Rear brake rotor stuck on the hub - help
My right rear caliper kindly deposited DOT 3 on my garage floor until the rear reservoir in the master cyliner was empty. The calipers are original and at least the rear two have been bored and sleeved with stainless steel by a previous owner. The front two most likey have been as well, but I haven't gotten to them yet. I figure that if they have been rebuilt once then I should just replace them. Can/should caliper piston bores be successfully re-re-sleeved?
But the real problem...
After removing the right rear caliper and disconnecting the emergency brake cable the rotor should be wobbly and loose and slide right off with finger-tip pressure (previous owner drilled the rivets out). But not this one - it's stuck solid.
Does anyone have any ideas (other than a bigger hammer) how to get the rotor off? So far I've whacked it with a rubber mallet, and soaked it with penetrating oil. Tonight I think I'm going to try putting some heat to it.
Has anybody ever pulled a stuck rotor off with a large wheel/gear puller? I'll go rent/buy one big enough if I know it'll work, but I don't want to put too much pressure where it doesn't belong and mess up my bearings.
I have no idea what could be holding that rotor on there so tightly. I'm hoping it's just rusted on there and that Bubba didn't try to JB weld the rotors to the hubs after drilling the rivets out - but I don't think that's the case because the left side slid right off with no problems at all.
Try an air hammer with a blunt tip on it, hold constant pressure on it while roving it around on the flat surface between the studs.
get some PB Blaster....if you havent already...much better for rust than wd-40....or try kerosene ...the biggest culprit is rust ...the rotor has very little room for anything between the hub and the rotor...you need a wire brush , emery cloth...a wire wheel on a du-more or drill and get to work on the hub...you need to get the hub as clean as possible before you can slide the rotor off of it...all the way around it, not just the top...its gonna take time and muscle....being in the corp im sure you have plenty of that!
keep at it.. a few whacks when you have it clean and it will come off.shouldnt need a puller....may do more damage to the hub...this is just my opinion and im sure there will be more to follow.
Thanks for your service to this great land we proudly call AMERICA!
Well first off someone(s) has been in there so anything is possible. The parking shoes are probably holding you up. If someone drilled the rivets out then they probably tried to replace the parking shoes. You might be able to compress the shoes enough to remove the rotor otherwise you're going to have to hammer those babies off.
As for the calipers, split them in half and remove the outer seal and the pistons. Clean them with clean brake fluid and look at the bores. they should be shiney smooth any ridges and you should replace them. Most caliper houses don't want sleeved cores because of the unknown practices used to machine then before. I've seen sleeved calipers that weren't sleeved with SS but steel instead. Most of the big shops stamp their logo or initials in them too so look for that.
Replace the hoses and front copper washers. Check runout,keep it under .005" but under .003" is better. Over .005 fix the problem.
Thanks for the advice.
Coupeman - how can I compress the parking brake shoes with the rotor still covering them? The parking brake works correctly and I disconnected the cable so I wouldn't think the shoes are putting any pressure on the drum - but like you said - anything is possible.
vettedude73 - you're right, I'm no stranger to elbow grease. I'll clean up the seam between the hub and rotor as much as I can, but there's not much of the hub showing. I'm using some store brand penetrating oil - is PB Blaster that much better and worth going after? I don't have any kerosene laying around - but I do have some pretty good gun cleaning solvents used for removing copper and lead fouling from rifle bores - maybe I'll give that a shot.
69autoXr - air tools: now I know what I want for Christmas!
I'll let you know how it goes.
PB Blaster is a great addition to any garages shelf..only a few bucks...good luck pal.
on regular brakes the shoes can easily stick the drum on, I havent done my brakes yet so i'll ask the question,do the rear brake shoes have adjusters like regular brakes or do they adjust somehow on the cable??the brakes can be worn into grooves on the drum,
I'll keep an eye on this thread as mine are bleeding on my floor too, not as much though. mike
The rear parking brakes are, in fact, a small drum brake setup. Yes they can be adjusted if not rust frozen. The rear rotors have 2 acceess holes they are not in the bolt pattern of the wheel studs or rivet holes.There is a "star" wheel in the 6 o'clock position. Rotate the rotor until you can see the wheel through the hole and use a thin blade screwdriver to adjust them. Once the caliper and rivets are off there is nothing else holding the rotor on except rust or expanded brake shoes. You might have rust build up at the spindle flange where the rotor center hole is. It''s a good idea to mark the relationship between the rotor and a stud so you can put the rotor back on in the same position. Watch out too if you think you'll be able to resolve runout issues by turning the rotor on a brake lathe. the spindle and rotor were riveted together then turned as one. Tuening them independly will not correct the problem and only cause you to machine away your rotor,which only has .035 max thickness before discard spec.
Coupeman Has the Answer
Unless your rear brake rotor is 100% froozen in place and has no wiggle room when you try to move it, chances are that your parking brake shoes are still too expanded to allow removal of the rotor/drum. Even with the parking brake lever disconnected, the adjustable star mechanism inside the brake drum is still keeping the brake shoes in an expanded position. Unless you stick a screwdriver in the drum hole and adjust the star mechanism to retract the brake shoes, your drum may remain stuck. The reason for this is that over time, wear inside the drum takes place that creates a ridge on the inside edge of the brake drum. If the brake shoes are not retracted enough they get caught on this ridge.
If your brake drum/rotor is 100% struck, chances are that you may have other problems going on inside. Nevertheless, retracting the brake shoes by adjusting the star mechanism might help you in the 100% stuck situation by providing you more clearance between brake shoe and drum.
You did remember to release the "Brake Drum Removal Pin" before you started this project?
..... just kidding on the last comment.
Last night I adjusted the star wheel to retract the parking brake pads as far as they will go.
I employed the assistance of Mr. PB Blaster, Mr. Sandpaper, Mr. Wire Brush, and Mr. Estwing in the form of my 3 lb sledge. I'm still hesitant to whack a cast iron rotor with a hammer, but I gave it a couple of pretty good smacks. End result wasn't much, although progress was made. Grasping the rotor with both hands I can wiggle it. We're talking about 1/32 or maybe 1/16th of an inch, but at least it's not completely frozen solid anymore and I know there's room for the liquid to get in there and work.
I gave it a good amount of PB Blaster so I'm curious to see what happens when I get back to it tonight. Step by step...
Thanks for working me through this one guys.
One other thing, are the rivets drilled through completely? Maybe someone tried and gave up and the there's still a rivet holding it in?
You mentioned "heat"...have you tried expanding the drum area of the rotor by applying the pinpoint flame of a propane torch, both around the spindle area and around the outside "shoe" area? I have seen this work miracles when the strongest gear pullers wouldn't budge the item...used it myself many times when pulling boat props of of shafts...they really weld themselves on after a while in salt water! Just make sure all the "flammables" are cleaned up, and have an ABC extinguisher at the ready!!!
If you can wiggle it at all, it's the brake shoes hanging up on the ridge in the brake drum. Rust would freeze it solid. Are you sure that you adjusted the brake drum star in the correct direction?
Each side is goofy. If you adjust the wrong direction you will lock the drum in place and only be able to wiggle the entire assembly a little bit - just as you describe.
Also, in the future, never spray lubricants on or near brake shoes. This can cause swelling of the brake shoe material and cause binding.
I think the whole street heard me shout for joy when I got the rotor off today after work!! Too bad "PB Blaster" won't fit on a SC license plate. Vettedude73 - I owe you one for that suggestion. I think I'm going to buy stock in that company.
Thanks for all the help. It turns out that all the rivets were completely drilled out, and I did indeed adjust the star wheel in the correct direction. I was about to pull out the torch, but a little bit of patience, elbow grease, almost a whole can of PB Blaster over a 48 hour period, and of course my friend the 3 lb hammer did the trick. Nothing more than rust holding it on.
You were right Roy, it was rusted solid when I started, but after a day of soaking it I could move it a little bit, and after the solvent had a chance to work for a second day, it was enough that I could get it hammered loose.
I never knew that lubricants would swell brake pad material. I'm happy that I didn't run into that problem. Projects can be hard enough without unknowingly contributing to the problem.
PS - in case y'all haven't heard, anything you order from Ecklers' web site this Sat and Sunday (Dec 13 and 14) is 10% off.
Hey, fantastic! "Love it when a plan comes together"!!!
Thanks for the tip on Ecklers...I need to get a few items for the old '86 coupe...sounds like now is the time!!!
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