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Aftermarket portioning valve


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Hi guys, so I can’t seem to get this brake thing under control. The original system is bi passed with all new lines going to both back axles and front axles. The portioning valve I’m guessing is a TJ one I think. Heck idk. Lol. Got in the truck and pedal went to the floor. Popped the hood and fluid is coming from around one of the fittings I think. My question is does anyone have a good recommendation for an aftermarket portioning valve. I’m really at my wits end with these damn brakes. Thanks guys. 

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Disk front drum back? The stock MJ system has unconventional to say the least. So we need to know what you currently have in the truck. Especially the distribution block below the master cylinder. Can you take some pictures of your brake components? Master/booster, existing prop valve, existing distribution block, and rear axle line where the old load sensing valve use to be

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3 hours ago, Whitaker717 said:

Absolutely. I will tomorrow before it gets towed. Lol. I believe it’s just a TJ portioning valve. It is definitely frustrating. It makes me want to give up. 


So the original MJ system didn’t have an actual prop valve up front. It had a distribution block full allowed full pressure to all lines. The rear line then went to the load sensing valve at the rear axle. This valve offers proportioning of brake pressure so the back doesn’t lock up before the front. 
 

It’s pretty common to delete the rear valve. If you have a TJ proportioning valve it should work fine. If it’s leaking, it may just need the line re-flared. The prop valve itself rarely fails.

 

Keep in mind though that you never want to let the master cylinder run empty when you work on the brake lines or you’ll introduce air into the system. 

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This three pictures of the rear are where they're supposed to be. Where they both connect should then go up to the rear proportioning valve unless deleted. That's the photo that's needed.

I agree with just getting a stock or Wilwood valve for the front if that's your issue, but I don't see fluid in the photos. Where is it coming from exactly? Brake fluid doesn't really evaporate so it'll stick around where it's leaking from. Maybe get someone to hit the brakes so you can get a look.

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48 minutes ago, MiNi Beast said:

Try putting a flare wrench on it and tightening it abit. :dunno:


Agreed, this should be a simple fix. Leave that prop valve alone and try tightening the fittings first. If that doesn’t work you may need to replace the fittings and re flare the line. You have the newer style copper nickel line which is fairly easy to flare properly. Once the leak is fixed you will likely have to bleed the whole system. just make sure the master cylinder never goes dry. If it does you will need to bleed the master first.

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Thanks guy quick follow up question, once I got the truck back when the brakes got completed I pushed down the emergency brake. That’s why my das light was on. Well being novice I couldn’t figure out why it stayed on. I drove it around for a couple weeks with the light on because it didn’t feel any different. I finally took off the the rear tire and discovered the brake was stuck and had been wearing. Still looks like I have life in the shoes. I released it and put everything back together and somewhat re adjusted the drums. My question is could that have caused the fittings to leak? Would it have created a lot of back pressure by dragging the rear drums. Just curious to see if this was my screw up, which it kinda was. 

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    I have a hydraulic brake flaring tool I use at work and once in a while I get bad flares. If you are using a hand flaring tool the chances are greater of bad flares. 
     How much petal travel do you have? A inch or two or half a petal. 

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Assuming all air is out when I adjust rear brakes I like the rear wheel to turn 1/2 to 3/4 of a turn before it stops when you spin it.  About 2 in petal travel is not horrible as long as it’s not halfway then you should be fine.

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On 9/30/2021 at 6:57 PM, Whitaker717 said:

My stock components are all gone. Someone before me eliminated the rear thing. So now I have all new lines run individually to each caliper and drum. Just need to find a reliable portion valve. The one I have is brand new and now leaking. Idk man. 

 

Wait -- individual lines to each REAR wheel? That's definitely NOT right.

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