<VV> Main Bearings - how perfect does the surface need to be?

[Bruce Schug]

On Jun 21, 2008, at 5:24 PM, BobHelt at aol.com wrote:

>
> In a message dated 6/21/2008 7:42:01 AM US Mountain Standard Time,
> bwschug at charter.net writes:
>
> Interesting scenario. But Bob, if there's a scratch, that means
> there's an actual groove or gouge in the metal. You say that's okay,
> but that there shouldn't be any metal sticking up. But, if there's a
> groove, where did the metal go that was in the groove? Was it   
> removed?
> Was it compressed? Was it raised? It seems to me these are  the only
> possibilities and that the last one, that the metal was  raised is the
> most likely scenario. So, if there's a scratch and the  metal was
> raised, then the clearance is no  longer constant,  right?
>
> Bruce
>
>
>
> Hi Bruce,
> Please go back and re-read my posting. I think that you missed what  
> I was
> saying.
> Regards,
> Bob Helt
>
> In my opinion, the surfaces that contact the crank should not have   
> any
> raised portions due to gouges. Small indentations won't hurt. If
> there are any raised portions either file them down or gently tap  
> them back
> in
> with a small hammer (ball peen is best). Just remember that you   
> want a
> constant
> clearance of about 0.002 in. between the journal and  the bearing.
> Scratches probably are all Okay because they likely contain no  raised
> material.
>

Bob,

I hate to beat this to death, but you said, "Scratches probably are  
all Okay because they likely contain no  raised
> material."

Now, isn't a scratch simply a shallow gouge? This scratch is what I  
was referring to. That's why I hypothesized that the material that was  
where the scratch  now is, has either been compressed, removed, or  
displaced above the surface (like a gouge?).

Are you sure that a scratch doesn't have any raised material? After  
all, isn't one man's scratch simply another man's gouge?

Bruce




Bruce W. Schug
Treasurer, CORSA South Carolina
Greenville, SC
Stock Corvair Group Member
bwschug at charter.net

CORSA member since 1980

'67 Monza. "67AC140"