Also of you mess up the hole and keep the center,they make a step stud
4/6 6/8  8/10 . I've used these before with great results. I read this
thread with more than casual interest. As I just got through remove all off
the exhaust of off of my 2.1 .The rust was so bad that the flanges were half
size.and the nuts had no shape. I carefully ground the nuts down to the stud
or until I started to see threads and the beat the nut off with a chisel. I
am happy to say that that besides cutting thermosta housing with the Sawzall
I have no broken studs and will not have to remove the engine to replace my
exhaust.

Stacy

On Tue, Mar 18, 2008 at 8:55 PM, aatransaxle <daryl@aatransaxle.com> wrote:

> Its a real PITA to get them drilled straight..Even after 30 yrs of cussing
> the job, I still don't always get it right..
> Some machine shops have whats called an EDM which eats out the stud or tap
> or drill electrically, but is only good if the head is off. My
> neighborhood
> machine shop has one when taps break during CNC machining. Otherwise..
> Getting a flat surface is critical to center punch and start a small
> drill.
> I file or grind a flat if there is a bit sticking out above the head to
> start it centered. If its below grade, just try to punch a flat spot and
> center punch it so a small bit can be started in center. I have a larger
> punch that I made to fit into an 8mm hole and ground the tip into a center
> punch, so the hole trys to help keep the center punch straight. Drill bits
> wander a bit, so you need to be very careful to keep on top of it..Try
> tilting the drill to re center if need be..By all means, do not push the
> drill bit very hard in the beginning or it will break off...Just a
> starting
> hole will do so you can continue with a larger bit...Many times you will
> end
> up crooked or off center no matter how careful you were.
> In that case, just get rid of the existing stud and try to get it
> straightend out after with the larger bit and do the timesert or helicoil.
> Patience is key...Beer is not a necessity, but may help in
> moderation...Oh...and good luck...you will need it.
> Daryl of AA Transaxle
> (425) 788-4070
> aatransaxle.com
> ----- Original Message -----
> From: "craig cowan" <phishman068@GMAIL.COM>
> To: <vanagon@GERRY.VANAGON.COM>
> Sent: Tuesday, March 18, 2008 9:19 AM
> Subject: Re: Exhaust stud replacement on heads
>
>
> > how do the professional shops do this?
> > especially lining up the drill/press to drill a proper hole
> >
> > I know of at least one "professional" shop here in PA that i'd recogmend
> > whole heartily against! They did this repair in the van.....and broke
> off
> > a
> > drill bit in my head....
> > Lets just say they never "Fully repaired" it. Now it's getting the
> > attention
> > it needs : )
> >
> > -Craig
> > '85GL
> >
> > On Tue, Mar 18, 2008 at 11:15 AM, thomas LaPointe <vanagonmail@gmail.com
> >
> > wrote:
> >
> >> Good Morning all...
> >>
> >> I have been searching the archives, but have  not found any repair
> advice
> >> on
> >> replacing the exhaust studs on the waterleaker heads. we need to
> rebuild
> >> a
> >> set I have and have done one with helicoil, but wondered if there is a
> >> more
> >> proper/better way to do this. how do the professional shops do this?
> >> especially lining up the drill/press to drill a proper hole. also, how
> >> deep
> >> can you go before striking water!
> >> thanks, Thomas
> >>
> >>
> >> --
> >> 1985 Full Westy "Rustfalia"
> >> 1982 Full Westy "dead engine"
> >> 1991 GL
> >> 1972 Honda Z600 2 cyl
> >>
>