Master cylinder help

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mallard
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Master cylinder help

Unread post by mallard » September 26th, 2014, 10:56 pm

I'm in the process of pulling the pedal assembly on my jeep to change the master cylinder and change the brake pedal spring and bushings. After I unhooked the brake line , clutch linkage and the 6 bolts holding it up I noticed the 2 big wires for the starter switch are run through the holes in the pedal assembly. So now I've got to take them off to get it out. Is this the correct way they should have been run or did the previous owner put them back wrong. Also all of the dash wires are run below the pedal assembly. Does anybody have a picture of under the dash of how the wires should be run so I can put them back in the correct place. Or does somebody mind busting a few ribs and taking a picture? Thanks for all the help.
1965 M151A1

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rickf
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Re: Master cylinder help

Unread post by rickf » September 27th, 2014, 9:18 am

Make SURE you take the ground wire off before fooling with those battery cables. The main wiring harness should go above the pedals with maybe the brake light wires and turn signal wires snaking through. The battery cable wires I do not remember, I don't remember having to play with them on mine.
1964 M151A1
1984 M1008
1967 M416
04/1952 M100
12/1952 M100- Departed
AN/TSQ-114A Trailblazer- Gone

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Horst
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Re: Master cylinder help

Unread post by Horst » September 27th, 2014, 12:40 pm

my 151 is already in storage so I unfortunately cannot take a picture for you. But sure remember that removing the pedal cluster did not involve touching the cables at all.
Horst

1972 USMC M151A2 w/ROPS (ex Barstow) and M416
1962 M201 and trailer
1966 GTO,1982 E350 Skoolie, 1987 SJ413, 1987 911
Gone: 2xM35A2c, Unimog 404S, Hanomag AL28, DKW Munga

Fil Bonica
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Re: Master cylinder help

Unread post by Fil Bonica » September 27th, 2014, 2:52 pm

It is my recollection that the cables should be dressed above the brake clutch assembly.
This is what we did when we assembled myMutt two years ago.
It is a little more troublesome then but it avoids what you are going through now.
Remove things as they are now and reroute them as you are done. The cables can go above the brackets so they are t in the way.

Good luck the whole project is one of the most fun!!! In an 151.
Only worse is the heater.

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Re: Master cylinder help

Unread post by old dodge guy » September 27th, 2014, 3:40 pm

I just went out and looked at my A2, the cables are the starter cables and go UNDER and behind the brake brackets. There should be a small space behind the bracket for them to run in. This would be along the firewall at the back of the brake bracket.
I'll try to post photos later, headed to a car show in just a bit, so no time to download from the camera. :D I'd linger and send them now, but since I'm in charge, gotta go! They yell at me when I'm late :lol:
Still crazy after all these years.
The OD bug bit me in 1970......and I have never been the same

mallard
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Re: Master cylinder help

Unread post by mallard » September 27th, 2014, 9:13 pm

Thanks for the help, I've gotten in the habit of just taking the batteries out and putting them on a trickle charger to top them off. They caint bite me that way. I got the pedal assy out so now time to clean everything up. Now time to tape up a few cracking wires and zip tie some together. Have fun at the car show and look forward to the pictures so I can put it back together correctly
1965 M151A1

csmith
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Re: Master cylinder help

Unread post by csmith » September 28th, 2014, 9:51 pm

Not necessary to remove the peddle assembly to replace the MC. A few threads on the site pertaining to same. But you got it all out now so good time to clean and rework it all.
1976 M151A2 4 Color Cammo Mutt, aquired August 09
1976 or 7? M151A2 "Miss Sandy" Driver, aquired May 2010
Former owner M151A2 "Miss Saigon" Vietnam Rescue Sold Sept 09
Fond appreciation for the M151 Breed!!

mallard
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Re: Master cylinder help

Unread post by mallard » September 29th, 2014, 8:49 pm

Well I got the new brake line in tonight since it broke when I was taking it loose from the mc, I wish I would have done this before putting the motor in.

It would still be helpful for a picture of the starter switch wire routing if anybody has time. I looked at the back of the pedal assy and didn't see any where for it to run behind. Thanks and have a good evening
1965 M151A1

Hambone
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Re: Master cylinder help

Unread post by Hambone » September 29th, 2014, 10:14 pm

Mine runs behind the pedal assembly and held on by clamp on firewall.
Image
Image

Hope this helps took pics in the dark.

mallard
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Re: Master cylinder help

Unread post by mallard » September 29th, 2014, 11:24 pm

Thanks hambone, that clears it up, I'm going to try to get it all put back together tomorrow evening
1965 M151A1

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Re: Master cylinder help

Unread post by old dodge guy » September 30th, 2014, 10:22 pm

OK, finally found my round 2 it. Ecch, what a week it has been. :shock: Apologies on being late, taking someone to ER kinda ruins yer week, but all will be well.
Here are some more photos, hope it will still help.
Image
Image
Image
Image
Go the the album for more photos and larger view.
edit..
You can also use the Ctrl key on the keyboard and the mouse scroll button to enlarge or decrease the photo size.
Still crazy after all these years.
The OD bug bit me in 1970......and I have never been the same

mallard
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Re: Master cylinder help

Unread post by mallard » October 2nd, 2014, 9:39 pm

Thank you both for the pictures they helped a lot, I was able to get it all back put in, now on to the next problem. I think the front right rubber line is blocking flow so I should have a new one in first of next week.

Also if I press the brake pedal hard I get a drop or two of brake fluid on my boots, it appears to be coming out from around the brass washers that go on the big bolt in the bottom. I tightened it up what I thought was fairly tight but didn't want to break it. Any thoughts?
1965 M151A1

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Horst
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Re: Master cylinder help

Unread post by Horst » October 4th, 2014, 6:22 am

Does an A1 has the pressure switch for the brake lights? Not like the A2 which has a mechanical operated switch. Is that where it is coming from?

Not really helpful but honestly I had to post something to get to 1000 posts and wanted to see what rank I will get :)
Horst

1972 USMC M151A2 w/ROPS (ex Barstow) and M416
1962 M201 and trailer
1966 GTO,1982 E350 Skoolie, 1987 SJ413, 1987 911
Gone: 2xM35A2c, Unimog 404S, Hanomag AL28, DKW Munga

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Re: Master cylinder help

Unread post by rickf » October 4th, 2014, 8:38 am

Damn! Horst does actually have a sense of humor!!!!!

As far as the leak, there could be a piece of dirt on one of the washers or they could need to be replaced. If you take them to an older parts store, not a chain store like Auto zone, they should be able to match you up some mew washers. You could anneal the old ones by heating them up till the turn a blueish color and let them cool on there own. This will soften them up again and that may work. I usually tell people to try to get new ones first though because if you are not familiar with the annealing process it could go wrong and then you have nothing. I would just take them off and clean them and the surface first and try that. A hint to keep from losing to much fluid and making a mess, make a stick that will hold your brake pedal down just a hair past the free play. this will close the return port and the fluid will not gravity drain out while the line is off.
1964 M151A1
1984 M1008
1967 M416
04/1952 M100
12/1952 M100- Departed
AN/TSQ-114A Trailblazer- Gone

Fil Bonica
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Re: Master cylinder help

Unread post by Fil Bonica » October 4th, 2014, 9:59 am

Before you change the washers tighten the bolt a Little.
Make sure to hold the banjo fitting while you do it so it doesn't move.
Hope this helps.

Fil Bonica
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