correct install of drum brake adjusters?

[Blueman2]

Can someone confirm the correct direction of rotation for the brake adjusters in the rear drums?

Looking at the rear brakes, it appears that the star wheel should rotate up to expand the shoes. For the driver side this would be counter-clockwise viewed from the front. For the passenger side it would be clockwise viewed from the front. I just want to make sure I did not get the adjusters switched by accident. I had both axles out for seals and bearings and while I thought I kept each side separate, I want to make sure.

I just did rear brakes and the 199mm Tundra upgrade on my son's '96 Limited and pedal feel is soft. I used the home made pressure bleeder, did the rears first then the fronts. I also followed the instructions in the manual for the brake booster bleed, 40+ brake pedal pumps with ignition off, key on, listen for pump, only runs a very short time, then 20+ pedal pumps with key still on. Did this a couple of times.

When I took it out to break in the new pads, I found the pedal very soft and could put it to the floor without locking the brakes.

ABS not currently working, I believe because of faulty install of ABS rotor on right rear axle by dealer, pressed on too far. Going back to dealer Wed to get this resolved.

 

[BTO]

Looking at the rear brakes, it appears that the star wheel should rotate up to expand the shoes. For the driver side this would be counter-clockwise viewed from the front. For the passenger side it would be clockwise viewed from the front.

Sounds correct.

When I took it out to break in the new pads, I found the pedal very soft and could put it to the floor without locking the brakes.

The pedal goes to the floor? My guess would be the master cylinder is shot. Getting the rear brakes to work well may help some. I found when doing them, they work much better when the shoes slide easily on the back plate.

 

[TheDurk]

Did you bleed the brakes? Before you panic, a good bleed is a good idea. If you let the piston slip out of the cylinder while you had the shoes out (easy to do), then it's a must. The only thing holding it in place with the shoes out is the flimsy rubber boot.

There is also a procedure in the FSM for bleeding the MC on the truck. Air in the MC can cause those symptoms. This happens if the reservoir goes dry for any reason while you are messing with stuff.

 

[Blueman2]

Did you bleed the brakes? Before you panic, a good bleed is a good idea. If you let the piston slip out of the cylinder while you had the shoes out (easy to do), then it's a must. The only thing holding it in place with the shoes out is the flimsy rubber boot.

I actually installed new wheel cylinders, the old ones had a fair amount of rust on the bleeder seats. The pistons never came out of their bores while I was putting it all back together. After assembly, I bled the rears, starting on passenger side. I used the home made pressure bleeder, pressurized the MC reservoir to about 15PSI

There is also a procedure in the FSM for bleeding the MC on the truck. Air in the MC can cause those symptoms. This happens if the reservoir goes dry for any reason while you are messing with stuff.

I think I did this. All I could find was the procedure detailing 40+ pedal pumps with ignition off, then turn ignition on and check for pump run time. After turning the key on, the pump only ran for a few seconds. The FSM says it should run no more than 30-40 seconds after turning on the key. Mine ran for less than 10. After turning on ignition, pump pedal another 20+ times. I actually ran through this cycle a couple of times.

The pedal goes to the floor? My guess would be the master cylinder is shot. Getting the rear brakes to work well may help some. I found when doing them, they work much better when the shoes slide easily on the back plate.

I used some caliper pin grease on the backing plate friction ponts indicated in the FSM, also in the adjuster threads.

At this point, I think the shoes are not properly adjusted so I will check the adjusters and make sure they are working, then adjust the shoes, bleed the lines again and see if that improves things.

If I understand the brake set up correctly, I should be able to see the adjustment mechanism working if I pull the drums and have someone apply the parking brake. As the e-brake is pulled, I think it should move the adjustment lever so that it rotates the star wheel. As the e-brake is released, the adjustment lever should move back into position and click down over the star wheel teeth,


Another possibility is that some of the star wheel teeth have worn to the point the lever won't push against them properly. Will check that also.

Thanks for comments.

 

[BTO]

If I understand the brake set up correctly, I should be able to see the adjustment mechanism working if I pull the drums and have someone apply the parking brake. As the e-brake is pulled, I think it should move the adjustment lever so that it rotates the star wheel. As the e-brake is released, the adjustment lever should move back into position and click down over the star wheel teeth,

Another possibility is that some of the star wheel teeth have worn to the point the lever won't push against them properly. Will check that also.

More likely the adjusters are sticking. Take them apart, clean and lube so that they turn with ease.

You have the e-brake to adjuster operation correct. They will only click if you have enough slack in the brakes to allow it.

 

[TheDurk]

I think I did this. All I could find was the procedure detailing 40+ pedal pumps with ignition off, then turn ignition on and check for pump run time. After turning the key on, the pump only ran for a few seconds. The FSM says it should run no more than 30-40 seconds after turning on the key. Mine ran for less than 10. After turning on ignition, pump pedal another 20+ times. I actually ran through this cycle a couple of times.

This from the 2002 on-line FSM, I assume? The earlier systems are different. I was talking about a procedure in my '99 FSM that is not in the 2002 manual. It is also in the '96 Tacoma FSM that you can find here:

http://www.ncttora.com/fsm/1996/96_repair_searchable.pdf

I had to use this the first time I used my own homemade pressure bleeder and let one of the reservoir halves go dry. There are two compartments, and you have to watch both--I learned this the hard way. This is a really easy mistake to make with this type of bleeder.

The fix is really simple to get the air out of the MC and you will find it on page 1205 and 1206 of the .pdf linked above (pp. BR-5 & BR-6 of the actual book). Then you have to rebleed the rest of the system. If you think there is ANY chance you let the reservoir go empty, you should try this. I had exactly the same problem and this was the fix.

I'm sorry to send you to a huge download, but I have never figured out how to clip a piece of a .pdf and this is the only place I know to find this on-line. My '99 FSM is one of those paper things. Hope this helps.

 

[Blueman2]

Yep the 40+ process was from the '02 online FSM. Thanks very much for the download, no prob, I did a right click, "Save Target As" and it did not take long at all.

I will give it a shot. I don't think I let the MC go too low but I may have.

I did clean and lube the rear drum adjusters when I had everything apart, they turned easily by hand before assembly. I just want to make sure I put each one back on the correct side and verify operation. After that, will bleed MC following the new (to me) procedure, then bleed all four lines again.

When I assembled the bellcranks, I followed the FSM and set the .025 clearance to the backing plate when the slack in the inside bellcrank cable was just taken up. I then adjusted the hand brake lever cable so that the screws in the bellcranks were touching the backing plate. In this condition, the brake lever comes up too easily and too many clicks. That is partly why I think the rears are not properly adjusted. The FSM spec is 7-9 clicks.

Thanks again for all comments, you folks are a wealth of info.

 

[TheDurk]

You can see the adjuster tighten the shoes just by pushing on the lever with your fingers with the drum off. Just move it back and forth and the shoes should move outward as the pawl pushes the screw. If they get closer together, you have the adjusters backwards.

You left a very important data bit out of your otherwise detailed posts...is the e-brake working? If you put the drum on with the adjusters to minimum position, and then you operate the e-brake until the shoes adjust--the fact that the e-brake engages nicely when you are done pretty much guarantees that the adjusters are doing their job. Then you set the handle to the 7-9 click spec.

One other thing. Are you using factory shoes? There are some aftermarket shoes that are not the right profile and the brakes won't adjust right no matter what you do. There is a thread or two that mentions this. I haven't seen it myself.

 

[Blueman2]

You left a very important data bit out of your otherwise detailed posts...is the e-brake working?

Not as well as I think it should. Everything seems to move properly when I pull the lever up but the e-brake won't hold the vehicle in drive at idle. I tried setting the brake lever to 7 clicks but when I checked the bellcranks after adjusting the handle, they were nowhere near the backing plate.

That did not seem right so I reset the lever adjustment till the bellcrank stop screws were touching the backing plate and the e-brake cable was slack to the touch. This is part of what led me to think the brakes were not properly adjusted.

One other thing. Are you using factory shoes? There are some aftermarket shoes that are not the right profile and the brakes won't adjust right no matter what you do. There is a thread or two that mentions this. I haven't seen it myself.

Yep, factory shoes, I had read that recommendation in a couple of the axle seal & bearing threads so I went that route

More likely the adjusters are sticking.

Upon removal, adjusters were disassembled, cleaned with solvent, wire brushed by hand, then re-assembled using some caliper pin grease as lube. They turned easily by hand throughout their adjustment range.

Will be doing my checking this morning and will report back.

Thanks.

 

[BTO]

Yep, factory shoes, I had read that recommendation in a couple of the axle seal & bearing threads so I went that route

Upon removal, adjusters were disassembled, cleaned with solvent, wire brushed by hand, then re-assembled using some caliper pin grease as lube. They turned easily by hand throughout their adjustment range.

You may be at the same place I was at with our 4R a while back. See this thread: http://www.toyota-4runner.org/3rd-gen-t4rs/90112-one-simple-question.html

My adjusters were working perfectly but I just could not get enough braking power from the rear drum brakes. I cleaned, filed, sanded and greased till I got the shoes sliding on the back plate nicely (Pay close attention to to all contact points and the wedge block at the bottom). At that point the rear brakes began working. I was playing around, jamming on the e-brake so much that I made the adjusters ratchet down too much and the brake were smoking hot. I had to back them off through the hole in the back plate.

What I learned was 4R drum brakes only use one shoe at a time, but they will do an adequate job of stopping if they can move and wedge into place. It's called the "servo effect".

 

[Blueman2]

Thanks, that does give me something to think about. I bought an off the shelf hardware kit when I re-assembled the brakes. I found that the kit came with two sizes of the pins that retain the shoes to the backing plate. Even the longer of the two was shorter than the pins I removed. I may invest in a set of OEM pins and see if they are longer. I can see that the shorter pin would increase the force required to move the shoes around.

 

[Blueman2]

Okay here is an update.

I bled the MC per the Tacoma FSM provided earlier, (thanks to TheDurk), I did one port at a time. The front port definitely seemed to have air as the first couple of pedal pumps did not produce much of anything. The rear port squirted fluid from the get go. Got those buttoned up, topped off the MC.

I pulled the rear wheels and observed the adjusters. Just as an aside, the star wheel rotates counter-clockwise on the passenger side and clockwise on the drivcer side. Both adjusters were working fine. I put the drums back on and had a helper push the pedal and simultaneously work the e-brake lever a few times. I could hear the adjuster on the driver side working and the e-brake lever tightened up.

Checking the passenger side, the bellcrank is not returning to the home position against the backing plate. I think shoe friction may be the issue.

I engaged the e-brake and it did feel better. I put the wheels on and torqued up the driver side. When I started torquing the passenger side, it was clear the brake was not engaged. I manually adjusted the star wheel through the port in the back until I could not turn the wheel by hand. It still moved a tad when torquing the lugs.

Took it for a quick spin, pedal feels better but still not where it should be. May still need to bleed the fronts. Backed down the driveway without realizing e-brake was still engaged. E-brake still will not hold in drive at idle.

At this point I am done with it. I have been working on various things on the truck for three weeks now and am fed up. Back to the dealer it goes!

Here is what I accomplished so far

cat back exhaust and #2 O2 sensor
fabbed a patch for the driver seat front left side mounting bolt/nut
rebuilt the seat frame (broken rail and failed seat back adjuster mechanism)
replaced both cushions on the front seat
the '99 console mod
the Tundra 199mm front brake upgrade
rear bearings pressed off and on (what a hassle with the dealer on that, three tries to get it right and I still think it has a problem)
installed new rear axle seals
replaced one of the bellcrank pivot blocks (unit frozen with sand & salt, block cracked)
new rear wheel cylinders, pads and hardware

Thanks for all the info and assistance provided. I will see what the dealer says about the brakes and the ABS light. I think the ABS light is on because they pressed the ABS sensor ring on too far.

When I pulled the left drum today, there was oil in the drum. Either my new seal install failed or the dealers install of the bearing retainer is on too far. Will ask them about that also.

AAAAAAAAAAAAAARRRRRRRRRRRGGGGGGGGGHHHHHHHHHHH!!

 

[TheDurk]

For your future reference, and the benefit of eventual searchers, this write-up was just posted by Matt (Nelsonmd) over on YT. It's a good one and I hadn't seen it before.

http://www.google.com/u...-sticking-parking-brake-bellcranks-toyota-truck-park-brake-bellcrank-repair.pdf...hQ

 

[Blueman2]

Thanks for that info. I had essentially done the same thing without the bead blasting and painting. The bellcranks are working properly.

I went ahead and replaced the pad retainer pins with OEM, the generic set were about an eighth of an inch shorter than OEM. I rechecked and readjusted the bell cranks, then set the parking brake. I then manually adjusted the star wheel on the right until I could not turn the drum with 60 lb-ft on the torque wrench, similar to left side.

After that adjustment, I bled all brakes, rear then front. This last round seems to have done the trick./ The pedal feel is much improved, the e-brake will hold in Drive at idle and will hold in reverse on the sloping driveway. The lever takes about 6-7 clicks to set and feels good.

Thanks for all the links and suggestions, they helped a lot.

Now if only the axle seals hold up so I don't have to mess with it all again.