EM stud thread size? also welder EM stud removal?

[auditude at cox.net]

On 24 Dec 2002 at 8:17, Jim Green wrote:
>
> I wrote:
> >
> > For those running KH intake manifolds, what did you
> > do for the air shrouded injector port?
> > Just block it off, or hook it up to a hose running
> > to(?).
>
> Hook it up to a pre-TB air source, don't block it off
> unless your doing EFI, which you are right?

Right, except post-TB like Javad wrote.  But as for the EFI, I'm not doing that initially.  I have
a Megasquirt kit to put together, which is going to take a while.  My primary goal for the swap
is to get it running and smogged, titled, and registered with the MC-1/MAC11 setup.

<snip>
> > Anyway, regarding re-doing the threads on the head.
> > Should I go ahead and drill out all of
> > them and use a thread repair kit on them?  Or, just
> > do the ones that are buggered?  I'm
> > thinking do them all.
>
> I would leave the good ones alone, just clean them
> out, and helicoil the rest.  Don't use any type of
> glue type thread repair

Any suggestions to clean them out?  I'm not a big fan of using a tap to clean threads, since
they actually remove metal.  I guess I would look for a M8x1.25 thread chaser, or?

> > As for the repair method, I did a spark plug hole
> > with a Time-sert, and had good luck with
> > that.  Anyone want to recommend a Helicoil over a
> > Time-sert?  The difference being that a
> > Time-sert is a solid bushing sort of a thing,
> > threaded on both sides and held in place by the
> > bottom of it being sort of swaged into the head.
> > It's not epoxied in like some other solid
> > inserts.
>
> Let's just say my engine is held together by
> helicoils, I love them.  I've never used a time-sert
> so I can't vouch for them.  I think they are meant for
> through holes where helicoil will not work, like spark
> plug holes.

I can see where a Time-sert would have an advantage over a coil in a hole like for a spark
plug.  I can also see where a coil might have a benefit, since as the bolt or stud is tightened,
the coil actually expands into the metal and bites more.  I don't know if a solid sleeve-type
would expand the same.

That said, Time-sert does offer inserts in the right size for the EM stud.  They offer different
depths, one of which is included in the basic kit.  I guess I could measure the studs threads
that go into the head, unless there is a suggestion for the right depth to get.

I'll probably end up going with Helicoils, since I may need to get them from Napa as Time-
sert is closed for the holidays.

> > I may try the mig-welder method of broken stud
> > removal, if I need to.  Will the bead not stick
> > to the aluminum, just because it's not ferrous and
> > the wire is?  Is that how it works?
>
> It woun't stick, but it may melt it , so you still
> have to be careful.  Honestly , I've always had
> machine shops deal with broken off studs if the heads
> off the engine.  I usually just have them re-surface
> the EM face, head, and remove any broken studs while
> they are in there.

I'm going to get some reverse-drill bits from Harbor Freight and give that a shot.  I could pull
the head off the motor and do it that way too.  I'll do that if this doesn't work out.

Thanks for the answers and comments.

Later,

Ken