Troubleshooting very soft brakes (1 Viewer)

[bpenn1980]

I thought I would post this after taking it to a mechanic.

A very simple way to locate where your braking problem lies is to use vice grips and clamp off your brake lines to locate the trouble.

For example, use a vice grip to clamp down the brake line that goes to the rear brakes, right before the LPSV. Now, Press down on the brakes, if your pedal still goes to the floor, leave the vice grip clamped down on the rear brakes and clamp down your front left brake line right before the caliper and press the brake pedal again. Now the right side, press down on the brake pedal, if it still goes to the floor, and your FJ80 isn't equipped with ABS, 99% chance you have a bad master cylinder. You have eliminated the possibility of any air behind the vice grip clamp and any potential problem with brake adjustments, leaky calipers, etc.

I will be ordering a master cylinder from C-Dan and report back here in a couple days.

I hope this will help anyone in the same boat I am in, I did a LOT of searching before I posted this and I read a lot of posts on here, but never read about this method to troubleshoot for a bad MC. I'm sure people on here have done this before, I'm just posting as I learn

Thanks for passing this along.

 

[digital]

Sorry I didn't post up earlier and save you the mechanic's fee...

No worries, consider it a free addition to the knowledge base

 

[Blue Phoenix]

Sorry for all of your troubles....Im sure this post will go to good use in the future.

 

[Northernstar]

A very simple way to locate where your braking problem lies is to use vice grips and clamp off your brake lines to locate the trouble.

I'm also (naively) tracking this problem. Are you talking about regular old vice grips? The brake lines strong enough to handle this? How about a C clamp?

 

[Ebag333]

I'm also (naively) tracking this problem. Are you talking about regular old vice grips? The brake lines strong enough to handle this? How about a C clamp?

You want them tight enough that the pinch, but you don't want to completely lock them down on the line. Think more clamp and less "vice".

A C clamp should work just as well, though it may not pinch the line as much.....

Really all you want to do is slow down as much fluid as possible, you don't need to completely cut it off.