Date: Sat, 13 Aug 2005 20:35:28 -0500
Reply-To: Larry Alofs <lalofs@RCN.COM>
Sender: Vanagon Mailing List <vanagon@gerry.vanagon.com>
From: Larry Alofs <lalofs@RCN.COM>
Subject: Re: Advice if you ACTUALLY REPLACED your exhause headers
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Ed wrote:
> I received several general warnings about having the right tools, and what a pain it can be, but is there anyone out there
who can answer my original question- What specific difficulties did
you encounter if you replaced your header pipes?
Any advice on overcoming these difficulties?
>
> Thanks
> Ed
>
Rust and corrosion.
Nuts and bolt heads which were 13 mm typically have eroded so that a 13
mm 6 pt socket slips. (Always use 6 pt sockets)
If the nut is about the right shape You may be able to drive a 7/16"
or 12 mm socket on and get enough grip. I believe that I once even went
down to 11 mm.
Of course these fasteners should be soaked with PB blaster or Rust
Eater, etc. for as long as practical before even trying to turn them.
It may help to apply your liquid of choice when the engine is warm. It
may also help to tap the offending part 200 times. :-)
When removing steel bolts or studs from an aluminum head, personally,
I want the aluminum cold as when removing spark plugs. Maybe this is
just a superstition; metallurgists on the list may correct me.
Heating frozen nuts is of course a common strategy, but a flame has
to be handled very carefully in such close quarters. An oxy-acetylene
torch with a small tip is best, because it can heat the part quickly.
Second best is probably a MAPP gas torch, but the flame is spread out
more. Ordinary propane might do the trick if that's all you have.
Other things to try when desperate:
Cut most of a nut away with a Dremel, carefully so that you don't
hurt the stud.
Stretch a nut by squeezing it as hard as you can in three different
directions with large ViseGrips.
If you remove a bolt or stud from the aluminum head and the new bolt
doesn't go in well because of dirt or corrosion and you don't have a
metric tap to clean it out, you can make a crude thread chaser from an
extra bolt. Cut a couple of longitudinal slots across the threads with
a Dremel cutoff wheel. Then clean off the burrs with a small file.
Use stainless steel when reassembling. Anti-seize compound where steel
meets aluminum is also a "good thing".
Good luck,
Larry A.
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