Broken brake cylinder?

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rupert's
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Broken brake cylinder?

Unread post by rupert's » May 13th, 2020, 5:57 pm

Hello everyone
I don't know how the master brake cylinder works (the one behind the pedal). Mine when I took it apart for restoration I don't know if it worked well. Now I want to mount it again but I don't know if it works correctly.
I have sunk it with the pusher but it no longer comes out. Does this mean it is broken? Is there any way to check it?
Greetings to all!
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Rossco
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Re: Broken brake cylinder?

Unread post by Rossco » May 13th, 2020, 8:20 pm

Hi
Have you got all the correct parts, seals etc. plus the internal return spring assembled in the right order?
Are you using new seals and is the cylinder bore in good condition free from scoring and/or corrosion?
Otherwise there is not much to reassembling these brake master cylinders?

Rossco
1973 M-151A2
1960 Seagrave LAFD Hook and Ladder Fire Truck
1953 M38A1 Jeep
1998 Ford Escort XR3i
2007 Ford Focus ST 2.5

Hambone
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Re: Broken brake cylinder?

Unread post by Hambone » May 13th, 2020, 8:35 pm

You can put it back together and bench bleed it, run a clear hose back into the reservoir, make sure it pumps, manually pump slowly with screwdriver, purge all the air, then let it sit awhile and check for leaks around the seal area. Make sure you have a clean bore area, if it's not pitted too bad, you can hone it with a brake cylinder hone.

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m3a1
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Re: Broken brake cylinder?

Unread post by m3a1 » May 13th, 2020, 9:37 pm

Hambone wrote:
May 13th, 2020, 8:35 pm
You can put it back together and bench bleed it, run a clear hose back into the reservoir, make sure it pumps, manually pump slowly with screwdriver, purge all the air, then let it sit awhile and check for leaks around the seal area. Make sure you have a clean bore area, if it's not pitted too bad, you can hone it with a brake cylinder hone.
....or buy a new one. Your life and the lives of others will depend upon this single component.

I'm not saying that you're not capable.

It's more a matter of your deciding, right now, who a plaintiff's lawyer might want to chase in the off chance things go wrong.

Would you rather it be you he pursues, or would you rather it be the master cylinder manufacturer?

Cheers,
TJ

Hambone
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Re: Broken brake cylinder?

Unread post by Hambone » May 13th, 2020, 10:01 pm

Misunderstood, thought you had rebuilt it and the bore was dry, as TJ said, you can buy a new one for $70 or rebuild yours for $40, being the removal and replacement is a PITA, go back with new or rebuilt.

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svramselaar
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Re: Broken brake cylinder?

Unread post by svramselaar » May 14th, 2020, 5:58 am

hi

below the kit
https://www.worthpoint.com/worthopedia/ ... 1861117556
at the page below you can see how it must done the cylinder looks the same as the mutt cylinder it sits at the end of the page

https://www.hometownbuick.com/1957-buic ... nt-repair/

at the mutt you must adjust the puschrod to know if the compensation hole is open see drawing
the puschrod must hang free with a litle play
if the adjusting is wrong after several brakes your brakes get dragging
to put brakes cylinders together use brake grease see below or brake fluid

https://www.ebay.com/itm/180G-ATE-Brake ... 100623.m-1

george

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muttguru
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Re: Broken brake cylinder?

Unread post by muttguru » May 14th, 2020, 6:27 am

Rupert.....

If you buy a master cylinder repair kit, MAKE CERTAIN that the "reed valve" is IDENTICAL to the old one. Our member Horst posted the details in the G838 Wiki..... some of the repair kits contain the WRONG reed valve.

And here's a link to the re-assembly of the M/C for you:-

http://forums.g503.com/viewtopic.php?t=289691


Rick.....Horst's warning...it used to be in the Wiki...... but the Wiki has disappeared from the board. Anyone still got a copy?

Ken
Kind regards....
Ken

Always wanted - Details and pictures of M416 Trailer data plates & M151 data plates & body-tags for my research. Thanks!

Contact address - - muttguru@aol.com

Note for 2023..... Ken..."Less Stress - More Exercise!"

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rickf
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Re: Broken brake cylinder?

Unread post by rickf » May 14th, 2020, 8:40 am

I have a new wiki up on the board but personally I have no idea how to set it up. With all the other things I have been doing that has taken a back seat. I do still have the info from the old wiki thanks to Surveyor.
1964 M151A1
1984 M1008
1967 M416
04/1952 M100
12/1952 M100- Departed
AN/TSQ-114A Trailblazer- Gone

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rickf
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Re: Broken brake cylinder?

Unread post by rickf » May 14th, 2020, 8:42 am

Ken, I looked through those old files and the only thing in the brake section is a warning about using the kit for an MB which looks similar.

repair kit for master cylinder
make sure when getting a master cylinder repair kit that it contains the correct size of the piston, compare the length of the old piston with the new piston. A repair kit for a MB Jeep does look similar but has a slightly longer piston. The wrong piston will install without any problems, it will brake but it will not release the brake pressure properly when getting off the pedal.
1964 M151A1
1984 M1008
1967 M416
04/1952 M100
12/1952 M100- Departed
AN/TSQ-114A Trailblazer- Gone

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Re: Broken brake cylinder?

Unread post by Surveyor » May 14th, 2020, 10:02 am

1960 M151 Run #1
"There is one nut on a M151 that is very difficult to remove....." - K8icu
"She ain't a Cadillac and she ain't a Rolls, But there ain't nothin' wrong with the radio" - Aaron Tippin
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rickf
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Re: Broken brake cylinder?

Unread post by rickf » May 14th, 2020, 10:14 am

PM sent
1964 M151A1
1984 M1008
1967 M416
04/1952 M100
12/1952 M100- Departed
AN/TSQ-114A Trailblazer- Gone

rupert's
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Re: Broken brake cylinder?

Unread post by rupert's » May 15th, 2020, 5:16 pm

I will not be complicated by such a small difference, also the piston is sunk and without sale.
I will buy a new one! Thanks for your advice! a greeting

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