I'm installing new ball joints on our 93. I bought Moog figuring that Carquest sells them all over the country and Swedish Engineering uses them all the time. Swedish Engineering had them delivered with great service. The ball joints look great, and were made in Spain. Anyway, I mounted one of them last night in its housing, the housing that is fastened to the bottom of the strut tube with four bolts. I used an 18mm flange locknut (Volvo part number 969317) and two drops of blue threadlocker (Carquest Brand). I cleaned the stud and the nut threads with carb cleaner first and made sure it was all dry. Then I torqued the nut to 45 pounds as specified by the Volvo green book. I left it for 24 hours. Today I changed my mind when I realized I hadn't used the exact locking nut that Volvo specified. (Important component here.) So I went out to the garage and removed the nut, which had been torqued with threadlocker 24 hours before. To my surprise, the nut came off with very little pressure. I set my torque wrench at 45 pounds as an experiment, but it took far less pressure to get the nut off. I figured it would be take more pressure with the cured threadlocker, not less. What am I missing here?
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Thanks for all the help. DougC. 1981 242 Brick Off Blocks, Turbo bars and wheels, M46. 1990 245, auto, 113k. 1993 245, M47, 154k.

Don't forget that if its cold, the loctite takes a lot longer to cure.... Go with the red as someone else mentioned. Loctite does have a cure time that is dependant on temperature, regardless of blue or red!

jorrell

The temperature in the garage was about 45 degrees or more. The garage shares two walls with our heated house. Outside temp stayed above freezing the whole time. Yesterday's high outside was 48. Just for fun, I'm going to run some tests with the blue and red on some extra nuts and bolts. On the package of red it says the connection must be heated to 500 degrees F before it will come apart. Those who have had experience with red: Is this really true? Do you think an impact wrench would break it loose without the heat? I guess if I use red with a good locking nut, at least I wouldn't have to worry about the joint ever falling apart while my wife is driving down the interstate. The worst that would happen is that someone 100k from now would need to go buy a new ball joint housing if they could not remove the nut.
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Thanks for all the help. DougC. 1981 242 Brick Off Blocks, Turbo bars and wheels, M46. 1990 245, auto, 113k. 1993 245, M47, 154k.

I think they mean it is good to 500°. You can probably break it loose but
it will take quite a bit of torque. Remember it is a polymer, not a metal.
You are probably talking about a strength of 3000 psi or so where the metal
is in the range of 60-150,000 psi or more. Assuming 18mm diameter and 18 mm
length of engagement that is roughly a square inch of engagement x 3000 psi
of shear strength. Assuming a 9mm distance from center (~0.350) and a wrench
20" long you have a mechanical advantage of about 57:1 so a 55# pull should
shear it. No damaging impact tool needed.(Note that this does not consider the
breakout torque from the clamping force of the joint.)
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George Downs Bartlesville, Heart of the USA!

The Permatex Red Threadlocker package actually says, "Cured product must be heated to 500 degrees F before parts will separate." Has anyone found this to be essentially true?
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Thanks for all the help. DougC. 1981 242 Brick Off Blocks, Turbo bars and wheels, M46. 1990 245, auto, 113k. 1993 245, M47, 154k.

Thanks. Your mention "damaging impact tool." What's your feeling on when an impact air wrench is the correct tool to use? Some people seem to use them indiscriminately, while others much more judiciously. I'm trying to develop sound shop practices.
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Thanks for all the help. DougC. 1981 242 Brick Off Blocks, Turbo bars and wheels, M46. 1990 245, auto, 113k. 1993 245, M47, 154k.

You may be opening a real can of worms here. My opinion is that there are many times when an impact tool is less likely to cause damage on disassembly of parts. I've sheared bolts far more often using a big breaker bar than with a 1/2" air impact gun. This seems to hold particularly true with rusted, seized fasteners where impact is key to breaking them loose vs. just twisting them off. I certainly hesitate to use impact to loosen sequenced fasteners like head bolts - then again those are rarely seized, unless it's a 960...

For tightening however, be judicious in your use of impact - an impact gun can easily stretch fasteners such that their shear strength is greatly diminished (I'm no metallurgist so forgive me if I should be referring instead to tensile strength or something else). Overtighten the control arm rear bushing bucket bolts, for example, and a big pothole could be enough to snap them.

The common middle ground seems to be that most experienced mechanics very rarely use torque wrenches, perhaps only on head bolts... They've got enough of a feel for the impact gun to know how much is enough, and go with it. Personally I'll use the impact gun for disassembling just about anything, and set low to snug down those pesky locknuts on balljoints and tie-rod ends, then I go back over it with a torque wrench (or just grab a ratchet and give a final tug on it).
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Chris, Dartmouth NS Canada 70 M-B 280SE, 83 245DL, 84 244 turbo, 90 780 turbo, 92 VW Golf, 90 740 Rex/Regina

This is probably a worthwhile can of worms to open. I'll post a new thread with the right title. Those of us who are trying to establish good shop procedures should know this stuff. Thanks for the info.
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Thanks for all the help. DougC. 1981 242 Brick Off Blocks, Turbo bars and wheels, M46. 1990 245, auto, 113k. 1993 245, M47, 154k.

Loctite Blue secures the threads enough to prevent vibration-driven loosening, but allows easy removal. Loctite Red is much stronger and allows a near-permanent bond. It is much tougher to remove. For that application, you might consider Red. For most others, Blue is fine.
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See the 700/900 FAQ under 'Select Link' button on the top right.