> Twice this year I have rebuild the engine in my Midget for less than
> $700 each time, this includes parts and machine shop costs.
>
> - Cylinder head rebuild (includes news valves and guides) - $170
> - Crank reground and new bearings - $50
> - New pistons and rings - $340
> - Block rebored/honed etc - $76
> - Oil pump - $34
> - Other misc machine work - $70
>
> There are certain important factors that you need to know when doing
> any machine work -
> eg - each cylinder has to be re-bored for a specific piston. If you
> get oversize pistons of say +.010 and re-bore the cylinder using +.010,
> that does not mean that the piston will fit !!!!!. You have no guarantee
> that the piston is perfectly round !. Therefore the cylinder has to be
> re-bored to match a specific piston.
>
If you don't have a significant ridge at the top of the cylinders I would
_not_ replace pistons. I've always sent the cylinder head out to a good
machine shop, and had them check it over, regrind the valves, mill the
surface, and replace any and all bad parts. I do not replace things for
the sake of replacing them. Exhaust valve seats on a leaded gas-only
engine would be an exception. On the bottom end, replace all timing
components, main, rod and cam bearings. Replace the piston rings, have
a machine shop check your connecting rods for straightness. (Make sure
to label the front of each piston, and the cylinder number for each).
Replace the oil pump, hone the cylinders to break glaze on them. The
amount of work needed to do what I've outlined is about half the work
needed if you are going to rebore the block, and results in just as good
a job as long as you have no ridge.
If you have a ridge, it probably is a good idea to rebore the block and
replace the pistons with oversize. If you do this, make sure to have the
machine shop pickle the block. This will cost you a few extra bucks, and
force you to replace the freeze plugs, but results in absolutely clean
oil galleyways.
Joe
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