# Old Jeep Brake System Repair



## Colonel Monk (Feb 12, 2014)

Howdy:

My old man, accidentally put the wrong brake fluid in our plow truck, the 1979 Jeep Cherokee. Brake do not work at all, the guy at autoparts store said that it likely ruined all the rubber seals in the entire brake system.

This vehicle does not drive on the road. Consider it, like a lawn tractor or something. I can plow without brakes as I did all last winter, but there were a few hard hits and I want to avoid breaking the plow.

This is probably our last season before the "creep" goes to the junkyard and gets replaced.

So, we are looking to spend the bare minimum to restore SOME brake function.

I want to plug the rear port of the master cylinder going to the rear brakes, to avoid wasting money on new rear brake lines, wheel cylinders, etc. Rear lines, if not already rusted out, are damn close.

So, strictly speaking, what is the easiest method to accomplish this? I know that brake lines are "double flared", so the seal is on the tubing flare itself, right? Would crushing a short length of tubing and welding shut work?

Thanks for the help

CM

PS Please don't lecture me on the safety of what I'm doing. This vehicle has not touched pavement since 1993, and it never will, till we haul it to the junk yard. I just need a tiny bit of brake power to slow down in our completely flat driveway and soften the snowbank hits. I would never do this on a vehicle that would be driven on public roadways.


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## dieselss (Jan 3, 2008)

Get a section of brake line, and get a cap for the other end, for blocking off the rear line. The fronts, thats ruff. Your still gunna need a new master cylinder, front flex lines and calipers. And a full fluid flush. Take what you will from my list, but that's what I'd be suggesting as a permanent fix


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## Colonel Monk (Feb 12, 2014)

dieselss;1842056 said:


> Get a section of brake line, and get a cap for the other end, for blocking off the rear line. The fronts, thats ruff. Your still gunna need a new master cylinder, front flex lines and calipers. And a full fluid flush. Take what you will from my list, but that's what I'd be suggesting as a permanent fix


Yeah, I didn't mention that, but was planning on calipers, mastercyl, and I guess hoses.

As far as a cap, is there such a thing that holds pressure? Been looking but haven't found one.

Thx


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## dieselss (Jan 3, 2008)

Yea they make "caps" that fit brake lines. Should be hard to find them


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## jhenderson9196 (Nov 14, 2010)

Plug the port in the master directly. What type of fluid got in by mistake? Maybe just a flush?


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## Colonel Monk (Feb 12, 2014)

Howdy

I found AN Flare Plugs at jegs.com - all I need to do is figure out what size AN fitting it is, and I can plug the rear port in the master cylinder directly.

I believe the Brake Fluid used, was DOT 5 which is silicone based. What I've read doesn't say that you can't use it, but if used in a DOT 3 or 4 system without flushing, will cause brake failure, which is where I'm at.

By not fixing the rear brakes and the super rusty rear brake line, I'm probably saving at least $100. Couldn't sell this vehicle without the plow for more than $100 if that, so that's why I'm being so stingy.

Anyone have an idea about flushing the lines? I was going to check that out next.

CM


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## Colonel Monk (Feb 12, 2014)

Says that denatured alcohol is the right solvent for a flush.

O'Reilly has some pretty amazingly cheap prices for calipers/master cyl, looks like $25 each and $20 each for hoses. That ought to fix it up so I can at least stop. Hoping that the front line isn't rusted out, that appears to be more difficult and costly to fix, and nobody has OEM already bent lines.

Hmmm. Are we sure it needs hoses? If they don't leak they should be OK? The mixing of the DOT 3/5 ruins seals which causes the brake failure, but hoses?

Not sure.

CM


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## dieselss (Jan 3, 2008)

The hoses are double walled rubber. If it ruins seals, it ruins rubber. Don't put alcohol in the system, just flush with dot3
No one has or carries oem lines, except in stainless. Prebent lines....ha


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## novawagonmaster (Jun 16, 2014)

It would be cheaper to get the rears working and block off the front.
Master cylinder, one rear flex hose, and two wheel cylinders.


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## dieselss (Jan 3, 2008)

True, but with weight transfer, they would lock up almost all the time


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## Whiffyspark (Dec 23, 2009)

dieselss;1842449 said:


> The hoses are double walled rubber. If it ruins seals, it ruins rubber. Don't put alcohol in the system, just flush with dot3
> No one has or carries oem lines, except in stainless. Prebent lines....ha


Yup. They may look fine but chances are they aren't.


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## kimber750 (Sep 19, 2011)

I don't get it. You are willing to spend all the money to get the front brakes working but not the $20-30 to get the rear working also? I don't care if you only move it a few feet a year, you should repair the brakes properly. I can only hope there is no one anywhere near you while you are operating that jeep. 

Spend the little bit extra and fix them all.


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## Colonel Monk (Feb 12, 2014)

kimber750;1842484 said:


> I don't get it. You are willing to spend all the money to get the front brakes working but not the $20-30 to get the rear working also? I don't care if you only move it a few feet a year, you should repair the brakes properly. I can only hope there is no one anywhere near you while you are operating that jeep.
> 
> Spend the little bit extra and fix them all.


Either you didn't read my entire first post, or you just want to stir the pot.

I'm OK with you not getting it, but perhaps you could try and think that other's needs might be different from your own.

I can't even really afford to fix the brakes just now, let alone the added expense and hassle of fixing the rear brakes on a vehicle that hasn't been licensed since 1993, and which is headed to the junk yard just as soon as I can afford to replace it.

I think your perceived danger of not having rear brakes, is laughable. As I said, I plowed the entire last season on our dead flat, swamp dirt driveway with no brakes and aside of a few hard snowbanks it was a non-issue.

If you are a pro-plower, you probably have a different idea of what plowing is than I do. I am slow and deliberate, and work with what I have. I plow in 4LO, and never leave my property. In contrast, you are probably on hilly terrain, on pavement, on other people's property, and trying to make dollar to hustle is necessary. That's not my plowing world, hoss.

There is no way I can fix the rears for $20-30 bucks. It's probably another $60 minimum in parts, and that's if the brake line is sound. It sure doesn't look like it, the chassis in the rear is perforated - that's why I'm telling you, this vehicle is going to the junk yard, it is THRU!

I'm out of work, I cannot afford to spend the extra money right now. If I had any money at all, I'd be replacing the vehicle.


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## kimber750 (Sep 19, 2011)

Colonel Monk;1842539 said:


> Either you didn't read my entire first post, or you just want to stir the pot.
> 
> I'm OK with you not getting it, but perhaps you could try and think that other's needs might be different from your own.
> 
> ...


You live in Kalamazoo? Maybe it would be best if you scrap the vehicle.. If you can't fix it right don't bother. I read your original post. Just because you don't want to hear how stupid your idea is doesn't mean you are not gonna to hear about. You also said you had a few hard hits, what happened there? Wouldn't have been nice to have a vehicle that can stop?

So call it stirring the pot or whatever, what you are attempting to do is stupid. Fix it or scrap it.


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## Colonel Monk (Feb 12, 2014)

kimber750;1842547 said:


> You live in Kalamazoo? Maybe it would be best if you scrap the vehicle.. If you can't fix it right don't bother. I read your original post. Just because you don't want to hear how stupid your idea is doesn't mean you are not gonna to hear about. You also said you had a few hard hits, what happened there? Wouldn't have been nice to have a vehicle that can stop?
> 
> So call it stirring the pot or whatever, what you are attempting to do is stupid. Fix it or scrap it.


OK, whatever you say, grand high poohbah of fixing things right. 

Sure, my idea is stupid. Saving money that I do not have is stupid. Restoring some brake function to my sorry-a** plow vehicle is stupid.

So far, you're the only one of the responses that feels the need to lecture me on my choice of repair, because you can't see that this is not a highway vehicle, and therefore doesn't need the stopping power of a highway vehicle.

These others have been helpful and seem to understand, and that I have little money at the moment, and don't want to spend it on replacing the brakes of a plow truck that is headed for the junk pile. They understand that this is not some commercial plow vehicle where the suggested repair would in fact, be unthinkable.

I suppose you think I should overhaul the engine that still runs, replace the worn clutch and throwout bearing that still works but squeaks, replace the tire with the split cord (but that performs fine at plowing speed), patch and repaint the body, and every other thing that is wrong with this 35 year old vehicle too, right?

My momma always said, if you can't say something nice, don't say it at all. Perhaps you're some kind of expert plow driver, but this community and this member doesn't need your negative comments.


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## Colonel Monk (Feb 12, 2014)

dieselss, thanks for the comments. Yeah, I believe you're right, and that's why I'm fixing the fronts - not to mention, that the rear of this thing is in terrible shape. I sincerely doubt that I could get the rear wheel cylinders off without fracturing one of these rusty lines - that and, the last time we worked on the brakes (probably 25 years ago) we had a tough time getting the drums off, and everything inside was rusty too. brake adjusters and all that were pretty sorry. Just don't want to even mess with them. The fronts, even if the steel line needs replacing will be a lot easier and cheaper both in terms of time and money.

One more season and the old Creep is going to the great plowtruck graveyard in the sky.

CM


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## kimber750 (Sep 19, 2011)

Colonel Monk;1842583 said:


> My momma always said, if you can't say something nice, don't say it at all. Perhaps you're some kind of expert plow driver, but this community and this member doesn't need your negative comments.


You are the one making assumptions about me. Your idea for a fix is stupid, plain and simple. You came here for advice, take the good with the bad. The only reason you hate my opinion is because you know it is true. If you are so worried about cost go dig up some used parts. Or flush the system and see what actually needs fixed instead of just throwing a pile of parts at it.

What is gonna happen when you block one port on the master? There is only one piston to operate both front and rear. Rock hard pedal since the fluid on side has no where to go? If it does work what about portioning valve? If these seals are gone fluid is just going to leak out.

And yes I consider myself a professional plow driver and a proper mechanic.


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## jhenderson9196 (Nov 14, 2010)

Kimber should also consider himself an idiot. An empty reservoir contains air, which is compresable. No hard pedal. It's also obvious you've never run a farm or estate vehicle. When I'm on my own property the safety of the operation is my business, no one else's. I don't need you or anyone like you to look after me. Neither does the O.P. Try and find something you know about and comment on that.


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## kimber750 (Sep 19, 2011)

jhenderson9196;1843547 said:


> Kimber should also consider himself an idiot. An empty reservoir contains air, which is compresable. No hard pedal. It's also obvious you've never run a farm or estate vehicle. When I'm on my own property the safety of the operation is my business, no one else's. I don't need you or anyone like you to look after me. Neither does the O.P. Try and find something you know about and comment on that.


First I never called him an idiot, try not to stoop to the name calling. I said it was stupid to plow with no brakes and it is stupid to only fix it part way.

What is making you assume it has separate reservoirs? He made it everyone's business when here came to a public forum. Also i could care less what you do on a farm or estate but I can assure you all of my farm equipment including a 1946 Ferguson TO20 has brakes.

Now the OP is plowing his driveway with a vehicle with no brakes, in my part of the world all the driveways lead to a public street. So what happens when he coasts just a little too far at the wrong moment?

But I appreciate your opinion.


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## BIG NICKY (Aug 17, 2014)

Just disconnect the line that goes into the master for the rear brakes. cut of the end and take it to napa and just tell them you need the cap. they will match the threads up to the one brought in. when you go to install the plug make sure you put some Teflon tape to seal the threads, since there wont be a flare on the cap. just get the cheap hoses and if need be get some bulk 3/16 steel line and rent the double flaring tool from auto clown or orielys since in the end the tool is free once you return it. and like diesless said just flush it with some dot 3.


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## jhenderson9196 (Nov 14, 2010)

No , I called YOU an idiot. You consider yourself a proper mechanic but don't know the first thing about brake systems.It's a 1979 jeep. Dual brake systems have been the law sense 1967. It has 2 separate reservoirs. Do you think it might be in everyones interest if he had some brakes instead of none at all? It's usually better if you know what you are talking about before you post. He asked a technical question and deserved the right answer, not your opinion on morality. You think you know what's best for everybody, but don't even know the basics about the posed question. Next time try to have something informed to say or say nothing at all.


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## Whiffyspark (Dec 23, 2009)

Dual brake system doesn't mean seperate reservoirs. Even if they are they are still connected. 

Kimber is right on every account, but I'm sure he'll be fine just capping the line and running fronts


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## jhenderson9196 (Nov 14, 2010)

The whole idea of dual systems is you can't loose all the fluid. Look in the master, you'll see the separation part way down the reservoir. You are Both wrong.


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## Whiffyspark (Dec 23, 2009)

It doesn't work like you think it does. When you blow a brake line why do you lose the pedal?


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## kimber750 (Sep 19, 2011)

jhenderson9196;1843940 said:


> No , I called YOU an idiot. You consider yourself a proper mechanic but don't know the first thing about brake systems.It's a 1979 jeep. Dual brake systems have been the law sense 1967. It has 2 separate reservoirs. Do you think it might be in everyones interest if he had some brakes instead of none at all? It's usually better if you know what you are talking about before you post. He asked a technical question and deserved the right answer, not your opinion on morality. You think you know what's best for everybody, but don't even know the basics about the posed question. Next time try to have something informed to say or say nothing at all.


You can call me whatever you like. I will test your theory since I just happen to have a 79 Jeep master cylinder laying around. You condoning the jerry rigging a brake system just shows you have no concern about yourself or the people around you. So get mad, spew insults and whatever makes it easier for you. No proper mechanic would ever consider doing this to a vehicle.

Also if you go back to my post that got you so infuriated you will see they were "what if" comments meaning since I have never attempted anything like this I have no idea what will happen.

Again, to the OP. I suggest flushing the system and see what works and what doesn't. You may be surprised by how few parts you need to correct your brakes. And when I am done testing Jeffery's theory you are more than welcome to the master cylinder since I removed it to convert to wrangler power brake system. I may even have other parts now that I know what vehicle you are attempting to repair.


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## 32vld (Feb 4, 2011)

Because something that is not right but still can be done does not make it right to do it.

Even on private property there is still the risk to damage and personal injury.
As pointed out near the end of driveway and the jeep winds up in the road.

Accident, dent someone's car at the least, death at the worst. Not to mention the civil liability. How you going to pay a law suit when you appear to not be able to pay for parts to fix the brakes?

Flush out system.
Buy two wheel cylinder kits for the rear, two caliper kits for the front, master cylinder kit, three brake hoses.
Then remove the old parts and install the new parts.
Bleed the system.
Good to go.


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## jhenderson9196 (Nov 14, 2010)

The pedal sags. But if the system is in good repair the pedal does not go to the floor. It feels weak because you are using all the available leverage and possibly power booster on 1/2 the system. As for Kimber, go get your master, I'll wait. Chances are good that on a 79, jeep went so far as to put 2 caps on the reservoir. As for 32, you don't know the specifics. You assume a great deal. Maybe you should worry about your own situation instead of sticking your nose in his. If he's comfortable doing this it's none of your business. He didn't ask for your moral or legal opinion. He asked how to plug a brake line. I'm sure you know what's best for me when it comes to my taxes or medical coverage but sense I haven't asked for your opinion I don't expect you to expound on them. He didn't either.


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## kimber750 (Sep 19, 2011)

jhenderson9196;1844033 said:


> The pedal sags. But if the system is in good repair the pedal does not go to the floor. It feels weak because you are using all the available leverage and possibly power booster on 1/2 the system. As for Kimber, go get your master, I'll wait. Chances are good that on a 79, jeep went so far as to put 2 caps on the reservoir. As for 32, you don't know the specifics. You assume a great deal. Maybe you should worry about your own situation instead of sticking your nose in his. If he's comfortable doing this it's none of your business. He didn't ask for your moral or legal opinion. He asked how to plug a brake line. I'm sure you know what's best for me when it comes to my taxes or medical coverage but sense I haven't asked for your opinion I don't expect you to expound on them. He didn't either.


One cap but two different reservoirs. No openings between the two. So how would you like me to test it. Connect just the front brake line, fill only that part of the reservoir and plug rear port? Or even easier, just plug both ports and test with no fluid?


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## jhenderson9196 (Nov 14, 2010)

If you fill the front and plug the rear, the pedal will compress the air in the empty compartment and push the fluid in the other. Just as it was designed to do.


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