How to Fix Old-School Ignition Points: DIY Auto Got a collector car with
ignition points? Here's how to replace the points and set the timing. By Mike
Allen December 18,2009 3:30 AM "It's not a heap,dad. It's a classic."That's
harder to justify when your classic muscle car won't start. Nothing like a
high-compression V8 combined with a battery that hasn't seen a charge for a
month and a half to make for slow cranking. Add in the indifferent,low-energy
spark and incorrect ignition timing caused by worn-out points autel
maxisys pro ms908p,and you've got an engine that won't fire--oh,and wet
spark plugs too. Modern engines use computer-controlled factory-preset
self-adjusting ignition systems that never change their timing,have no moving
parts and never need maintenance. Yay! A generation ago,every teenager,every
mechanic and a lot of vehicle owners understood the theory and practice of
changing points and setting the timing. Nonetheless,there are still plenty of
older vehicles,outdoor power equipment,boats and tractors that need periodic
adjustment or replacement. The distributor on these older vehicles performs two
related tasks.
Condensers are inexpensive enough that it makes no sense not to replace them
with every set of points. They should last as long as a set of points,20,000
miles at least. Kettering Ignition: Charles F."Boss"Kettering was one of the
founders of Delco,and the inventor of the battery-point-style ignition
system,first used by Cadillac in 1910. Wear,inaccuracy and high maintenance have
forced car manufacturers to abandon this system,replacing it with computers and
individual ignition coils for every cylinder--and no points to wear out. On
Point The function of the ignition system is to fire the spark plugs at the
correct time,just before the piston hits top dead center (TDC) on the
compression stroke,to ignite the fuel/air mixture,thence producing high pressure
in the cylinder to force the piston down and,subsequently,the wheels to move the
car forward. The spark plug normally fires anywhere from 10 to 45 degrees before
the piston reaches TDC,to allow the fuel/air mixture's flame front to traverse
the combustion chamber Autolink
AL539 Scanner. It takes a few milliseconds for the pressure in the cylinder
to build,and waiting until TDC would make the pressure peak too late in the
piston's downward stroke to be most efficient. Under some engine-operating
conditions,the advance might adjust the ignition timing to as much as 45 degrees
before TDC. Signs of incorrect ignition timing include hard starting,spark
knock,poor power,overheating and decreased fuel economy. This Chevy V8 uses an
old-school Kettering-style ignition distributor. To set the timing after
replacing the points and condenser,you'll need,no surprise,an old-fashioned
stroboscopic timing light.
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