Checking the spark gap on spark plugs, and other small clearances
With a straight edge and feeler gauges.
Feeler gauges.
a feeler guage cannot be calibrated, it is made at precise measurements that cannot be changed. When a feeler guage is out of spec, it is replaced.
Nonmetallic feeler gauges are used by technicians to measure the air gap that exists between the coil body and the armature on an electro-magnetic brake. This type of braking system generally can be found on industrial cranes and on marine davit hoist systems.
feeler ka
They work well for checking gaps and clearances such as the amount of backlash between the cam and lifters.
An electronic way of setting the gap in ignition points. This is more accurate than using feeler gauges.
Stock 350's have hydraulic lifters, so feeler gauges aren't needed. Get yourself a Chilton's manual or similar and read up on the valve adjustment process.
Valve clearances are measured with feeler gauges on cold aircooled engines or warm water cooled engines.
If you're asking about feeler gauges, then a pair of 0.002 plus an 0.001 would do, but make sure they are very clean and undamaged.
Most common is fuel gauges in power equipment. The gauge is in the fuel cap
You will need feeler gauges, a ring spacer and separation tool, the correct specs for their correct placement on the piston and the gap specs.