[Farmall] Progress on my Int. 184 engine overhaul

[szabelsk at gdls.com]

With regard to honing the cylinder walls, I was always told that the main 
objective when honing the cylinder walls is to make the walls as straight 
as possible (no taper), the bores as round as possible (minimal 
distortion, which is especially important with low tension rings), to have 
the right amount of crosshatch for good oil retention and ring support, 
and to produce a surface finish that meets the requirements of the rings.

Just recently I've seen several instances where honing is not required or 
recommended when rebuilding engines. Are newer blocks that much better 
than older blocks that they don't need to be honed any more? Maybe with 
newer engines the tighter tolerencing on all the piston related parts 
doesn't produce as much wear on the cylinder walls as on older blocks????? 
Don't think so.

Honing is a science in itself. The type of ring that is going to be used 
determines what grit of stone should be used for the honing process. Also, 
how the stones are made affect the outcome of the polished walls. Two 
stones of the same grit can produce different finishes due to the amount 
of bonding agents and fillers used to make the stones. The type of oil 
used during the honing process also affects the outcome, as does the 
honing pressure, head speed, stroke rate and hardness of the block itself. 
The ring manufacturer has their own preferred surface requirements to 
prevent excessive ring wear, and they should be consulted to see what grit 
and type of stone should be used for honing.

Then there's the fact that the stones themselves wear and should only be 
used so many times before they need to be replaced. Usually the stones 
should be replaced after every 24 cylinders worth of honing.

It's surprising that most engine rebuild shops have been found not to have 
any way of checking that the walls have been done right. They just hone 
"the old fashion way" and don't have the equipment (a profilometer) 
necessary to check the finish parameters such as core roughness, average 
peak height, average valley depth, bearing areas, etc.. 

Carl Szabelski




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