I use the Snap On brand 1/8 inch double ended drill bits to start the
drilling you can guide the bit with some angling
to keep it on track.
these bits are short and sharp

B Bob

----- Original Message -----
From: "aatransaxle" <daryl@AATRANSAXLE.COM>
To: <vanagon@GERRY.VANAGON.COM>
Sent: Tuesday, March 18, 2008 9:55 PM
Subject: Re: Exhaust stud replacement on heads

> 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
>>>
>