Stuck strut bolts and factory "thread lock"

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crw

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My '98 BMW desperately needs new struts. I've bought the new units, but am having a terrible time with the two bolts that attach the strut to the wheel hub. They are not rusted to any degree, but incredibly hard to turn.

I've heated the area with a propane torch, used a breaker bar and a mallet, and was able to get one bolt out but not the other one. When I got the first bolt out, it had a white substance on it which I assume to be some sort of factory "thread lock". Also, the bolt did not break free, but remained super difficult to move until it was more than half the way out.

Any ideas? Does PB Plaster work in cases like this? If I were on a lift, this wouldn't be so hard. The shop wants $240 just to install my struts...
 
PB Blaster might help - give it time to work. But whatever you do, don't round the head of the bolt. Use quality tools and technique. Do you have a flank type socket........one that contacts the flats, not the points? Breaker bar with that should work.
 
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Is the second bolt turning (as in you need a wrench on both sides?
How long is your breaker bar?
Do you have an impact wrench?

I removed a strut on my 1995 Ford Escort yesterday, and it was quite easy. I used a breaker bar to turn the nut a little, then my electric impact wrench to get the nut off - quickly. Then I removed the bolt using a regular ratchet (impact hammer wouldn't fit there).

If it matters, this is the impact wrench I used:
http://www.harborfreight.com/12-electric-impact-wrench-68099.html

PB Blaster does help, I use it a lot. The only problem with the stuff is that it often makes it easy for your wrench to slip off as well.
 
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Maybe I need a longer breaker bar and get it higher off the ground, to allow more movement. I do not have an impact wrench.

One thing about those bolts, the quality is incredible. Typical BMW. I don't think they could be rounded off.
 
Oh, by the way, I even tried using a floor jack to raise the breaker bar. I still could not get it to budge before the attempt failed because the plane in which the bar is moving is offset by the socket length. If I had an 18mm wrench, and some sort of extension... so the bolt head is in the plane of movement...
 
Originally Posted By: user52165
Do you have a flank type socket........one that contacts the flats, not the points? Breaker bar with that should work.


I have a six-point socket (and a 12-point), I assume this is something other than these?
 
Originally Posted By: crw
Oh, by the way, I even tried using a floor jack to raise the breaker bar. I still could not get it to budge before the attempt failed because the plane in which the bar is moving is offset by the socket length. If I had an 18mm wrench, and some sort of extension... so the bolt head is in the plane of movement...


Get and use the right tool. Buying it will be cheaper than paying someone to do it.

BTW - any bolt can be rounded. Using Redneck methods will do it.
 
Originally Posted By: crw
Originally Posted By: user52165
Do you have a flank type socket........one that contacts the flats, not the points? Breaker bar with that should work.


I have a six-point socket (and a 12-point), I assume this is something other than these?


See attached:

http://www.sccoa.com/forums/showthread.php?t=79582

Flank drive is a Snap On name and idea, but has become a generic term like Scotch tape or Kleenx. Everyone makes them now, even HF.

6 point is better whenever possible.
 
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Well, at Harbor Freight I found a T-Drive (breaker bar with two ends) that *should* work. Now I can apply torque to both ends and have no forces that want to pull the socket away from the bolt head. Think of the tool that one uses to remove lug nuts, (sans impact wrench) this is much the same.

As for the bolt, it's simply a bolt that threads into the wheel hub. There is no nut.
 
Originally Posted By: crw
And if that doesn't work, I'll go buy the impact wrench, lol...

Buy the impact wrench anyway. Provided you're using it on fasteners where you have lots of access-room, an electric is amazingly effective. I have a DeWalt DW293, a 7.5A unit capable of 325 ft-lbs of torque.
It has NEVER failed to remove ANY bolt I have EVER tried it on. That includes suspension, crank pulley, wheel nut, FWD/4WD axle nut, you name it.

Once you have one, you'll wonder how you ever got along without it. Jobs that formerly filled you with dread will become trivial.
 
Those bolts will come off in five seconds with an impact wrench. And you get to enjoy the sickly sweet aroma of the threadlocker breaking free.

If you don't want to buy one, check the local tool rental places; some even rent them (the electric ones).

With seven cars to maintain, it would be a worthwhile purchase.

Once those bolts are off, getting the strut out is easy. No need to disassemble anything else like the manuals say. Just use the jack, or something else to keep the hub assembly propped up after you manipulate the strut out of the wheel well.
 
An impact may be the only way. The ones on my Prius are torqued to 177 ft-lbs from the factory; a second of blasting knocked them loose.
 
Sometimes, the impact action seems to be far more effective than outright constant high torque applied by a large breaker bar.

Perhaps it is the impact force elastically deforming the fastener for a split second and continues that action, this breaks the bond that causes fasteners to stick.
 
BTW, those bolts, as well as the rest of the (lock) nuts are considered one-time use if you go by the book.

The three bottom fasteners are only torqued to ~79 ft-lbs, so they are doable by hand, excluding extenuating circumstances.
 
Originally Posted By: chrome
Sometimes, the impact action seems to be far more effective than outright constant high torque applied by a large breaker bar.

Perhaps it is the impact force elastically deforming the fastener for a split second and continues that action, this breaks the bond that causes fasteners to stick.


^This. I just read a thread over at Garage Journal where pro mechanics are having GREAT success removing spark plugs from aluminum heads by zapping them out with 3/8" impact wrenches, even the troublesome Ford Trucks with three engine threads (that break).

The impact is proving much better than easing them in/out with a hand ratchet.

Something about the impact action is much more effective than any long breaker bar/turning action.

But, the 79 ft. lb. thing is confusing. That's less than wheel nuts. And, if the threadlock is the more potent type, you might need more heat than a propane torch will give to a large casting....maybe?
 
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