Booster upgrade questions

[tevans59]

Using a YJ booster mounted uside down the push rod rotates so it did not care , so does it matter?

Using stock manual MC the YJ one was ugly so would a new one make a difference?

Should I change out the proprotioning valve and if so why?

Already rebuit the rear brakes , new cylinders,shoes and drums turned and adjusted the rear brakes so they scraped a little.

She stops pretty good now with 35s but want lock then up but can I expect that anyway.

Just making sure I have not missed something that could make things better

 

[fzsk4p]

Using a YJ booster mounted uside down the push rod rotates so it did not care , so does it matter?

Using stock manual MC the YJ one was ugly so would a new one make a difference?

Should I change out the proprotioning valve and if so why?

Already rebuit the rear brakes , new cylinders,shoes and drums turned and adjusted the rear brakes so they scraped a little.

She stops pretty good now with 35s but want lock then up but can I expect that anyway.

Just making sure I have not missed something that could make things better

I have converted 2 CJ`s to power brakes using the later dual diaphragm YJ booster and MC. Both had maunal brakes before. Did not touch the prop valve at all. YMMV.

If you are looking for additional stopping power I would sugguest contacting Savvy off road.....Blaine Johnson.......As they offer a brake pad that works very well with Jeep brakes.

 

[tevans59]

Thanks bro will do, also found a web site that has a lot of info on brakes masterpowerllc.com

 

[jeepindavis]

Using a YJ booster mounted uside down the push rod rotates so it did not care , so does it matter?

So, why'dja filp the booster? better fitment?

 

[jeepindavis]

Using a YJ booster mounted uside down the push rod rotates so it did not care , so does it matter?

So, why'dja flip the booster? Better fitment?

 

[tevans59]

I put the writing face up on the power booster who knew it was suppose to be upside down.
I also changed out the old manual master for a YJ type cause I was just not getting what I thought I needed for braking, well after reading some info from the masterpower web site decide to check the vacuum only had 6 inches of vacuum , fixed that issue now have 15 inches of vacuum, so I really did not need to swap out MC. well live a learn that what these forums are about just no one ever said check your vacuum.
I have learned a lot from this job as in tweeking the rod that pushes inside the MC only takes the smallest adjustment to change the pedal feel. Got so good at it thought I was a nascar pit crewman

 

[jeffgt500]

I have a question about what you were experiencing before upping the vacuum. I recently added a used booster from a 91 or 92 YJ and added a new master cylinder for the same...My question is: When you go to stop, did your pedal go all the way to the floor slowing gradually? (I would be going about 25-30 mph and take about a city block to stop). I have bleed mine 3 different times and still no difference. Just looking for where to start looking for my problem.

 

[tevans59]

No mine did not go all the way to the floor but close but it stopped ok, some said they could lock up tires so that was what I was looking for.
I rebuilt the rear brakes completely and replaced front calipers and new pads also.
Did you bleed the master cylinder?
Here is a starting point check vacuum needs to be aleast 15 inches
Also the booster rod may not be adjusted correctly, it is adjustable as you seen.
Here is how I got to starting point for the rod.
Lift front end off ground remove MC and adjust the threaded rod out about 1 turn, try to mark it so you know where you are at cause this will take a few times , replace MC spin tire , hear any brake scrub? No do it again, if you do then test drive it.
Take the wrench that removes the MC with you , if you start to feel the pedal getting firmer then you will need to adjust the rod back in, you will know if you have to much brake you may smell them, firmer or hard pedal and you can not roll jeep by hand.
Know it sounds like alot but you will be suprised how quick you will be able to tweak it, when you get to that sweet spot it only takes a fraction to change the adjustment, just remember you want get that new car stop just a great feeling that you dont have to plan your stops
Oh yea you should have about 1-1/2 of pedal play before you feel something.

 

[jeffgt500]

Thanks alot. I am pretty sure that my issue is with the rod length now. I have changed vacuum ports and still the same with no other issues with vacuum, and have bleed the master cylinder, and all the lines numerous times. Thanks for you help.

 

[tevans59]

Not a problem, glad I could help to a point, just remember if the pedal gets firmer just jump out and remove the mc and tweak the rod and you are back on the road again in minutes.
Just wish everyone would tell us on these forums how to do it not just what to do.

 

[jeffgt500]

tevans59, thanks alot for your suggestions. I adjusted the rod between the master and booster and got them working ALOT better. I am running 33" tires and if I try to "emergency" stop, the rear will lock up but the front won't. To me though, it's no different than a vehicle with anti-lock brakes. I am not sure they are as good as they could or should be, but I feel safe driving it on the road now. thanks again.

 

[Kane]

I have a question about what you were experiencing before upping the vacuum. I recently added a used booster from a 91 or 92 YJ and added a new master cylinder for the same...My question is: When you go to stop, did your pedal go all the way to the floor slowing gradually? (I would be going about 25-30 mph and take about a city block to stop). I have bleed mine 3 different times and still no difference. Just looking for where to start looking for my problem.

Did you do a proper bench bleed on the master cylinder? Most cases this will plague people and the air will not get removed by bleeding the system after it's installed.

 

[jeffgt500]

Yes. I bench bleed it. I am pretty sure I got all the air out, but I am not positive. I will probably try and bleed the entire system again one of these days, but for now it has good brakes, just not sure they are as good as they could be.

 

[mb22753076019]

One other thing to consider is that, the firmness of a brake pedal is directly related to the rear brakes. Make sure your rear shoes are adjusted properly. Also double check your master cylinder if adjusting the rear brakes doesn't help. A master cylinder can bypass and give you a pedal that fades all the way to the floor.