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View Full Version : Brakes!!! Have a few questions


RedCreeper
07-01-2010, 11:38 PM
As I know this is not a toyota but the basics should all be the same. After cutting a brake line on the Fathers Day run i got under it and started to takethe parts off so i know what to get or have made. I noticed that the passenger side was set up different than the driver. To start the way it is plumbed does not seem right. from the frame the hard line goes to a braided line then to the axle where a T is and the driver side has a 28 in braided line to the caliper and the passenger side has a small hard line from the T and then a Braided line to the caliper. Also the braided line on the passenger is a smaller diameter than the driver line. Shouldnt these be the same? shouldnt the left and right be plumbed the samehey work even? I was going to get 2 lines the same and get rid of the small hard line from the T and make them the same diameter. is this correct thinking? I have spongy brakes now and have bled them several times and thinking this may cause it. or at least the larger line to one side. Doesnt smaller line have more pressure? Any help or ideas would be great. Also since i lost all the fluid to one side of the master do i need to bench bleed it again or am i ok to just plumb it again and bleed it? I am surprised i am able to stop at all. thanks again in advance.

Kenny

RedCreeper
07-01-2010, 11:54 PM
almost forgot that it has discs in the rear and the master is a 2 chamber and a prop valve splitting duty. Also i noticed the front lines are larger also but they are the same on both sides. some folks opinion say i need to put a junction block on it like the original jeeps do so if i do cut a line i will be able to stop and get it home. is this possible or something that can be done? is this a better way to run the system?

corsair23
07-02-2010, 10:27 AM
I'm a brake noob and until a couple years ago hadn't even replaced pads or bled brakes before so all I can offer you is a BUMP to the top :)

rover67
07-02-2010, 10:47 AM
The different size braided lines shouldn't be causeing a problem assuming they are both rated for brake line use. Also, the hard line going from the Tee to one side is normal..

RedCreeper
07-02-2010, 11:31 AM
Thanks gang. Marco, would it hurt to get rid of the hard line used as a splice? Looks hokie. Was going to take the braided line from the caliper directly to the t.

rover67
07-02-2010, 12:56 PM
Thanks gang. Marco, would it hurt to get rid of the hard line used as a splice? Looks hokie. Was going to take the braided line from the caliper directly to the t.

It probably wouldn't hurt, I like to keep the flexible sections short though, it minimizes the amount of line that can flex under pressure. most of the time brake systems have as much hard line as possible with only short flex sections for parts that need them.

RedCreeper
07-02-2010, 03:17 PM
Thanks Marco, just got back and have new banjos, fittings and a new line for the passenger side to make it simple. I like to keep as much hard line as possible but this looked hokie as i said. so just got a braided line to match it. i can keep the old piece for a spare part if that side ends up breaking. I also seen that the front lines from the caliper are larger also. Depending on the outcome i may change those to the smaller one for better clamping force. we shall see how all this works out.

Steve
07-03-2010, 06:48 AM
Kenny,
Don't waste your money on different hoses for the front. The outside diameter of the hose is not an indicator of its ability to supply "clamping force". You only need to replace them if they are split/damaged/kinked/leaking etc..

The ID of the hose will determine the amount of fluid the hose will flow. I doubt that the different size hoses would flow such a substantially different amount that you could notice anything from side to side or front to rear.

Smaller ID of the hose will NOT increase the pressure at the caliper.

A smaller bore master cylinder will increase the pressure at the slave/caliper/wheel cylinder, compared to a larger bore master at the expense of volume of fluid displaced.

If your brakes are still "spongy", there is still air in the system somewhere.
HTH,
Steve

RedCreeper
07-06-2010, 09:29 PM
Kenny,
Don't waste your money on different hoses for the front. The outside diameter of the hose is not an indicator of its ability to supply "clamping force". You only need to replace them if they are split/damaged/kinked/leaking etc..

The ID of the hose will determine the amount of fluid the hose will flow. I doubt that the different size hoses would flow such a substantially different amount that you could notice anything from side to side or front to rear.

Smaller ID of the hose will NOT increase the pressure at the caliper.

A smaller bore master cylinder will increase the pressure at the slave/caliper/wheel cylinder, compared to a larger bore master at the expense of volume of fluid displaced.

If your brakes are still "spongy", there is still air in the system somewhere.
HTH,
Steve


Thanks Steve, got it together this past weekend. At least it does not look hokie anymore. I got it out tonight and still spongy. Do i need to bench bleed the master? Any one north have a power bleeder and some time? Maybe that will work. I got speed bleeders and is a nice item but dont think it worked as well as i had heard or hoped. Next step.....

Find a power bleeder and try that. Unless i need to bench bleed it.

Kenny

farnhamstj
07-07-2010, 09:36 AM
I know what's wrong....




Sorry Kenny, I can't help myself.

Air Randy
07-07-2010, 12:56 PM
Why don't you make arrangements to bring this thing down to my place one of these days? Steve only lives a few miles away and we could get together to check it out. I'm sure we can de-bug it rather quickly that way. Doing it all by email and post is the long, slow way.

RedCreeper
07-07-2010, 01:15 PM
Randy,

I think i will take you up on the offer. Just need to see when your not out playing and i am home or have time. Most likely after Camp Hale run. I have family in town this weekend so that is out. Let me know what your time looks like. email or PM is fine. thanks.

Kenny

Air Randy
07-07-2010, 03:31 PM
I'm helping Tom this weekend, next weekend is Camp Hale, weekend after that is the 40's only run, weekend after that is the Rally & trail run, so it could be a while

RedCreeper
07-08-2010, 01:16 PM
I understand. Just keep me informed. I can't those times anyway so that works out. Was looking at near the end of aug. just let me know. thanks randy.

Steve
07-08-2010, 04:30 PM
Why don't you make arrangements to bring this thing down to my place one of these days? Steve only lives a few miles away and we could get together to check it out. I'm sure we can de-bug it rather quickly that way. Doing it all by email and post is the long, slow way.

Let me know what you guys work out and I will lend a helping hand. I do have a pressure bleeder and some master cylinder adapters and we can try that approach.
Later,
Steve

Air Randy
07-08-2010, 07:45 PM
He has a "Navajo brake system" on this thing. It apparently upgrades you to a dual diaphragm booster and a smaller diameter master cylinder to boost braking power. I suspect the MC was never bled right so using your power bleeder may be the ticket.

RedCreeper
07-09-2010, 02:17 PM
I am thinking the same.... or hoping....

RedCreeper
07-27-2010, 09:12 AM
Been thinking of this in my sleep. pretty bad. Randy or Steve do you think it may be the front brakes? i have not bled them since all this happend. Could this cause all these problems if one is good and air in the other?

Air Randy
07-27-2010, 09:33 AM
It's possible, only way to know for sure is to bleed everything out properly then see if it works OK.

I'm going on the FJ40 run this Saturday but if Steve is available on Sunday we could take a look at it then. We can work on it at my place, or if Steve doesn't want to drag his brake bleeder stuff over here, we can drive 8 miles further East to his place.

FJBRADY
07-27-2010, 09:38 AM
Been thinking of this in my sleep. pretty bad. Randy or Steve do you think it may be the front brakes? i have not bled them since all this happend. Could this cause all these problems if one is good and air in the other?

Or you can take it to a local brake place today and get some sleep tonight. :hill:

RedCreeper
07-27-2010, 09:43 AM
Thanks Steve, dont get paid till friday. And I have trust issues with just the local brake guy on a custom brake system. Not stock at least. But i know it is all the same.

Randy, let me bleed the front tonight and see and i will let you know about sunday. Would be a good test to trailer it there also. just got the tranny done on the truck and hope that fixes my problem. I will let you know.

RedCreeper
07-28-2010, 10:07 PM
Well i tried to bleed the front and only was able to get one side till the bleeder broke on the other side. I give up. I am doomed. Looks like if everyone can do sunday that would work best. just need to get all the yard stuff done on saturday. Randy just let me know if that is ok with you guys. thanks in advance.

Air Randy
07-29-2010, 09:04 AM
Did you get any air out of the side you were able to bleed? Do you have the stuff to tap out the broken bleeder and replace it?

RedCreeper
07-29-2010, 09:07 AM
I did not see any. I have bolt extractors and will go to NAPA to see if i can get another bleeder tomorrow. I just dont know the size or the app yet. I have a set of speed bleeders that did not work on the rear and can try those. waiting on the PO to get that info. So if all goes right i will get it out and have a new one in. I will definatly need to bleed them then.

Steve
07-29-2010, 05:28 PM
I can help on Sunday. Just need to know where and what time.
LMK.
Randy, you have my #, give me a call.
Steve

corsair23
07-29-2010, 05:34 PM
Did you get any air out of the side you were able to bleed?

I did not see any.

Just had to put these two posts together for a good :lmao:at Kenny's expense...Sorry Kenny, but that there is funny stuff :D

RedCreeper
07-29-2010, 10:00 PM
OK let me correct then....

it came gushing out and did not spit or sputter the fluid when i cracked the line.

Better. |o)

Why is evrybudy pickin on me.....

Dr. Schlegs
07-29-2010, 10:07 PM
I haven't picked on you. I'm too busy picking on Francis.

RedCreeper
07-29-2010, 10:34 PM
Thanks Doc. Yet, i know its coming.... lol

Francis?

Air Randy
07-30-2010, 08:45 AM
Steve's available on Sunday, you need to confirm if you're going to bring it down and at what time. If we don't do it this Sunday I know it will be at least 3 weeks before my schedule is open again.

RedCreeper
07-30-2010, 10:05 PM
Randy,

Yeah i am still bringing it. I hope to have the bleeder in or at least the one i have i hope it fits. I am beat now but if i get a burst of energy i will try tonight. I would like to do it first thing if you guys can. It is about a hour 15 or so to your place so i would shoot for 9 or 10. Just let me know what works and what i need to bring. Thanks in advance guys.

RedCreeper
07-30-2010, 10:07 PM
Sorry for the late reply. i took the day off and have been messing with 4 tons of rock. One piece at a time in the truck i put 2 tons in there. Man i am beat.