Here's my recent published story on this topic: (and don't use
anti sieze!!!)
My Bugeye's front curb weight is supported by two short fulcrum
pins less than 1 inch in diameter. That 1000 lb static load (and
much more dynamic) is carried only by the threaded ends of the two
pins which rotate so very slightly within their outer wishbone
threaded bushings. The fulcrum pin is locked to the swivel axle
and
consequently the wear point is always on the exact same spots on
the male and female mating threads.
Without efficient lubrication, and poorly sealed with cork
gaskets, this assembly can wear quickly. From a safety point of
view, this is often the source of the too typical spridget front
end wobblies, which requiring major repair, is often put off.
Eventually, the assembly becomes impossible to disassemble. The
fulcrum pin refuses to unscrew. Then the swivel axle (which should
benefit from having no wearing surfaces) gets trapped in the
wishbone and the two major suspension components become wedded
together. The owner, usually after a valiant effort with sledge
hammer and torch, then sends the whole mess off to a specialist
overhauler for an exchange item of equal virtue.
A simple five penney improvement is to drill and tap in an extra
two grease fittings. Each new fitting would be opposite to the
one existing, on the fulcrum pin blanking plate. This one hour
modification can easily be carried out in situ, as the Brits would
say.
>From an engineering perspective it is one of the seven wonders of
the world, that this "load bearing thread" concept has through the
decades managed to hold up the front ends of hundreds of thousands
of the Empire's rolling stock. The eighth wonder is that this
1920's design convolution became so well imbedded in the English
system of "shelf engineering", that it escaped the attention of
the Design Office Managers and went on to survive, and possibly
help along, the demise of the Little British Car industry.
Mike L
60A,67E,59Bug
----- Original Message -----
From David Mumford <dmumf at hotmail.com>
To: <nosimport@mailbag.com>; <DLancer7676@cs.com>;
<LColli3554@aol.com>; <spridgets@autox.team.net>
Sent: May 5, 2000 10:43 PM
Subject: Re: Lower Fulcrum pin removal?
> Having just done this, I know what a fun project removing a
fulcrum pin can
> be. My question is about what to do when reinstalling the
fulcrum pin in
> the new or rebuilt a-arm. Is there a way to avoid this problem
in the
> future, or do you just grease the heck out of the pin and
continue to pump
> grease into the fitting at regular intervals? Is Anti-seize
useful? Any
> suggestions would be appreciated.
>
> Dave
> 60 bugeye
>
>
> >From: "Peter C." <nosimport@mailbag.com>
> >Reply-To: "Peter C." <nosimport@mailbag.com>
> >To: DLancer7676@cs.com, LColli3554@aol.com,
spridgets@autox.team.net
> >Subject: Re: Lower Fulcrum pin removal?
> >Date: Fri, 05 May 2000 17:17:08 -0500
> >
> >At 04:38 PM 5/5/2000 , DLancer7676@cs.com wrote:
> > >What Peter said, but at the suggestion of a lister, I ground
a #8 Bolt
> >down
> > >till it was a good tap fit into the screw slot in the
fulcrum, then I was
> > >able to use a socket---gave me a tremendously increased
amount of
> >leverage.
> > >Still wasn't easy.
> > >--David C.
> >
> >What David said, and most cold chisels will accept sockets,
unless you've
> >already used the chisel as a chisel.
> > Peter C.
>
>
>
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