What's up guys, I've been going through some brake issues that's left me and a local shop stumped. Original problem was that the pedal went straight to the floor with no pressure. Replaced the master twice, put in a new booster, bled all four corners but couldn't get any fluid out of the drivers front. So I replaced that caliper but the problem persists. I've got the summit proportioning valve up next to the master also. I haven't tested the vacuum I need to find a gauge but that's the only other thing I can think of that would be a problem just not sure how I'd need to fix it. Any input would be gladly appreciated, thanks

 

Can't get fluid out of the driver's front caliper bleeder? Are you sure the flex line isn't blocked? (Disconnect it from the caliper and VERY GENTLY nudge the brake pedal.)

 

my guess is it's plugged too. try cracking the line at another point and see if you can get fluid out.

 

The flex and short hard line to the caliper are clear. I haven't checked the line from the t below the mc to the flex line yet I'll do that now

 

Vacuum bleed. only way i was able to get mine to bleed. I had same problem,

 

I bought a part store master cylinder one time. When I bench bled it, I could not hold the pressure back with my finger, but when I put it on the truck, it would not bleed and operate the caliper. My guess is the pistons in the caliper was able to apply more pressure then my finger and not let the fluid go flow like it should.

Even if the pistons in the caliper were frozen, it should of still flowed some fluid but it turned out to be the master cylinder on mine. Lots of threads on bad parts from part store. I would suggest getting an Aisin master cylinder.

I use a rubber tipped air gun and from the master cylinder connection with the lines from the calipers I am able to clean the lines out with low pressure air. Lots of rust comes out. I then fill the lines with Marvel Mystery Oil to help fill the line and blow them out. Flush again with brake fluid to get rid of the Marvel Oil.

 

If your able to bleed the right side .

It is not the master cylinder.

Get the plumbing correct when you installed the manual valve??

Someplace from where the front lines tee to the left caliper you have a crushed or blocked line.

I would guess when you removed the line from the left caliper there was no brake fluid in the line??

 

X2 for vacuum bleeder... made my last brake insanity MUCH easier to be able to work through (wayyyy too much) bleeding on my own.

Im sure you did but just to be sure.... You been bench bleeding the MC's?

 

I did bench bleed the mc initially a few weeks ago. Then again on the truck after disconnecting the lines this time. All of the lines are clear unobstructed to both sides bleeder. No luck with the vacuum bleeder on either side now or with the 2 person pump the pedal method but works on the rears. Going to give it another shot tomorrow. Thanks for all the helpful input. If nothing works tomorrow I'll probably pay up and get an aisin master.

 

Ok... all of that having been said an approach comes to mind. Were I in your spot I would try disconnecting the line at the caliper and MC and then blast through it with a compressor. If there is an obstruction that should shoot it out.
Just a thought

 

After today, blew air through the line from master to each caliper, no blockage. Went to vacuum bleed passenger first and couldnt get any fluid. Blew brake cleaner from bleed port to inlet on the caliper and it shot right through so no blockage. Tried vacuum again and nothing after about 5 minutes. Same with drivers side.

Afterwards, i connected a tube to the passenger bleeder from a bottle of fluid and depressed the pedal and let off. Fluid in the tube rose only about 5 inches above the top of the bottle after I let off then creeped back down.
With a tube from the master to the reservoir it operates fine while pumping the pedal. I don't know what else to think of to do

 

Bad Bleeder Valve

With it removed do you get fluid coming out

Caliper on Upside down??

Sure you have the manual proportion valve plumbed into the rear line??

 

Double check your line configuration.

If everything else on the brake system checks out, it sounds to me like it could be a lack of pressure coming from the master cylinder.

From your description above, it sounds like you can get some fluid from the passenger side but no fluid from the driver's side.

You may not have enough flow from the master cylinder.

When I replaced my master cylinder with a brand new one about a month ago, I had a similar issue where the rear brakes had a great flow out of the bleeders but the fronts only dripped a small amount.

Again, double check for line routing, bleeder blockage, etc. before throwing parts at it.

Good luck!

 

Manual prop valve is routed correctly. Calipers are correctly mounted. I pump the vacuum up to about 15 psI then open the bleeder and it goes down but no fluid. Like I said I've done it for almost 5 minutes with no luck. I'll give a better update tomorrow

 

Have you pressed the pedal a few times to get fluid in your calipers

I have never used a hand pump vacuum bleeder .

Mine is air operated .

I put the bleeder on the fitting hit the trigger crack the valve open pull air and fluid out for 30 to 45 seconds (just a guess ) close bleeder valve release trigger . Work around the vehicle repeat as needed.

I am not sure you might be doing something wrong.

I really wish I was close enough to help in person.

 

How are the Beck Arnley products? anyone have experience with them?

 

I take it you're thinking about getting a Beck Arnley master?

Did the price on a Aisin master cylinder shock you or are you having a hard time coming up with the correct part number?

 

Hard time finding correct part number, and yes after finding a few and seeing the price of them... alittle shocked. But if I have to then I'll suck it up

 

I am not as familiar with the 89-95 trucks but believe your tank is the square one. Is this correct to yours?

http://www.ebay.com/itm/OEM-Aisin-Brand-Brake-Master-Cylinder-for-Toyota-4Runner-Pickup-/351295234243?hash=item51cad3e0c3&vxp=mtr

 

that looks pretty similar. I guess I didn't search as deep as I should have. Thanks Terrys87