Oil pump piston, some questions.

[The Radium King]

yeah, adding washers (ie compressing the spring) doesn't change the rating of the spring. springs are rated at # / ". ie, it will take 40 lbs of force to compress a 40 #/" spring one inch. it will take another 40 lbs to compress it the next inch. ie, a total 80 lbs to compress two inches.

so, while the washers compressed your spring (and reduced amount of available travel) you didn't change the force required to compress the spring.