<VV> '65 Project coming to a close...

Frank DuVal corvairduval at cox.net
Mon Dec 17 07:35:47 EST 2007

If he can't measure the rod ends or crank, he does not know if grinding 
the crank will help the problem. He may end up with .015 or so clearance 
and be too large for .010 bearings if the rods are too big.

Frank DuVal

Ron wrote:

> The .000 would be a bearing for a standard size journal.  The other 
> dimensions are undersized shells to compensate for a worn journal as 
> the measured .008 plastigage reading would indicate so Jason is 
> correct with his concern.  He should check the other journals and if 
> consistent, the crank needs to be ground down to .010 undersized and 
> .010 shells used.
> RonH
> ----- Original Message ----- From: "Frank DuVal" <corvairduval at cox.net>
> To: "Jason Morri" <neosore at gmail.com>
> Cc: <virtualvairs at corvair.org>
> Sent: Sunday, December 16, 2007 10:13 PM
> Subject: Re: <VV> '65 Project coming to a close...
>> Three points:
>> 1. You don't want to get to .000. If you did, the bearing would seize 
>> up as there would be no space for oil.
>> 2. Did you move the rod relative to the crankshaft while the 
>> plastigage was in place? This can cause a smeared reading which is 
>> usually interpreted as smaller clearance, but I had to ask....
>> 3. The shop said the crank was OK for std bearings. Did anyone check 
>> the hole in the rods? It is very common for the holes to be elongated 
>> in the rods. A typical rod needs to go to the machine shop and have 
>> the cap ground down slightly and the hole honed back to standard size.
>> Plastigage used correctly is a good indicator of clearance on parts. 
>> But, it only measures clearance, not the size of any part.
>> Frank DuVal
>> Jason Morri wrote:
>>> After almost two years I'm happy to report that my '65 Monza has 
>>> completed
>>> the body and paint portion of the restoration (boy was there a lot of
>>> rust!).  (Picture here: 
>>> http://alamocitycorvair.org/PIC/65%20corvair.JPG )
>>> The only major project left is to rebuild and install the engine.  
>>> Which is
>>> why I'm writing this email.
>>> After cleaning and prepping all the engine parts (including having 
>>> the heads
>>> professionally rebuilt, cylinders honed, new pistons pressed onto 
>>> the rods,
>>> etc.), I started the reassembly process by first checking the 
>>> clearance on
>>> the rod bearings.  Even though the machine shop told me my crank was 
>>> in spec
>>> for STD bearings, I still used some plastigage to make sure.  I 
>>> checked to
>>> make sure the rod bolts were tight and torqued them to 30 lbs.  Well 
>>> long
>>> story short after checking different rods multiple times, I'm 
>>> showing a .008
>>> clearance.  Which means, according to the assembly manual, I'm .005 
>>> over the
>>> max.
>>> My question is, is this something that I should worry about?  Should 
>>> I trust
>>> the machine shop or trust the plastigage (which by the way, is the 
>>> first
>>> time I've ever used it).  I checked Clarks and they only have rod 
>>> bearings
>>> that are .000, .001, .002, .010.  How does one get to .000 with a .008?
>>> Thanks for any help that can be provided.
>>> Jason Morris
>>> Jmorris at AlamoCityCorvair.org

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