Re: Stripped inlet manifold stud

[drubie@macquarie.com.au (David Rubie)]

Andrew Annakin <Andrew.Annakin@wrc.govt.nz> wrote:

> Greetings.
> 
> I'm replacing the intake manifold on my 2L Spider. I've discovered that
> one of the centre studs had a non standard nut forced onto a stripped
> thread. These are pretty skinny studs so I think I need to remove and
> replace it. 
> 
> *	What's a good, back-yard, way to remove studs?
> 
You might not need to replace it if you're careful.  If you run
a good nut over the stud it might become usable again.

The first, easiest way to remove a stud that still has useable
thread on it is to "double nut" it.  I.e. run two nuts down the
stud, then tighten the bottom nut snugly against the top nut
in an anti-clockwise direction.  Eventually, the bottom nut
will be so tight that any turning action will force the stud
to turn.  Usually this requires two 13mm spanners.  I don't
recommend an adjustable spanner for this job.

However, if you haven't got any useable thread, you
need to get fairly serious.

There is only one real way to remove busted or threadless
studs, and that's with an
"easy out".  They are a reverse threaded doohicky that you need
to drill a hole in the stud to insert.  Once inserted, you
turn them and they turn the stud out for you.  They can be
tricky with small studs however.  My recommendation is that
if you can't turn the stud out with vice-grips, then attempt to
drill a hole in the end of it and get an easy out in there.
Trouble is, with studs, the drill bit small enough to drill
a stud is typically small enough to snap off in the stud,
so you have to be extremely careful.  There is nothing worse
than attempting to remove your drill bit from your wrecked
stud.  I know this, because just this week I managed to
destroy the stud that holds the distributor on my Alfetta GTV.
Try putting as many nuts on the stud as you can so that an errant
drill can't attack your precious cylinder head.

I tried filing some flats on the stud I broke to put a spanner on it,
but only managed to break off part of the top of the stud.  I
tried hack-sawing a slot in the stud for a screwdriver, but
the metal was too soft and the screwdriver merely broke one
side off what was left.  It was a  pretty sad mess.  Then
I got angry...

...After I had broken a drill bit off in the stud, I had a look
in the Yellow Pages and called a thread fixing mobile van guy who
came out (minimum call - $150AUD) and broke the stud off flush
with the timing case, then using a "diamond drill" drilled my broken
drill bit out enough to get his own easy out into the remains.
This came out in a flash.  He then drilled the hole out further
and put a nice steel insert into the hole, so that next time I
screwed it up he could fix it faster without destroying my
timing case.  Very nice bloke.  Well worth the money too, he
was great to watch, plus he had a bunch of very expensive tools
I could never contemplate buying for the money I paid him.

My advice, after that bit of waffle, is if you can't double nut
the stud out and you can't get an easy
out into the stud cleanly, get a professional to fix it.  They
can put a new stud in there to the correct tightness without
any trouble while you are there.  The mobile service might not
be available where you are though.  If you were really paranoid,
pull the cylinder head and take it somewhere, get the valves ground
while you are at it (plus new valve guide seals etc...)



[deleted]
> 
> *	I assume the protective coating side of the manifold gasket faces the
> block, paper side to the manifold?

From memory, these things can only go on one way, being asymmetrical.

I always use gasket goo / Permatex on the manifold gaskets because there
is water circulating around in there.  Actually, on this engine I used
Hylomar.  It's is brilliant stuff IMHO, much better than Permatex (although
much more expensive too).  I built an entire engine (sump to thermostat
housing) with a single tube and there is still some left with no sign
of oil or water leaks so far.

[deleted]

dave.