Hi Alan,
I agree, & 35 ft-lbs is the maximum with "good" threads. I think that
one of the reasons that they loosen is the soft aluminum shock material
under the bolt heads compresses (crushes) slightly & lets the tension
off the bolts. I don't think the bolts really begin to unscrew until the
tension is off. Loctite won't prevent this compression & loss of
tension, just keep the bolts from unscrewing any more after they have
already loosened too much.
I have had very good luck using 3/8 x 1" od hardened steel washers
against the aluminum & 3/8 external tooth star washers under the bolt
heads. Doubt if the star washers are really needed. The hard/wide
washers spread the load out more over the aluminum & prevent compressing
(sinking into it) so much. I suspect that at 35 ft-lbs, there is only
about .002" or less of bolt stretch. So it doesn't take very much sink
into the aluminum to let things loose.
Another thing that I think helps. My shocks came from World Wide Auto
Parts with steel bushings in the shock mount holes. The bushings are
pressed into the aluminum & are a snug fit on the 3/8" mounting bolts.
They were probably bushed to repair wallowed out holes on the cores that
Peter used. In any event, this prevents any lateral movement of the
shocks which could help compress the aluminum. My factory original
shocks have a rather loose fit on the bolts but no evidence of
wallowing. They were just originally made loose on the bolts.
I still check them, but haven't found anything loose on the front yet.
Aside: I think that solid lateral location (in relation to the bolts)
on the rear shocks via snug steel bushings helps there also. Too bad
they don't have room for a very large hardened washer.
Dave Russell
BN2
Blue One Hundred wrote:
> Tom -
>
> I know what you are saying, but if Niel uses loctite
> on his bolts, breaking the captive nuts loose WILL be
> a problem!! Just torque the bolts down every 5,000
> miles or so (10 minutes of work, can do it wothout
> jacking the car up)... 25-35 ft-lbs is enough!
>
> Cheers,
>
> Alan
>
> '53 BN1 '64 BJ8
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