In the Railroad and heavy equipment industries, Kroil seems to be a popular penetrating oil.    I have never done a comparison between Kroil and PB Blaster so I cannot give a more objective opinion.    Some people like to hammer on the nuts and bolts lightly in order to loosen the thread fixing.    Some people think its better to apply heat.    Essentially I think it is necessary to use care and prudence and/or attention to detail as some folks put it :-)    Avoid brute force LOL especially on smaller fastenings like M5, M6 etc as they are so easy to snap off.

Steve

On Feb 5, 2014, at 8:23 PM, Stuart MacMillan <stuartmacm@gmail.com> wrote:

> It's four nuts and studs and four bolts to the heads. On some (most?) you'll
> only be able to get a vise grip on because the pipe curves over what's left
> of them. And then you snap off the corroded stud/bolt and you'll have to
> drill and extract it.  It can be a nightmare, which is why it's easier to
> pull the engine when doing the heads if the nuts are severely corroded.
> Plan on replacing all the nuts and bolts, and all of the gaskets.
> http://www.van-cafe.com/home/van/page_567_279/exhaust-hardware-kit.html 
> 
> Try soaking overnight with PB Blaster and hope for the best.
> 
> Good luck!
> 
> Stuart
> 
> -----Original Message-----
> From: Vanagon Mailing List [mailto:vanagon@gerry.vanagon.com] On Behalf Of
> Steve Cotsford
> Sent: Wednesday, February 05, 2014 5:03 PM
> To: vanagon@GERRY.VANAGON.COM
> Subject: Re: Cleaning/Checking Cylinder Head Question Follow Up
> 
> So what is the best and safest way to remove the cylinder head exhaust studs
> and bolts or nuts ?    Probably they have very many years of rusting so
> soaking them in PB Blaster or Kroil is certainly going to be necessary.  I
> would guess driving on a socket of perhaps 1 size smaller than the nominal
> size so that there is less chance of slippage and rounding off of the nuts.
> Should one dispense with that and use a dremel thin grinding wheel to
> carefully grind off one area of the nuts so that they can be broken off the
> studs without stud damage?    Cleaning off the threads remaining with the
> correct size thread die so that new nuts will fit nicely?        Once again
> I would like to hear the opinion of those who have successfully done this
> troublesome job.         Thanks,   Steve
> 
>