The silicone was just a build up from what got on the threads as it passed
through the hole during installation. What happened is that there have been
probably 5 installations, each one leaving a bit more residue.I think that
when each time the bolt was removed, what ever silicone that was on it was
left in the hole. Hence the build up over the years. Anyhow, it seems to be
fine, there were enough threads left to get a good bite.
Thanks for the info.
Todd Barker
----- Original Message -----
From: Brian Hollands <bholland@hayes.ds.adp.com>
To: Todd Barker <barkert@centinela.k12.ca.us>
Cc: Datsun Roadster Mailing list <datsun-roadsters@autox.team.net>
Sent: Friday, October 26, 2001 8:56 AM
Subject: RE: Broken Water Pump Bolt hole x-mac-creator="4D4F5353"
> BMW's factory manuals caution strongly about oil in bolt holes -
> particularly head bolt holes - for the same reason. Oil, being
> non-compressible, is well known as a cause of block fractures. If you
coat
> bolts with a lubricant before installing them make sure you don't use any
> excess, just enough to lightly coat the threads. I'm a little surprised
> that silicone did that as it is compressible but if there's too much...
>
> Brian '69 2000
> Tampa, FL
> http://web.tampabay.rr.com/oilleak/
>
>
> -----Original Message-----
> A strange thing happened to me tonight when I was putting a new water
> pump on my U20. When I tightened the bolt that holds the water pump to
> the timing cover/block, the part of the block that forms the bolt hole
> split off. The bolt was not too tight nor too long. When I took it off,
> it came out fine. After inspecting it more closely, I have determined
> that there was a buildup of silicone (left over from some other time) in
> the back of the bolt hole. When I put the bolt in and started
> tightening, the pressure blew out the side of of the bolt hole.
///
/// datsun-roadsters@autox.team.net mailing list
///
|