In general, James is right, they're easy to rebuild. However the accelerator pump assembly is characteristically sort of finicky on this model. Just be careful not to damage the diaphragm or metering rod while you're rebuilding it.
forget that..... for 105 dollars on advancedautoparts.com i can't be bothered to rebuild mine and then tinker with it to get it to run...just lazy i guess. my accelerator pump is gone.