working on replacing brake Master cylinder

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rickf
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Re: working on replacing brake Master cylinder

Post by rickf » April 16th, 2021, 5:25 pm

I will look again on Sunday, tomorrow is Range clean up day and I have to take my loader down there. I didn't even get it loaded today due to rain. Going to be hustling tomorrow! Where is the brake light switch mounted? As far as that little bracket all it is is a piece of angle iron, you could weld that to the new one instead of using that crusty pedal.
1964 M151A1
1984 M1008
1967 M416
04/1952 M100
12/1952 M100- Departed
AN/TSQ-114A Trailblazer- Gone

70mford151a2
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Re: working on replacing brake Master cylinder

Post by 70mford151a2 » April 16th, 2021, 8:34 pm

Rick yea but I don't have any way to weld it, but there is a welding shop in town maybe they could do it. that's what I'll do thanks Dave
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I'm sure you all have been waiting for this post

Post by 70mford151a2 » April 30th, 2021, 2:48 pm

well I have the brake pedal assembly re-assembled and I have but one question how in the hell do you get it back in and I thought taking it out was a bitch this time I have the rear bushing to deal with I didn't have it in the way taking it out and that was tough anyone knows of a video or anything to show how it's done.
why did I take this out why?!!! lol seriously if anyone has done this is there a trick or a secret maybe some black magic Thanks in advance
Dave Befuddled :shock: :shock: in Tennessee :? :?
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Re: working on replacing brake Master cylinder

Post by acudanut » April 30th, 2021, 3:47 pm

Brake lights ? Never worried about them lol. I use a red triangle led flashing light on the rear if I am on the road. It is common to take out the entire pedal assembly to replace the brake master cylinder. I also have added a additional spring (in the past) to help the brake pedal or clutch return home. I try to keep it simple. 2 people works wonders.

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Re: working on replacing brake Master cylinder

Post by m3a1 » April 30th, 2021, 5:00 pm

My recollection is, the only differences between taking it out and putting it back in was (1) it was a nice and clean and (2) gravity was working against me.

Consider putting it in with the firewall bolts loosely attached which will allow you some wriggle room while getting everything else lined up. You should be able to accomplish that with an original length fastener (if you are going with new hardware) but if you are working alone, a longer bolt might help you accomplish that (then swap it back out for an original length fastener).

Your clutch rod attachment thingy should be removed after the assembly is installed. Taking it off the assembly is what allows you to get the dog-leg (in the rod) onto the bit that attaches to the clutch pedal assembly. Then you can put it back on. Only Houdini could attach the clutch rod with everything assembled. As I recall, that's really the only trick to it..

Cheers,
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Re: working on replacing brake Master cylinder

Post by 70mford151a2 » April 30th, 2021, 5:24 pm

ok, I have it in and bolted down but there is an issue, and I don't understand what I did wrong anybody? ( see picture)
brakemasterissue.jpg
pi is sideways it is close to the left side looking at it
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Re: working on replacing brake Master cylinder

Post by 70mford151a2 » April 30th, 2021, 5:25 pm

everything went in straight all bolts lined up but I have this crap
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Re: working on replacing brake Master cylinder

Post by 70mford151a2 » May 1st, 2021, 9:59 am

"Brake lights? Never worry about them lol. I use a red triangle led flashing light on the rear if I am on the road. It is common to take out the entire pedal assembly to replace the brake master cylinder. I also have added an additional spring (in the past) to help the brake pedal or clutch return home. I try to keep it simple. 2 people works wonders."

I haven't gotten to the brake switch yet I'm still trying to figure out why the filler neck doesn't line up with the access hole in the body, I know it's going to be a problem when it comes to filling it and I can't get the rubber on I just can't see where I went wrong all the bolts lined up correctly and it's not loose but..........
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Re: working on replacing brake Master cylinder

Post by rickf » May 1st, 2021, 10:43 am

Does this master cylinder use the smaller 3/8 bolt holes or the original bigger holes? If it uses the bigger holes then loosen the bolts holding the master cylinder and see if it will move up a bit to line up with the hole and then tighten the bolts. Other than that it can only be be sheet metal damage that would cause the misalignment. You say you did not have the bolt and bushing on there before, is this what is causing the problem?
1964 M151A1
1984 M1008
1967 M416
04/1952 M100
12/1952 M100- Departed
AN/TSQ-114A Trailblazer- Gone

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Re: working on replacing brake Master cylinder

Post by 70mford151a2 » May 1st, 2021, 12:05 pm

thanks for responding it's not an up or down issue it's too far to the right by maybe 1/4 " I will never get the rubber part on or be able to unscrew the top with the rubber in the way here's a better pic ( I sent you a better pic PM) but here it is
brakemasterissue2.jpg
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Re: working on replacing brake Master cylinder

Post by Hambone » May 1st, 2021, 1:42 pm

Is it assembled correctly?, M/C should center up in bracket, compare your old M/C with the new one, is it machined correctly?
IMG_0919.JPG
IMG_0920.JPG
IMG_0921.JPG

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Re: working on replacing brake Master cylinder

Post by 70mford151a2 » May 1st, 2021, 2:54 pm

well I took it back out and it appears the brackets aren't the same well you know what they say if your gonna be dumb you got to be tough so I'll just use the old ones after a little R & R and maybe try and sell these down the road to someone with an A1. my own fault but what did I know? apparently not enough. :oops: :oops:
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Re: working on replacing brake Master cylinder

Post by 70mford151a2 » May 1st, 2021, 3:02 pm

the new brackets that I have, have risers where the bolts go pushing the M/C inward or over to the right compared to my old original brackets that don't seem to have them. I got new brackets because my old ones are a little rough but I am going to have to use them after cleanup and repaint.
Thanks for your help
Dave thinking it might be time to sell the old MUTT, don't want to but I can't keep up with it
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Re: working on replacing brake Master cylinder

Post by rickf » May 1st, 2021, 3:37 pm

Dave, I don't see how the master could fit in there if there was a boss pushing it over on one set but not the other but I looked up the numbers and they are different. The A1 does not use that end bolt and there is a bracket that goes with that bolt that I did not send you that I don't have. Moot point since the assembly itself is different. Send the assembly back and I will refund your money. I never knew there was a difference between the A2 and A1 pedal assemblies, live and learn.
1964 M151A1
1984 M1008
1967 M416
04/1952 M100
12/1952 M100- Departed
AN/TSQ-114A Trailblazer- Gone

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Re: working on replacing brake Master cylinder

Post by Mark » May 1st, 2021, 7:15 pm

[img]https://i.postimg.cc/ncR2BBSd/Mutt-Mast ... ap.png/img]Here's my brake cylinder cap, very hard to post this, before I could post multiple pics
mark


1968 m274A5
1960 m151
1981 m151A2
1964 m416
1971 m416

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