Re: Rebuilding cylinder heads

[EldonMcf@domain.elided]

In a message dated 4/11/99 11:27:10 PM Central Daylight Time, Roger Scow 
<rscow@domain.elided> writes:

>  Harvesters:
>  
>  When I went to start rebuilding the heads (ie valve spring assys), I 
noticed
>  that I had eight little bronzey-colored disks.  They are smooth on one 
side,
>  and say "this side up" and have radial lines enscribed on them on the flip
>  side.  Otherwise, they look like washers.
>  
>  They don't show up on the diagram in the book.  I get the feeling they are
>  supposed to go under the rotocaps under the exhaust valve springs.  I
>  suppose they are supposed to keep the bottom of the rotocap from turning, 
so
>  that the top can.
>  
>  I only have eight...and I got the heads back disassembled from the machine
>  shop.
>  
>  Are any of you folks familiar with these things?


    Roger,

          Those are called Valve Spring Inserts, or sometimes called shims.  
They are used to make up for the loss in spring tension, and increased valve 
spring assembled height from removing material from the valve, and seat when 
the valves, and seats are refaced.

    They are not used from the factory, so they must have been installed 
during a previous repair.  These inserts are available in 3 sizes A = .060", 
B = .030", and C = .015". The bronze colered ones are probably the A size.  
The serrated side is placed twords the cylinder head to help keep the heat 
from getting to the springs.

   I would recommend testing the valve springs, and replacing any that are 
weak, or worn.  then measure the assembled height between the cylinder head, 
and valve spring retainer, and select a shim that will get the assembled 
height close to the stock measurement.  There are hardened shims available 
that should be used for IH engines.  The shim used should be the same size 
for all valve springs, occasionally it may be neccessary to use a different 
size for intake, and exhaust.

>  
>  
>  Roger
>  '78 Traveler/392E/727
>  Beaufort, South Carolina


Eldon McFarling
Ceresco, NE
IH DIESEL PAGE
http://members.aol.com/EldonMcf/