Re: [alfa] Liner seals

[Michael Findlay <michael@xxxxxxxxxxxxxxxxxx>]

Hi Alfisti

Thanks for the informative responses to my question about sealants. I 
summoned up my nerve on the weekend and assembled the liners using 
Loctite 510 gasket eliminator. This is apparently safe up to 400 
degrees F and produces a very tight seal. I made certain that the 
liners were protruding equally at .02mm and used a temporary 
restraining tool to hold them in place while the gasket set. The 
disadvantage with this type of form in place anaerobic material is that 
the liners are now well and truly stuck in place. I looked at the O 
rings supplied in the gasket kit and I doubt that they could be any 
real aid in providing any 'lift' for the liners as has been suggested 
in some postings. Also, I may be wrong but I thought the thermal 
expansion characteristics of aluminium and cast iron were similar so 
there should not be any real movement in the assembly once clamped 
down.  Only time will tell if this has been a success but I will 
provide a full and frank confession if the whole thing fails.

Michael Findlay
1750 GTY
Fiat Marea Weekend 2.0

On 13/11/2004, at 3:45 AM, Jim Steck wrote:


> Michael,
>
> There are a couple advantages to using silicone sealer . . . any good 
> one will
> do . . . instead of the o-ring seals when rebuilding an Alfa.  If 
> there is any
> corrosion on the liner or block sealing surface, an o-ring may not seal
> proplerly . . . only a problem on a rebuild.  Second, the liners are 
> held in
> position by the cured sealer and hold-downs are not needed during 
> assembly.
> Third, it's easy to get accurate measurements of liner projection.  
> Fourth, it
> helps holds the liner in place at high RPM.
>
> I'm very careful cleaning the oil film from the parts.  The final 
> cleaner is a
> detergent like 409 or Fantastic . . . solvents don't remove all the 
> oils.  Put a
> bead of silicone around the liner about 10 mm down from the sealing 
> surface . .
> . something like a 3-4 mm bead.  The idea is to get some sealer in the 
> clearance
> between the block and O.D. of the liner.  Then install the liners, and
> temporarily install the head with a used gasket.  You only need 35-40 
> lb-ft of
> torque on the studs.  Let sealer cure for at least 8 hours.  I put a 
> trouble
> light against the block to accelerate the cure.  Remove the head 
> inspect the
> bead of silicone that has squeezed out around the base of the liners.  
> Measure
> the liner projection and then assemble normally.
>
> The liners can still be removed if necessary . . . but you will need a 
> puller
>
> Regards,
> Jim Steck
> ---------------
> AutoComponenti
> 8906 Darke County Line
> Brookville, OH 45309
> ph: (937) 884-5142
> fax: (937) 884-5144
> email: jim@domain.elided
> web: www.autocomponenti.com
>
>
>
> From: Michael Findlay <michael@domain.elided>
> Subject: [alfa] Liner seals
>
> Hi Alfisti
>
> I have heard that some 105 engine builders are using sealant to ensure
> there is no coolant leakage from the bottom of the liner. Is this good
> practice? Should the sealing rings be used as well as sealant or should
> these be left out? Should the sealant cover the surface below chamfer
> for the O ring or simply the area where the O ring should be? Does
> anyone have a recommended sealant?
>
> Thanks
>
> Michael Findlay
> 1750 GTV
> Fiat Marea 2.0 Weekend
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