FrankenBooster? yj booster cj master with yj guts? -
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post #1 of 1 Old 05-11-2011, 07:11 PM Thread Starter
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1983 CJ7 
Join Date: Apr 2010
Location: Raleigh NC
Posts: 720
FrankenBooster? yj booster cj master with yj guts?

So I got into my Yj dual diaphragm swap only to find out its a single booster. $#!^...
I decided to experiment a little, I separated the YJ MC from the YJ booster and the same with the cj stuff. The Yj is a 1995 and had a significantly deeper socket for the rod into the MC, about 1/2"-3/4" diffrence.
I took the circlip off and removed the guts from the Yj MC and measured them, they were virtually identical bore and stroke. I then inserted the Yj guts into the cj MC, creating a MC with the correct fittings for my cj lines and the correct depth for the Yj boster and rod. I did have to do some creative trimming and drilling to fit it to the booster. about 0.2" diffrence in the bolt pattern, and the bottom of the MC is round not "V" shaped.
After putting the whole assembly back in the the wrong way several times, I took it around the yard. The pedal grabbed good but went to the floor before engaging.
I followed the link from the BustedJeep writeup, And cut and lengthened the rod. I now have great stopping power (the orig. cj booster was total crap and worn out) but the pedal is about 4-5" too high and has a very long take-up before engaging the MC plunger.
My new idea is to make a bolt and stop assembly to adjust the pedal down. Will this hurt the booster being partially through the travel or did I miss something else. I rode it around and the brakes don't drag now and I can feel the MC engaging around where it used to, the pedal just travels about three inches before anything starts happening. Any ideas?

CrankyD is offline  

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