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-   -   Frozen on front brake rotor (https://www.rx7club.com/2nd-generation-specific-1986-1992-17/frozen-front-brake-rotor-1125965/)

Nosferatu 05-03-18 05:37 PM

Frozen on front brake rotor
 
My front brake rotor is more or less welded on ...it just won't come loose...pd blaster, heated around the hub,tried a 2 jaw puller, banged and beat on the rotor to try to get it to unseat..short of destroying rotor/hub/bearing by hitting it with major force i'm kind of at a loss for getting it off...anybody run into to this as I'm running out of ideas on how to get it off?

WondrousBread 05-03-18 06:44 PM

This happened to me. Passenger side I used lots of PB Blaster for a week, then was able to take the hub and rotor off, place it so it was sitting on it's lug nuts (on top of a plank), and hammer the back of the rotor in a criss-cross pattern until it fell out. Took about an hour of hammering.

The other side was stuck so badly that I had to take the rotor and hub to a shop and give them a few dollars to press it out. Be careful, if it comes off crooked it may damage the threads and require new lug nuts.

A valuable lesson to be learned here: Always use anti-seize on the hubs before installing the rotor.

TonyD89 05-03-18 08:13 PM

I damaged my hub trying to press the rotor off the hub, be careful and a press is definitely the way to go. Just be sure to use a piece of steel that covers the whole of the hub and not just part of it (my mistake, the bar pushed into the soft aluminum hub).

Best of luck to you.

professionalpyroman 05-03-18 11:48 PM

Please be VERY careful if you use a press! I used a press to do this job about 5 years ago, and I got lucky that the flying shards of iron happened to want to go other directions. It can be the right tool for the job but you need to be cognizant of the magnitude of forces. If the rotors break in the press, it will be in brittle failure. Before you do that please try penetrating fluids and heat and patience as best as you can.

Nosferatu 05-04-18 11:23 AM

thanks all great tips...sounds though I most likely have to pull the hub off and press it...it's pretty much solidified itself on from sitting so many years and rusted badly.when you guys pressed it out which direction did you press it...pressing on the hub or reverse with the press on the rotor? cheers

TonyD89 05-06-18 07:54 AM

I pressed on the front of the hub (disc on back side) and damaged the thin aluminum front diameter of the hub because I used a flat steel bar across the hub instead of a plate that covered the whole diameter. The ram on the press was smaller than the hub diameter. Be careful and patient, bail if you think something's not right, try more heat or penetrant, good luck.

Nosferatu 05-08-18 10:22 AM

thanks for the advice..finally got it off with a makeshift press I cobbled up and 5 ton bottle jack...thought I was going to have to take it somewhere with a real press as it didn't budge even with 5 tons of force and heat...let it sit a couple of days with lots of penetrant..think that was the key over the heat but unfortunately that stuff you have to leave it sit for days to be effective.

NCross 05-09-18 06:58 PM

Good you got it off. I run into this at the shop every now and then. Usually if you put a big 3 ft pry bar on the back side of the rotor and pry between the back of the rotor and knuckle where the caliper bolt holes are and pry with some force towards you while hitting the hub part of the rotor on the front with like a 2 lb sledge it will pop loose. I've had to use an air hammer and heat a few times too. In one rare instance I had one so stuck that the disc part of the rotor separated from the hub part of the rotor!

Penetrating lube is helpful as well.

Mark S 05-10-18 09:25 AM

Galvanic corrosion. This is what happens when you place 2 dissimilar metals in contact with one another. Add heat, water and road salt, and you have a mess.

Aluminum oxide is not affected by penetrating oils... Which is why the PB blaster really did not do much. However, 100% ammonia dissolves aluminum oxide quite well. Used it before with some success on rx7 rotors stuck to hubs. If that fails, then heat, (not too much, as you will trash the aluminum if you get it too hot) and then if all else fails, go with the press.

Also, make sure you put a thin layer of anti-sieze on the hub before you remount the rotor, Dont use too much or it will drip on to the rotor friction surface screwing up your brakes.

pfsantos 05-14-18 02:33 PM

One more vote on the press, using a thick piece to push on the whole hub, and use a scatter shield or large thick sheet of steel to protect you from flying debris.

Couple years ago, used an industrial press, and the rotor broke off in pieces. Crazy shit. Glad we had the steel to deflect the bits.

To those unfamiliar: Aluminum hub + steel rotor + elements (rain/salt/etc.) = Galvanic corrosion = Welded together.

edit: lol repeating other posts.

Nosferatu 05-16-18 09:55 AM

I agree..best thing to do is press them out..wish I did that right off the bat...I didn't pound on them that hard but now have another problem I'm trying to figure out..assembling the brake makes the rotor bind on the top outer part of the caliper casting which is a tight space to begin with..thought it was the new rotor but the old one now does the same thing.runout is good on the hub and new rotor with a dial indicator .001" on the hub and .003" on the rotor/hub assembly... but rotor hub assembly seems slightly canted in relation to the caliper casting and bind on the caliper when bolted down.I can't see bending the spindle,would a bearing cause that? there is no play, I didn't pull the inner bearing as the seal would need to be replaced.so I just pulled the hub off and reinstalled it and seems to have seated itself and had it on and off to reseat , no difference..the only thing I'm leaning on at the moment is the inner bearing...ideas? think I'll start a new thread.

Nosferatu 05-17-18 08:04 PM

pointing towards a bent spindle.


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