-09-2023, 01:02 PM | #51 |
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Re: brakes go to floor
That small reservoir is the back brakes so I assume my old brake tubing that I cut and was using for this test wasn't getting a good seal.
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06-09-2023, 01:15 PM | #52 |
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Re: brakes go to floor
That’s what’s nice about those kits, they seal and are easy to use.
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06-09-2023, 04:04 PM | #53 |
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Re: brakes go to floor
I pulled the proportioning valve brake light grounding connection to stabilize the internal slide while bleeding the back brakes and have a question. Is the o-ring supposed to be midway on the threads like that?
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06-09-2023, 04:23 PM | #54 |
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Re: brakes go to floor
No, but when you put it back in the o ring will roll back up.
Or just roll it up by hand. |
06-09-2023, 04:25 PM | #55 |
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Re: brakes go to floor
Great thanks. I'll roll it back up then.
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06-10-2023, 09:23 PM | #56 |
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Re: brakes go to floor
I replaced the master cylinder brake lines because I felt that they weren't getting a good seal. They were 51 years old. Bench testing the master cylinder shows it working well. I adjusted the back drums and they are so far out now that it is really tough to get the drums on and off. I put the bleeder bolt in the proportioning valve. Bled all of the lines again. I added fluid to the master cylinder everytime it got down halfway. That happened about 5 times. And the brakes still go to the floor. I can build up a little bit of pressure if I pump the brakes several times but even doing that, it doesn't stop the wheels from spinning. I've got it up on stands with the tires off.
Any suggestions?
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1971 C10 manual cab. 76 4x4 chassis. Cut short frame. Carbureted Blueprint 350, automatic 700r4. ~ James Last edited by K10-Kansas; 06-11-2023 at 09:19 AM. Reason: Typo |
06-11-2023, 09:11 AM | #57 |
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Re: brakes go to floor
It sounds to me like this master cylinder is either defective or damaged. I guess they can be damaged by having the pedal go to the floor too many times. It has never happened to me though. I would try another one and hope for the best.
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06-11-2023, 12:04 PM | #58 |
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Re: brakes go to floor
Can you get some pics of all the brake components on the truck? Maybe somebody can spot something
I know a guy that has a scout that had similar issues...he had his front calipers on backwards.....it wasn't until he shared pics that it was spotted
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06-11-2023, 12:14 PM | #59 | |
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Re: brakes go to floor
Quote:
How would having calipers on backwards cause the brake pedal to sink to the floor?
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06-11-2023, 02:05 PM | #60 | |
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Re: brakes go to floor
The bleeder has to be on top. If they're on the wrong side the bleeder will be on the bottom and you won't be able to get all the air out.
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06-11-2023, 03:09 PM | #61 |
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Re: brakes go to floor
I want to preface what I'm about to say, with an face-saving explanation. So,,,, I didn't know the bleeded had to be on top. I looked at my new set of calipers last week one said R so I stuck it on the passenger side and stuck the other on the driver's.
After reading Mongo's post I checked mine and sure enough, while one caliper for some crazy reason does in fact have an R on it, it also has an L. The other has an L only. I had the bleeders on bottom. I reversed them, bled the brakes and it's working perfect! Thanks a ton Mongo!
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06-11-2023, 04:30 PM | #62 |
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Re: brakes go to floor
Sweet!!!!!!!!!
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Mongo...aka Greg RIP Dad RIP Jesse 1981 C30 LQ9 NV4500..http://67-72chevytrucks.com/vboard/s...d.php?t=753598 Mongos AD- LS3 TR6060...http://67-72chevytrucks.com/vboard/s...34#post8522334 Columbus..the 1957 IH 4x4...http://67-72chevytrucks.com/vboard/s...63#post8082563 2023 Chevy Z71..daily driver |
06-13-2023, 07:52 AM | #63 | |
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Re: brakes go to floor
Quote:
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06-13-2023, 09:32 AM | #64 | |
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Re: brakes go to floor
Quote:
The brakes did seem to work well coming off the trailer and then didn't work well up on stands. The only reason I can guess why is that i had the pedal pushrod and clevis adjusted too short. But who knows because then I immediately blew a brake line.
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