Have my rubber brake hoses collapsed?

[kaysboat]

I had the front brakes lock up on me on y 1980 Chevy C10 (does not have power brakes, disk on the front, drum on the back). I determined it was a seized caliper (front wheel got very hot, truck pulled slightly to the right and when jacked up, I could hardly sprin the wheel). I decided to do a complete front brake job for good measure. Replaced both calipers, pads, rotors and bearings. Once I was able to loosen seized caliper bolts (HUGE pain) everything went fairly smooth until I went to bleed the brakes. I loosed the bleeder screw, ensured there was enough fluid in the reservoir, and started. However, when I push down on the peddal, it doesn't go to the floor like it should when bleeding new calipers. It's as if I hadn't changed them. Also, the rotor still spins freely. Additionally, when I removed the old caliper, hardly any fluid drained/dripped out of the hose. I ensured the hose to caliper bolt was clean, installed a new copper washer between the caliper and hose end, and yes I removed the plug in the new caliper.

Although I've never had this issue when doing brakes before, from reading a bunch of forums on here, it seems like my rubber brake hose may have collapsed (possibly from moving it around a bit when removing/installing the caliper. I think the hoses are original), but any thoughts?

if so, how hard are those to replace? Where is the other end (non caliper end)? I had a quick look, but couldn't really tell.

Thanks for any thoughts/advice.

[hatzie]

If they're original they are 39 years old. I'd change them.
You need to center the combination valve shuttle.

The service manual mentions Kent Moore tool J-23709 It's the Kent Moore SPX tool for keeping the combination valve pin depressed. The pin is under the rubber cap opposite the rear brake line fitting.
J-23709 is literally a piece of sheet metal with a 90° bend at one end.. The slot in the long leg fits under the combination valve mounting bolt. The bendy part pushes the pin down and keeps it from pushing out. You remove it after you have the brakes bled out.

You can fab your own with some metal and a vise. Bloody simple little tool.

This picture is with the pressure bleeder adapter cap but it gives a pretty good idear of what the J-23709 tool should look like installed.

[old Rusty C10]

ive had more brake hoses go bad than calipers in my day but when one goes I change the other for good measure... I figure safety is better than stitches

[kaysboat]

I had a look for the combination valve to try that, but I don't seem to have one on my truck (at least not in the same location as the shop manual pictures posed above). I have the two steel brake lines coming out of the bottom of the master cylinder and then they run forwards to the front cross member. (See attached picture).

Would the combination valve be anywhere else except right under the master cylinder/on the firewall somewhere? Or, would I even have one?

I'm going to try replacing the rubber hoses (if nothing else, just for good measure). Likely won't be able to get to it until Tuesday after work. If it's not that, then I'm a bit confused (more so than already).

[hatzie]

Originally Posted by kaysboat

I had a look for the combination valve to try that, but I don't seem to have one on my truck (at least not in the same location as the shop manual pictures posed above). I have the two steel brake lines coming out of the bottom of the master cylinder and then they run forwards to the front cross member. (See attached picture).

Would the combination valve be anywhere else except right under the master cylinder/on the firewall somewhere? Or, would I even have one?

I'm going to try replacing the rubber hoses (if nothing else, just for good measure). Likely won't be able to get to it until Tuesday after work. If it's not that, then I'm a bit confused (more so than already).

You have one. Look on the frame crossmember almost under the radiator on the LH (driver) side of the truck. Follow the brake lines from the Master Cylinder to it.

The picture is from a Corvette or Chevelle Service manual. I used it because it showed clearly where the bendy piece of sheet metal goes.

[kaysboat]

Ah I see. I don't mean to ask stupid questions, but how to you reset the pin? I had a look through the service manual, but it doesn't really say (talked about it a bit with pressure bleeding).

I assume you back the nut off enough to insert the tool, bleed the brakes, then remove the tool and tighten the nut. Is that correct?

However the shop manual also spoke about the brake warning light coming on if there is an issue with a loss of pressure in the brakes (and the combination valve being activated). This hasn't happened to me (and I know the bulb works because it lights every time the parking brake is engaged), but I also don't think I've lost pressure in the front brakes (as there is no leak). Is this normal, or is my combination valve broken as well?

Thanks for the responses so far. I shouldn't have any more questions after this (although I didn't think I'd have any questions doing a simple brake job either).

[hatzie]

It might or might not light up. Depends on how hard you hit the pedal with the bleeders open.
If you're worried ground the wire that's attached to the combination valve to test the wiring. The BRAKE lamp lights when that wire is grounded.

Yup. You loosen the mounting bolt/nut and slide the slot around the bolt and slide the tang up tight to the combination valve to keep the warning switch shuttle from moving as you bleed the brakes.

[kaysboat]

Should be the last question.

Have everything installed, and am going to try resetting the pin. However, those tools are hard to find (impossible locally) and BLOODY expensive on line.

Does anyone know the width and length of the slit so I can make my own out of a piece of metal?

[hatzie]

I wouldn't pay $20 for one either...

It doesn't have to be exact. You know where it goes and what it does.
Measure the mounting bolt diameter. Slightly more is the width of the slot.
Then make sure the slot is slightly maybe 1/4" longer than the distance from the bolt head to the pin end of the combination valve with the tool installed.