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[seapotato]

Haha, no rush.

Provided I can limp it home, I can use the other cruiser or swmbo's car if need be.

I'll try to order something tomorrow morning, then I'll know how long I have to wait.

 

[seapotato]

View attachment 2447783
Raybestos doesn’t list no brakes. Glad you’re OK.

bet you’d be happier with any/all of the listed signs.

The only time I lost all brakes like that was in a ‘77 F150 that’s rear brakes seals failed after a mechanic did a sh——-ty brake job. Not fun. Fortunately I had to hit the brakes at the top of the driveway... not on the road.

Yeah perfect firm pedal at one stop light, zero brakes at the next is a bit drastic.

Any warning would have been nice.

I'll go poke around a bit in a while, see if any brake fluid has shown up anywhere.

 

[Rigpig]

Had a similar thing happen on one of my old 60 wagons where the rubber flex lines were so old they would bulge and pedal would go to the floor. Everything appeared ok, no leaks, no fluid loss, just tired flex lines.
PS: i might have good used set in the tickle trunk that i'll throw in with the plastic wiper thingies.

 

[seapotato]

Had a similar thing happen on one of my old 60 wagons where the rubber flex lines were so old they would bulge and pedal would go to the floor. Everything appeared ok, no leaks, no fluid loss, just tired flex lines.
PS: i might have good used set in the tickle trunk that i'll throw in with the plastic wiper thingies.

Cool. One of these days we'll manage that covid beer, although the new furbag is a wrench in the ointment


So, I just went outside, tried the brake pedal, completely normal. Pedals firm, right height, there's no fluid drips, nuthin.

This is EXACTLY what it did to me a few years ago. Like creepy deja vu kinda exact.

1/2 hour highway drive without needing brakes, same intersection holy s*** moment with no brakes, get to work coasting to a stop, and a couple hours later the problem is gone. Dafuq??

I'll still get a new mc, because that was ****ed up this morning, and it was just lucky I was at a big merge out lane.

but I'm wondering if that valve did something weird like stick and stop any fluid from going to the front brakes? Not even sure that's possible with the way if functions.

There's really nothing else in the system...and it seems to me, a random blockage would make the pedal firm not drop to the floor.

 

[stevebradford]

Don’t trust that valve!!

 

[seapotato]

Don’t trust that valve!!

I don't

 

[seapotato]

Having nothing to do today but think about this problem ( workin' hard ) I have a new theory...

Water in brake fluid. I used the ebrake this morning when closing the gate, and had to give it a pretty good yank, so it probably moved the brake adjusters.

This made the rear brakes get hot , water became steam and big slug of air symptoms.

Truck sits for a couple hours, things cool off and brakes return.

The front brakes not working either is a bit of flaw with the theory, but maybe that valve whizjammer under the MC dumped pressure.

Even if that is all this was, I'm still going to do some upgrades. Brakes have always been mediocre at best on this truck.

 

[cruiserpilot]

View attachment 2447778
Stock 60 series master that you can have if anyone is driving up there. It worked when I took it out. I'm without wheels for a bit.

I’m heading down and back on Tuesday. Should be heading back around noon or shortly thereafter.
let me know.

 

[seapotato]

I’m heading down and back on Tuesday. Should be heading back around noon or shortly thereafter.
let me know.

Nah all good thanks.

It's time for some upgrades, regardless if my water theory is right .

 

[cruiserpilot]

That coolant stack I’ve found is definitely NPT. Does 1/2” sound about right to you for that
thread size? I’ll pop in to Lordco and grab a brass plug. Will make getting to that hose
clamps on the core connections easier. I’ll look into the better clamps while I’m there.
Is that hose from the block to the heater valve available locally or did you have to special
order that?

 

[seapotato]

That coolant stack I’ve found is definitely NPT. Does 1/2” sound about right to you for that
thread size? I’ll pop in to Lordco and grab a brass plug. Will make getting to that hose
clamps on the core connections easier. I’ll look into the better clamps while I’m there.
Is that hose from the block to the heater valve available locally or did you have to special
order that?

Yeah half seems likely. It'd be my first guess, but I wouldn't swear to it...
Hose was just something I had. A 90* bend heater hose I think is all it was.
Lordco has a pretty good supply of generic hoses with various bends. In normal times they'd let you browse the wall of hoses. Not now I assume.

 

[Toshi38]

I'll go poke around a bit in a while, see if any... fluid has shown up anywhere.

Probably can start by looking on the seat...

Had a similar thing happen on one of my old 60 wagons where the rubber flex lines were so old they would bulge and pedal would go to the floor. Everything appeared ok, no leaks, no fluid loss, just tired flex lines.
PS: i might have good used set in the tickle trunk that i'll throw in with the plastic wiper thingies.

I had exactly the same on my/graham's old dodge when I took it off road... Check for bulges on the front soft lines with someone pushing on the brakes, brake pedel to the floor no missing fluid inner break line burst and could inflate the outer soft part of the line.

 

[seapotato]

Probably can start by looking on the seat...

Haha maybe. Definitely perked up the morning commute.

I had exactly the same on my/graham's old dodge when I took it off road... Check for bulges on the front soft lines with someone pushing on the brakes, brake pedel to the floor no missing fluid inner break line burst and could inflate the outer soft part of the line.

I don't think that problem would come and go though. Drove home last night, normal brakes.

I'm 90% sure some of that Rube Goldberg mousetrap bull**** for the ebrake stuck on, and overheated the rear brake(s) which still shouldn't cause 100%brake loss, but I guess if there was enough moisture in the fluid to flash off it'd make a pretty big bubble.

Seems like I've pumped enough fluid through these brakes that moisture wouldn't be that big a problem but , I'll be giving the mother of all douches today to clean them out.


Had no ebrake when I got home last night, so that gels with the rear dragging theory.

 

[seapotato]

And the winner is....a little nub of plastic on the ebrake cable.

Just enough to fold over and jam inside the jacket, and hold the cable from retracting.

Cable doesn't have a burr, and isn't stiff in the jacket at all either.

My rear wheel cylinders were getting stiff so I threw in some new ones, everything else was good.

I replaced everything not that many years ago, so it's not like it was the standard 30 years of neglect 60 rear brakes


Just one of those things I guess.




Flushed the hell out of the brake lines, because I do think moisture was the issue, although fluid didn't look bad at all. Wasn't even that dirty.

Still going to replace the MC, because the brakes have always been underwhelming on this truck. Think I'll ditch that factory proportioning valve (or whatever the **** that thing is ) and put an adjustable one there.

Was reading some debate about the 80 series MC, larger bore equalling less actual pressure at the brakes unless you also have a more powerful booster.

Have to read some more on the subject.

This clearly happened because I sold the Celica last weekend.

 

[cruiserpilot]

Pair up an 80 booster with 80 master, then you will be good. I’ve needed
mine hard a few times that have impressed me big time.

 

[seapotato]

Pair up an 80 booster with 80 master, then you will be good. I’ve needed
mine hard a few times that have impressed me big time.

Yeah, probably what I'll do, although I think the booster makes the bigger difference than the master.

Just trying to decipher if there's a difference between the 80 booster and the t100 etc. They look identical yet the t100 is a quite a bit cheaper which is either the standard LC price gouge or there's actually a difference. ( just going by rock auto)

Found a decent little summary of the parts out there

Toyota 4x4 Brake Master Cylinder and Brake Booster Specs

Mushy brakes? Worn out brake master? Read here to find out about larger bores, dual diaphragm boosters, and better stopping for big tires on your Toyota.

www.roundforge.com

 

[seapotato]

Found some interesting things on the brakes subject, as I've read more about it than I've ever wanted to.

Turns out 61's and 62's came with a dual diaphragm booster, so I already have that.

Dual diaphragm plus stock size ( ⅞? ) MC explains why the pedal has always felt mushy compared to my 40, no matter how much I bled the system.

Found a pic of a 95 t100 booster next to a 62, considerably larger diameter but how much actual boost you get doesn't seem to be something that has a number value. At least not outside the Toyota engineering lab.

Larger diameter might make a difference, it would make sense, but I think the 1" master will make the 61's feel more like my 40's brakes.

Not sure that'll make it stop any better, but guess we'll see. For now I'm waiting on a Wildwood prop valve, and that alone might make a pretty big difference.

I'll swap out any hoses I haven't gotten to yet while I'm in there. Kinda wanting to be done with brakes.

 

[seapotato]

Bit of a brake fest today.

1" MC and a wilwood prop valve to be rid of the dubious stock one.

I hadn't realized but "Advics" is Aisin. Tried to get the usual Raybestos mc39996 I used on the 40 but the parts drones were having a slow day and couldn't find one with a reservoir, so ****em. Ordered from Rockauto.

I found this little fitment chart...

There's a million part numbers for MC's but in reality, there's bolt pattern, bore size, and whether or not it has residual valves for disk brakes in the rear.

I got sick of reading which was which so I took chart above, and picked the advics one that fit the same.

Used to be, when you bought a MC they came with plastic m10 fittings with barbs and a bit of tubing so you could bench bleed. Not anymore I guess, and I've long since lost the plastic bits.

Also found these. 22" long flex hoses... didn't have to go to Napa for them.

Pedal doesn't feel like I'm stomping on a bag of mashed potatoes anymore.

Haven't had a road test yet, but the prop valve is fully open for bleeding and the brakes definitely have a bit more snap to them.

I'll turn it down a bit once I've experimented a bit.

 

[bcsteel]

Where’d you get the that prop valve ? Rock auto?

 

[seapotato]

Where’d you get the that prop valve ? Rock auto?

Amazon actually. Only issue with it is it's m10 bubble flare not double flare...

If you do the first half of a double flare using the wrong side of the clamp (flat not 45 countersunk) it seems to make a decent bubble flare.

Probably could find the right one too. They sell them everywhere.
The one I put in the 40 was tapped for npt, and came with adapters... thought this would be better but didn't notice the bubble vs double thing.