Brake Booster/MC Swap

[summerinmaine]

My booster on the 87 MJ appears to have taken a dump (diaphragm leak), so I picked up a 2D booster/MC/prop valve/pedal assembly from a 1996 XJ. I figured it would be easier to swap everything than worry about matching/modifying the new rod to fit the old pedal.

 

I imagine I'll have a bit of clearance problem between the new booster and the stock MJ washer bottle position (looks pretty tight with the added length), but I'm willing to pull the bottle and try to find a smaller replacement. Any other problems I should anticipate in making the swap? Any spacers needed?

 

Thanks for any advise.

[HOrnbrod]

My booster on the 87 MJ appears to have taken a dump (diaphragm leak), so I picked up a 2D booster/MC/prop valve/pedal assembly from a 1996 XJ. I figured it would be easier to swap everything than worry about matching/modifying the new rod to fit the old pedal.

 

I imagine I'll have a bit of clearance problem between the new booster and the stock MJ washer bottle position (looks pretty tight with the added length), but I'm willing to pull the bottle and try to find a smaller replacement. Any other problems I should anticipate in making the swap? Any spacers needed?

 

Thanks for any advise.

 

You did well picking up the pedal asembly as sometimes the 95/96 booster rod fits your existing pedal w/o mods (91-92 MJs w. auto and non-ABS). Other MJs need mods to the booster arm and/or pedal, depending if it's ABS or not, or manual/auto tranny. You will need the 1/4" aluminum spacer plate that goes between the booster and firewall; hope you picked that up too. You can move your existing washer bottle forward about an inch too to have clearance from the booster.

[offroader461]

i have an 87 and am trying to install a 96 booster master and XJ valve...if i buy the 96 pedal assembly and brake light switch i do not need to modify the rod to get my brake light to activate...just adapt the wiring correct...I'm trying to make this as simple for me as possible..

[summerinmaine]

You will need the 1/4" aluminum spacer plate that goes between the booster and firewall; hope you picked that up too.

 

I'm pretty sure that's included, but I'm checking now. Thanks.

 

You can move your existing washer bottle forward about an inch too to have clearance from the booster.

 

I hope I can move it forward an inch, but there's a vacuum hose that appears to interfere. Maybe I can just re-route it.

[HOrnbrod]

i have an 87 and am trying to install a 96 booster master and XJ valve...if i buy the 96 pedal assembly and brake light switch i do not need to modify the rod to get my brake light to activate...just adapt the wiring correct...I'm trying to make this as simple for me as possible..

 

Good point. The 91+ brake switch is different than earlier years, it's a dual contact switch, one for the brake lights, and one for the cruise control system. It should line up and be a bolt in mechanically and all you have to do is adapt the brake light wiring. I did not use the XJ prop valve, and kept my MJ combo valve intact, fabbing my own brake lines from it to the M/C since I retained my working rear load leveling valve.

[summerinmaine]

Yep, the spacer plate is part of the package I bought (it wasn't shown on the pic of the booster), so it looks like re-positioning the washer bottle is my only other unknown issue (I've already looked at the prop valve/brake light threads so I'm covered there).

 

Thanks for the help.