88 2W/D Pickup DLX 22r with P/B:

Just had my master cylinder rebuilt, and now that I have reinstalled it, power bled system, set rear shoes correctly, I'm finding that my pedal free play travel is excessive.

I want to verify the power booster pushrod pin setting, but I don't have the tool for it.

So I searched online and I am not seeing any advertised to work on Toyotas of our vintage (except a factory version for $195, ahem, you know where they can put that!). However I did see at least one well-reviewed tool that works on Chevy Corvettes and Nissan Maximas, but NOT on at least one Toyota, a 2000 Tundra. So, I am guessing some tools work on some groups of vehicles, and some work on others.

So if you have used a power booster pushrod pin gauge on your 86-95 Pickup/4Runner, Please tell me so I can get the right one.

Or if there is an alternative method for this setting, I'd love to know that, too.

Thanks,

Mike

 

You ought to be able to feel the freeplay simply by moving the pedal by hand and lengthening the rod until the pedal free movement is a reasonable minimum.

 

What if doing this causes preload on the master cylinder. Should I worry about this?

I thought free play was an indication of a gap between the booster plunger and the master piston. Not some you can physically observe, but you can measure if you know how.

​

 

Of course there must be no pre-load, or the master cyl cannot release pressure back from the wheel cylinders.

If you understand the relationship of the pedal, booster and master cylinder components and you have a light touch, it is possible to feel when the free play is sufficient without giving any excessive free motion that decreases pedal height on brake application.

I have successfully adjusted any number of brake rods without the use of any special tool

 

I lack the "right touch." I'll probably have to take it into the shop. Thanks

 

Far as I know, only "tool" you might need is a ruler. A thin metal one is the easiest to fit down there.

The FSM has a good, easy to follow, procedure for adjusting the pedal, etc.

PS: Make sure that when you bleed the brake system that you 1) ensure that the fluid in the MC never gets below about 1/2, and 2) you don't forget to bleed the LSPV last of all. Many people forget/ignore the LSPV, but it's an integral, important part of the brake system. Two very important things to remember.

Have fun!
Pat☺

 

Went to my mechanic today. He said the booster pushrod is not adjustable while installed: Got to remove the booster and keep the shaft from rotating on the input side in order to loosen the locknut on the output side.

But he said he can move the pushrod forward by making the pedal rod longer from inside the cab.

This is way beyond me. I'm going to have to leave it to him.

But I do appreciate learning what you said about bleeding the lspv. NOBODY knew what to do about that thing and I have been running around trying to get mechanics to pay attention to it. The lspv is at the core of a long headache over this brake system. But I'm finally almost have it worked out.

Thanks

Mike

 

A lot of the time, if the LSPV has been ignored for a long time, it can get clogged, have air in it, or misc crud and corruption. It can make the brake system feel mushy or loose. It should be bled last of the whole process. I've found it's a good idea to take it's sensor arm loose from the axle, and move it through it's range a few times before bleeding it. It can help break up the crud clogging it up.
It's all out in the open, easy to find, easy to work on, easy to bleed.

Good luck!
Pat☺

 

The oem tool was pricey, but you can get inexpensive plastic ones for $10-$15

 

This is what I used to adjust the booster pin length on my 1984 Toyota pickup and 2001 Toyota Camry. It worked well on both applications.

 

Some of the reviews said that the inexpensive plastic gauges are just stir sticks and really pieces of junk.

The better plastic ones apparently don't work for my vintage. Again, the reviews.

​​So I have an appointment in a few weeks to put this in the hands of my regular mechanic, who's really excellent.

Thanks for the feedback and help.

 

Why bleed the LSPV last isn't it between the rears and the master. Wouldn't the bleed order be LF RF LSPV LR RR?

 

That's according to all the FSMs I've read. Passenger Rear, Driver's Rear, Passenger Front, Driver's Front, LSPV.
Just WHY they call out the LSPV last, I don't know, but it's always worked fine for me. May have something to do with the LSPV controlling the amount of fluid going to not just the rear, bbut the front as well. I just don't know. I'm not a Toyota Engineer, nor am I a brake specialist. I just "do it" the way the Book says to.
I bleed the brakes out no less than every 3-4 years, sometimes every year, depending on the amount of moisture in the air. Every time I do, I take the control arm for the LSPV off the axle and flex it through it's throw a few times before I bleed the LSPV. Makes sure there's nothing stuck where it shouldn't be.

All just me, though. As they say, you do you
Pat☺

 

“Just WHY they call out the LSPV last, I don't know”

Maybe because the lspv has the highest bleeder valve in the system. But that’s just a guess.