78’ FJ55 brake bleeding issues (1 Viewer)

[jestlurnin]

Hello all.

78’ FJ55
-New brake master from cruiser outfitters
-New rear brake cylinders from cruiser outfitters
- bench bled new master after bolted up to brake booster.
-adjusted rear drums all the way out.
-started bleeding drivers side rear first as it’s the end of the brake line, then went to passenger side rear, then drivers side front, finished with passenger side front.

No bubbles on completion of bleeding and pedal goes dang near to the floor but can pump it up to a decent pedal height.

What am I missing. This is about the 50th time I’ve bled brakes on a cruiser and never had this issue.

 

[Pighead]

Do you have a residual valve in the rear brake line?
If you expand the shoes all the way out, stopping the rear wheels from turning, does the pedal still go to the floor?

 

[Skreddy]

Did you check the pushrod adjustment between booster and master cylinder?

 

[ceylonfj40nut]

Are your bleed valves on the top? If not you will have a hard time getting air out.

 

[jestlurnin]

@Pighead I’m 99% I do. But just to double check anyone have a picture I can reference? I’ll climb under there and snap a shot in a bit.

@Skreddy i did not nor do I know how or the specs. Looks like I’ll be doing some research.

@ceylonfj40nut the rear brake cylinders on my 78’ 55 are not on top/bottom but rather in front of and behind the axle so the bleeders are all on top I guess.

 

[jestlurnin]

@Pighead Is this my residual valve? And if so what’s the diagnostic procedure on it.

Brakes worked great prior to me doing a ton of work on the 55. Then when I test drove it for the first time after all the work the front bowl was leaking so I thought might as well get after the entire system. And here I am..

 

[Pighead]

@Pighead Is this my residual valve? And if so what’s the diagnostic procedure on it.

Nope. That's just a brake line T fitting.
IIRC, residual valves are in the MC where the brake line originates. Show us a pic of your MC please?

 

[SteveH]

I know you said you adjusted the rear brakes. In my experience, the shoes need to be lightly dragging on drum as you turn the drum by hand. That's how tightly the shoes need to be 'out'. Anything less, and you won't have a pedal.

 

[jestlurnin]

@Pighead here are a couple shots of my master and what I always referred to as a proportioning valve. Under the master on the booster. We talking same thing just different terms?

 

[Pighead]

@Pighead here are a couple shots of my master and what I always referred to as a proportioning valve. Under the master on the booster. We talking same thing just different terms?
View attachment 3047409View attachment 3047410

That is the proportioning valve. It proportions how much braking force is applied front vs. rear.
Residual valves keep some residual pressure in the brake lines so that your shoes (or pads) don't move too far away from the drum (or disc).
Traditionally, they live right where the brake line connects to the MC. I bet yours are right under those big brass fittings on the top of your MC.

 

[73FJ40]

@jestlurnin

Are you certain the brake cylinders are properly located? All four rear brake cylinders on my '73 FJ40 are different, due to plumbing and bleed screw locations. Because the bleeder valve is "centered" on the bleeding cylinder, if that cylinder is installed on the wrong side, I think it will be bleeding from the bottom of the cylinder, with no effect.

Also, when I bled my brakes, I cranked the shoes up tight against the drum on both cylinders, absolutely no rotation of the tire. My theory is that with the wheel cylinder prevented from moving, all the pressure from the brake pedal during the bleeding process will be to compress air, and not waste effort moving the cylinder cups on a blanket of air. Once the bleeding is over, I back off the adjusters for the minimum drag while the wheel turns.

On my truck, the driver's (left) side adjusters are right hand thread, and the right side adjusters are left hand thread. The slots on the ends of the brake cylinders are narrow and wide on opposite ends, to ensure the wide and narrow ends of the shoes are properly indexed. If you look closely at the FSM, the lining on the brake shoes is offset to one side to improve braking performance I suppose.

I can't speak to the differences between FJ40's and FJ55's, but I suspect Toyota logic on rear drum brakes should be fairly consistent.

 

[jmylie]

Not sure about a 78 but my 77 was always a pain to bleed.

Mine has 2 wheel cylinders for each rear wheel. When adjusting the rear brakes make sure to adjust each cylinder as evenly a possible.

The bleeder valve is on the brake cylinder closest to the front of the vehicle.

Having a helper gently pumping the brakes helps too.

 

[jestlurnin]

@73FJ40 I’m positive the cylinders are in their appropriate location. I put the new ones back exactly where the old ones were. And with the way the hardliners are situated orientation really only works one way.

I think I’ll re-attempt to evenly clans the cylinder until I lock the wheels up then try and bleed again.

With no leaks and no fluid being lost from the reservoirs it’s the only thing that makes sense. Other than like Skreddy said to check the push rod adjustment.

 

[AntFarm]

Make absolutely sure that both pads on a single wheel are adjusted fully out. It’s possible for just one of the two pads to lock up a wheel, which can fool you into thinking both pads are fully out. Crank just one completely out until it locks the wheel tight then start to back it off one click at a time until the wheel rotates with drag. Then repeat with the other pad. Only then will that wheel be adjusted correctly. There will be a lot of drag. More than you think there should be.

 

[jestlurnin]

Everyone, what the heck am I missing here?

I’m tightening the star in the 1st picture below (it is on the cylinder that is in front of the rear tires) by moving the handle of the adjusting tool away from the axle. The note I wrote myself literally says “handle of tool moves away from axle towards front of rig”, which means the star is moving towards the axle. Conversely the second picture is a shot of the adjusting tool in the slot to move the brake cylinder that is on the back of the assembly. The note I wrote for that one says “handle of tool moves away from axle towards back of truck to tighten”

The slot to adjust the front cylinder is on top. The slot to adjust the rear cylinder is on bottom.

The star gets hard as heck to turn. The wheel feels like it’s getting harder and harder to move then when I really grab a hold of it and give it a couple solid spins it feels like I’m back to square one where the wheel isn’t even close to being locked up. As if the shoes were self adjusting

I’m attempting like @AntFarm said to lock out the front cylinder, back off a click then lock it out with the rear cylinder as to have the cylinders adjust out evenly.

I have probably turned the star 50 clicks and I can still move the wheel by hand. Do I need to bite the bullet and replace drums and shoes? The only thing I have not replaced on the brake assembly. When I had the drum out I did not measure them, perhaps they are beyond the point where the shoes can grab? This seems unlikely as I had a great brake pedal prior to “fixing” these.

Any new suggestions are 100% welcome!

 

[jestlurnin]

I bit the bullet and took the drums off again…does this mean new drums are in order? I see max diameter at 11.5 inches which seems to be where I’m at. It looks like there is plenty of meat on the shoes but if I’m gonna replace drums might as well replace shoes as well.

What does everyone think? Also included some shots of the entire assembly in case I’m being an idiot in another respect.

 

[73FJ40]

I would measure the distance between the top and bottom shoes at 12 and 6 o'clock. How close to 11.5 inches?

Next, with the drum removed, I would adjust the cylinders to expand them, to see how far they have to move to get to 11.5 inches.

At least this will give you an idea on how worn out the components are.

 

[AntFarm]

As far as adjusting the cylinders, I recommend you read through Coolermans write up here: Brake Bleeding 101 - http://www.globalsoftware-inc.com/coolerman/fj40/15E.htm
It’s the best write up you’ll find anywhere. Brake drum diameters are usually measured with a caliper which you’ll need to do in my opinion in order to determine if you have enough thickness left. A tape measure just isn’t accurate enough. Having perfectly round drums also helps when adjusting the cylinders. Prior to mounting the drums, turn out both adjusters by hand (evenly!) as far as possible and still be able to get the drum mounted back on. This minimizes the amount of adjusting with the tool.

 

[jestlurnin]

Ok so thought I’d just throw more money at the brakes Coolermans description is spot on and what I’ve been trying to do..

New drums from Toyota and shoes from Napa.

It appears the slots associated with the end of the new brake cylinders with the adjusting star I picked up from cruiser outfitters are too narrow to accept the width of the new shoes. Now mind you these are not OEM shoes and the cylinders are aftermarket Japanese brand from cruiser outfitters. So who the heck knows if the aftermarket shoes are incorrect or the aftermarket brake cylinders are incorrect!

I threw in a picture of the old VS new brake cylinder slot to show the difference. New one on top, old on bottom. I have no idea if the old cylinders are OEM and can’t find any TEQ logos on them.

Plan is to now throw more money at the problem and order a set of OEM shoes if they are still available and see if they fit in the new aftermarket cylinder slots. If not I’ll have to go back to cruiser outfitters with the problem.

The battle continues….if anyone has any more insight I’m all ears.

 

[jestlurnin]

First picture is of adjusting nut (no idea if that is the correct lingo) from new aftermarket Japanese cylinders the second picture is from the cylinders that were on the 55. No idea if the old cylinders are OEM. The diameter of the two nuts is different as well or I’d just swap them old nuts onto the new cylinders and be on my way.