Re: Prior to head gasket replacement

[drubie@xxxxxxxxxxxxxxxx (David Rubie)]

From: Paul Weimer <tn010151@domain.elided>
> RE: 1969 1750 Spider
> 
> Now I looking in the engine bay for proper things to clean, adjust,
> check-out, etc.  First question that comes to mind is what is the
> recommended procedure to properly remove the remains of the old head
> gasket from the block?  I got out my trustly gasket scraper, but when I
> looked that aluminum block I put the scraper back in the drawer.  I seem
> to remember reading somewhere to use oven cleaner to soften and remove
> gasket material from an aluminum surface.  Am I remembering this
> correctly?  Are there commercial products designed specifically for this
> job that is recommended?

I use a product called "CRC Gasket Remover" which is supposed to
be safe for aluminium.  It's good for removing thin bits of gasket, but
won't do much for big, stuck on chunks.  Go get that gasket scraper,
you'll need it.  You should be careful though, try not to remove any
metal from the gasket surface.  A few scratches are OK, but removing
big chunks will see you with a water leak I think.

> 
> Noticed that three of the head-to-block studs have a white, kinda
> powderly, coating on them.  Planned to clean them up, but is this the
> trail of something I should be aware of?
Normal, AFAIK.  Make sure you use a corrosion inhibitor in your
coolant.  There have been plenty of debates on the merits of
different kinds of water to use (de-mineralised, de-ionized, distilled, 
you name it) but I just use tap water.  (Sydney tap water, that is,
so I hope the Alfa doesn't get Giardia :-).  I'm guessing, but the
white/brownish powdery buildup is actually mineral salts from your
water.

When I had my engine apart last time, I grabbed a fine brush wire
wheel and put it in my drill, cleaning up the threads of the
head studs rather than worrying about the shafts.  Give them a good
cleaning out so the threads are nice and clean and then oil them with
some engine oil.  It makes putting the head bolts on easier and you will
get a more accurate torque reading from your torque wrench when everything
goes back together.  You might want to cover over the pistons while
you're doing this, it can get messy.


> 
> When I install the new head gasket (purchased from IAP) any need for use
> of any sealant on either surface?
The last gasket I used didn't require sealant.  There is usually some sort
of heat based glue on one side of the gasket already there.  You might
use goop on the other side, but I've always used nothing.  That's not
to say I haven't had head gasket problems, but they're usually from
forgetting to re-torque the head after a couple of thousand kilometres.

> 
> Use anti-seize on the head bolts?
Engine oil will do.

dave.

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