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New caliper installation

I bought some new (rebuilt) calipers for my Econoline van ( 4wh ABS). My question is about disconnecting the banjo bolt, and swapping over the fitting to the new caliper. My Haynes manual says to plug the line immediately to prevent air from getting into the ABS control unit. Other places say to clamp the brake line etc. Any suggestions would be appreciated. Thanks.

I’d clamp the brake line. Needle nose vice grips with rubber tubing slipped over the jaws works fine.

Mechaniker,
I clamped off the line like you said,quickly swapped the fitting over, with 2 new washers on the bolt, and tightened it down. Using my Craftsman 1 man vacuum bleeder kit, I’m getting a lot of air and just a little fluid through the bleeder, and seem to be pumping away with little progress. Does that seem right to you?

Are there supposed to be 2 new washers on the bolt? There should probably be one new washer - a copper sealing washer. If that part didn’t go right then you very well may be sucking air from around the washers.

You can also just gravity bleed - literally just open the bleeder and let gravity push the fluid out (while you keep an eye on the fluid level). It is a very slow process but very easy & effective. I’ll gravity bleed anytime I have other things to keep me busy.

On this vehicle, there are two copper washers because it uses a banjo bolt. Do make sure, however, that one of the old ones isn’t stuck to the hose fitting the banjo bolt goes through, or the banjo bolt itself. Also, from what I have experienced, there is no replacement for the two man brake bleed for removing air.

cigroller,
The new caliper came with 2 copper washers, replacing the 2 that were already on there. Also, despite the fact that I’m getting some fluid through the bleeder, the piston has not moved,even with pretty solid pedal feel, so I take that to mean there is no fluid in the caliper. I will try the gravity method.

Paul S.: “I’m getting a lot of air and just a little fluid through the bleeder, and seem to be pumping away with little progress. Does that seem right to you?”

The fit between the bleeder hose and the brake bleeder screw must be a very close fit. Otherwise when you pump down you will draw air from the space between the hose and the bleeder screw. Some brake bleeder kits have several (about 3) rubber ‘elbows’ that connect the plastic hose to the brake bleeder screw. Use the rubber elbow that has the smallest opening to fit over the bleeder screw.

mark9207: Also, from what I have experienced, there is no replacement for the two man brake bleed for removing air.

I have to agree with that. If there is no wife, g/f around, how about some teenage boys in the neighborhood?

Make sure you got the the right calipers on the right side. If you reversed them, you cannot get all the air out. The bleed screw needs to be at the highest point on the caliper.

I replaced one caliper today on my truck. The box said it was a passenger side, but it turned out to be a drivers side caliper. I had to make a special trip to town to exchange it. At the parts store, they found the passenger side caliper in a drivers side box. Someone probably took them out of the boxes to inspect them and got them mixed up when the returned them.

How I do mine is that I remove the old caliper and hang it off the top of the shock, with the hose stilled attached. Then I mount the new one, get everything torqued. Then I open the bleed valve. The last thing I do is to take the hose off the old caliper and move it right away to the new caliper. No air gets into the hose because gravity is pulling fluid down. when it get hooked up to the new caliper, it immediately starts to fill the caliper and forcing the air out the bleeder.

When fluid starts coming out the caliper, I close the bleeder, pump the brakes to take up the slack in the pads, then I bleed the caliper.

Mechaniker, you were right about the “elbows”. When I held my thumb over the elbow I got no leaks, and the pressure held on the gauge, but when I put the elbows on the bleeder, even the small one, it leaked. Kind of disappointing that the tool doesn’t work well, because I like using it. Anyway, my wife helped me do the 2 person method and it worked in no time. The piston is snugged up nicely to the pads, with a solid pedal. Thanks.

Keith, I like your swap-over system, and will try that on the other side. Thanks.

I left out one small step in my instructions (and also when I did the swap today) and that is to just crack the banjo bolt before taking the caliper mounting bolts out. I used a long breaker bar through the middle of the caliper to hold it while cracking the banjo bolt after the fact, but it would have been a lot easier if I had done it earlier. Just crack it and snug it back so it doesn’t leak while you are changing the caliper out.

Paul S.: “I’m getting a lot of air and just a little fluid through the bleeder, and seem to be pumping away with little progress. Does that seem right to you?”

Have you checked the rubber flex hose leading to the caliper? Those hoses are known to breakdown internally and restrict flow as they age.

Keith, I used your swap-over technique and it worked great!! Much easier and cleaner than the first one I did.

Now I have both calipers installed,and here is the next question…

After I bled the right side, I could see the piston moving back and forth when my wife applied the pedal,and it retracted enough so that there was plenty of freeplay at the rotor, so I could spin it with only a very slight friction at the pads. On the left side there is more constant friction, and much less freeplay. What I would like is complete freeplay at the rotors when the brake pedal is off, but I don’t know if that’s realistic. The new (rebuilt) calipers are from A1 Cardone, and look to be in excellent condition. Any thoughts?

Any thoughts?

Did you replace the rubber hose leading to the caliper?
Old hoses can internally fracture - causing it to act as a one-way valve.

The reason I replaced the caliper (only one) was that it was not retracting enough. It did not match the drivers side. what got me onto it was that I was greasing the wheel bearings and I noticed more wear on the passenger side pads than the drivers side. Also, the wheel bearings were bad on the passenger side.

After replacing the wheel bearings, both sides and getting everything back together, I did a drag test on the brakes. From that I decided to replace that caliper. Now both sides match.

If your brake lines are over ten years old, I would consider changing them, even though my trucks are 14 years old and I haven’t, yet. Then if the calipers are not working equally, I would return the one that isn’t working as it should. If the hoses are old, you could have damaged one when clamping it off.

I avoid A1 Cardone. I have not heard that they have a bad reputation or anything, some people are quite satisfied with them, I just have not been satisfied with them. I’ve had better luck with other brands. Right now, Monroe is my goto with Duralast a close second.

Usually it is the very slight amount of rotor run-out and/or transverse free-play that pushes the pistons very slightly back into the calipers just enough to reduce rotor drag to a minimum. There should be a slight drag.

Compare the left/right brakes by feeling for heat build-up on the two wheels after a short drive. Also look for unequal amounts of brake dust build-up on the wheels.

Also consider JoeMario’s suggestion for internal breakdown of the rubber brake lines. There is an easy way to test if that is the problem or a sticking caliper is the problem. Google dragging brake caliper for more info.

I did get new hoses with the calipers, but was planning to tackle that job later on. My Econoline is a 2001 with only 25k mi on it. I am replacing the brake components in steps, and it’s my first time, so the hose replacement looks like a big deal to me. I was hoping to get the new rotors and calipers resolved first. For now, I will check-out the dragging caliper options, heat build-up etc. and see how it goes. Thanks a lot for your help and good advice.