How to test brake booster?

[homebrew]

I suspect that my brake booster is bad. The pedal is very hard and it takes a strong leg to get the jeep to stop. I haven't pulled the drumbs off yet but I made sure there was slight and equal drag on both the rear wheels, replaced the front calipers with some freebies that appear to be in good shape(no change in pedal feel with the ones I took off) Is there a way to test the booster? I am deploying soon and need to make sure that the Jeep is safe for the family while I am gone. Thanks in advance.

 

[Nickfast]

You have ABS or not?
If not, put your foot on the brake and start the engine.
If the booster is good, you should have some pedal drop when the engine starts. Listen for hissing while the engine is running and you apply the brakes.
If you have ABS, turn the key on (don't start) and listen for a chattering noise from the passenger side of the engine compartment (pedal should also sink at this point).
The booster for this system is under the coolant reservoir.

Nick

 

[balrog429]

If there's hissing when the you apply the brakes in the non ABS system does that mean the booster is bad?

 

[Shorty]

you may hear a slight "woosh" as you apply them, but it shouldn't be a constant hissing. If it continues past the initial pressing of the pedal, the diaphragm in the booster has failed.

 

[ehall]

easiest way is to check for vacuum. you should have 15-20 hg inches constant at warm idle, should drop about 5 hg inches when brakes are applied, and then climb back to normal position as the booster recharges

the booster is just a big vacuum sink

 

[homebrew]

there is no pedal drop with foot on brake with engine started. =Bad booster?

 

[homebrew]

Will a booster and mastercylinder from a jeep with ABS work on my non ABS equiped Jeep? A buudy offered them up for free, cant beat the price.

 

[Nickfast]

Will a booster and mastercylinder from a jeep with ABS work on my non ABS equiped Jeep? A buudy offered them up for free, cant beat the price.

Nope-way different system.
The Sherwood U-Pull-It has a '95 that has the standard system.
This is a dual diaphragm booster that would almost double the assist over yours when working properly.
I would get all hydraulics off of that and put it in yours if I were you.

Nick

 

[homebrew]

OK deploying in less than a month, Looking for a quick easy and cheap replacement/upgrade that doesn’t require having to replace the pedal assembly if possible any help is greatly appreciated.