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View Full Version : Replaced front hub, BIG SCREW UP...



Agent2006
08-04-2021, 09:58 AM
Hello,

Was getting a squeak-squeak-squeak taking a low speed right turn, varied with speed. We all know what that is = bad front wheel bearing. On Marauders, it is part of the hub assembly. MAJOR pain to get that out, due to corrosion, the hub is steel, the steering knuckle, or anchor is aluminum. So, mega-corrosion. A hub puller failed to budge, 2 days of liquid wrench, MAPP torch, finally had to remove the knuckle and beat the hub out with a 2 lb maul. so, new hub goes in, reinstall everything and installed the two 18 mm head caliper mounting bracket bolts. used a small amount of never seize. Tightened them good and tight. plenty tight.

Car drove fine for 300 miles, then ---bolts must have loosened, because the top bolt actually fell out caliper swung down, hose got kinked then damaged, then NO brake fluid in the front.

The Mercury 2003 workshop manual , 206-03-8 step 5 states : "Remove the bolts and anchor plate. Discard the bolts".

WTH? the bolts are 14 mm diameter steel, coarse thread, not torque to yield....I reused them.

https://www.amazon.com/gp/product/B01E6IP5JW/ref=ppx_yo_dt_b_asin_title_o05 _s00?ie=UTF8&psc=1

Well, here's why. THERE'S LOCKTITE RED on the new bolts, instead of telling you that you need to use loctite. Never used it before on caliper anchors, but....those were always steel bolts into steel brackets and steel knuckles.

EXPANSION RATES ARE GREATER FOR ALUMINUM THAN FOR STEEL, SO THE HOLE GETS WAY BIGGER WHEN HOT, and the bolts becomes loose. no matter how much you cranked down to tighten it. word to the wise...

blazen71
08-04-2021, 10:05 AM
I suggest never using anti seize on brake bolts. A little grease or Loctite will do the trick.

offroadkarter
08-04-2021, 12:09 PM
Almost every bolt, especially tied to brake/suspension/driveline is marked as one time use in the factory service manual.

Agent2006
08-04-2021, 04:27 PM
YES and because of the difference in expansion rates, and the replacements have loctite on them. Then, I looked through some Brand X shop manuals (GM) and they said use "thread locker" on there. Avoiding brand names.

But back to the original idea: USE NEW BOLTS THAT HAVE THREAD LOCKER ON THERE OR ADD THREAD LOCKER /LOCTITE RED TO YOUR EXISTING BOLTS.

Or expect problems...

Turbov6Bryan
08-04-2021, 05:50 PM
I bet you used a torque wrench to the spec, and the bolts were still loose. Two big wrenches or 5 ugga dugga's and those TTY would never have backed out.

Agent2006
08-04-2021, 05:59 PM
No ....OVERTORQUED and still backed out. you CANNOT defeat material expansion rates : lifetime record = 1 zillion - 0. The only other way back in the old days would be to peen the pin by hitting it with a metal punch to jam the threads,

This is why I posted. DON'T MAKE MY SAME MISTAKE!!!!!!!!!!!!!!!

crouse
08-04-2021, 06:58 PM
Loctite Blue. I put that ***** on everything. :)

justbob
08-04-2021, 07:57 PM
https://uploads.tapatalk-cdn.com/20210805/714d93e7caba9242c4e5cadd18949a 00.jpg


Definition of over torque.. My go to tool. If your not careful or an all around spaz you’ll shear them bolts clean in half.


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