Date:         Tue, 26 Aug 2008 07:37:45 -0700
Reply-To:     dylan friedman <insyncro@YAHOO.COM>
Sender:       Vanagon Mailing List <vanagon@gerry.vanagon.com>
From:         dylan friedman <insyncro@YAHOO.COM>
Subject:      Re: Header bolts broken
Comments: To: Dennis Haynes <d23haynes57@HOTMAIL.COM>
Content-Type: text/plain; charset=us-ascii

As always, Dennis is right on point.

I would like to add to watch your depth the first time drill a stud out.
Yes, I have put the drill bit right in to the head and had coolant coming flying in my face, fun.

When the job goes south and the hole is off center, I have drilled the entire stud out and gone to the next size helicoil. Making a heli in a heli will reduce down to the right size.
I stud must be used in this case, not bolts.
RED loctite is a must and I always let it set for at least 12 hours before turning over the motor.
Slightly enlarging the mounting holes on the header flange will help match up as well.

Sloppy flanges can be helped by using two brand new gaskets with the metal side facing the exhaust port and the flange. Hi Temp RTV lightly used spread and allowed to skin over before being applied will seal very well.

dylan



----- Original Message ----
From: Dennis Haynes <d23haynes57@HOTMAIL.COM>
To: vanagon@GERRY.VANAGON.COM
Sent: Tuesday, August 26, 2008 8:33:20 AM
Subject: Re: Header bolts broken

Metric hardware is not rated by grade, but by property class. The common
classes are 5.8, 8.8, 10.9, 12.9, and some real special stuff is 14.9. Yes
the exhaust studs are most liklely 5.8 or 8.8. Almost all repalcment studs
are 5.8 unless you go for a better spec.

Twist offs are the hardest to remove since it will be difficult to get a
drill bit started. Get an air grinder or Dremel and grind the end smoth and
use a good sharp punch to get a center dimple. Start with a 1/16" bit ans
work you way up. Be very carefull not to break the bit. A small right angle
air drill and removing accesrories will allow you to get in there. If you
are carefull and lucky you may be able to drill out the old botl and use a
standard tap to clean out and repair the hole. If you need to heli coil, the
new exhaust can e set in place and used as a guide. There is no need or
benifit to extra lenght or double inserts. The single coil will be more than
adequate to hold the bolt in place especially if using stainless. Note how
the heli coil lenght is almost the same as a nut.

IF goiing for Stainless hardware, look for 316 (A4). It performs slightly
better than the 18-18 (A2).
Stainless to Stainless connections always need a nickel based anit seize or
maybe loc tite as a lubricant to keep the threads from galling.

Dennis



>From: Cullen Stewart <cullberly@VERMONTEL.NET>
>Reply-To: Cullen Stewart <cullberly@VERMONTEL.NET>
>To: vanagon@GERRY.VANAGON.COM
>Subject: Header bolts broken
>Date: Mon, 25 Aug 2008 22:33:23 -0400
>
>The worst has happened. After very patiently removing the nuts and bolts on
>my wbx I twisted 2 off and still have 1 to go. They are flush with the head
>and have nothing to grab onto. What are my options with out removing the
>head. They are obviously not grade 5 or 8, but good old garbage grade 2
>considering they twisted off with a minimum amount off force. Is it
>possible to helicoil these while in the van?