Mechanics

BLEEDING THE BRAKE SYSTEM

1992 Ford F-150 • 236,000 miles

I had the passenger front brake line burst on me a few days ago. I went today and got a new a line and installed it. Everything went fairly easily. So, since it had never been done, decided to change the brake fluid at the same time. I have a manual vacuum brake bleeding system. One of those you connect and pump by hand. Started at the passenger rear and pumped until I saw nice clear fluid coming through. Same on driver rear. I'm now at the one where I replaced the line and I can get nothing to come through the bleeder screw. I took the screw all the way out and checked it to make sure the pathway was clear and it was. I've tried using the vacuum pump and the old 2-man bleeding method, but nothing so far. Just to check, I disconnected the line at the caliper and there is nice clear fluid coming out of there, so I believe fluid is getting to the line and I see no leaks.

Is it possible something is wrong with the caliper, which is preventing me from bleeding it? When I removed the bleeder screw a second time, just to make sure, it was completely dry at the bottom.
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MStrawder
June 17, 2013.




Try to put eh caliper bleeder screw back in then pump the system up to 20 psi then crack the line at top of hose to see if fluid is coming through. The hose may be yor problem going to caliper. If it is replace both front hoses.

Hmac300
Jun 17, 2013.
I've put the bleeder screw back in and tried operating the vacuum again. Just a hand pump connected to a reservoir and then the bleeder screw. I went and unbolted the line from the caliper again and sure enough, there's some fluid getting in there as it ran out of the line. Not as much as I would have expected though. It just doesn't seem like the caliper is getting filled with fluid.
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Tiny
MStrawder
Jun 17, 2013.
Reread my first reply probably your hoses aren't any good. Or the caliper is frozen

Hmac300
Jun 17, 2013.
I'm leaning towards the caliper. Read what you said about the hose, so I decided to unbolt it, submerge it in new fluid and give it a few pumps. Air bubbles shot out. When they were gone, I bolted it back to the caliper and I suddenly had pedal pressure. Of course that only lasted until I started the truck and tried to push the pedal. So that hose at least (which I replaced today) is capable of pushing fluid through. So if the caliper is frozen, it would be impossible to prime it essentially?

Tiny
MStrawder
Jun 17, 2013.
Pretty much cause it'snot gonna move the only other thing you could try would be to take bleeder screw out an dlet it gravity bleed for about an hour and see if it will bleed then

Hmac300
Jun 17, 2013.
Ok, I feel less inept now. I've always hated bleeding brakes. Would the frozen caliper cause that brake line to burst as well? I had noticed in the last week or so that when I applied the brakes, there was a slight pull to the right, so the caliper being bad does make some sense.

Tiny
MStrawder
Jun 17, 2013.
No the truck being 22yrs old has more to do with it make sure to replace other side as well

Hmac300
Jun 17, 2013.
Will do. Going to replace the caliper tomorrow and I'll change the line while I'm at it since I wanted to replace the fluid anyway.

Tiny
MStrawder
Jun 17, 2013.
Replace both calipers and hoses not just one

Hmac300
Jun 18, 2013.

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