When using the single-vacuum distributor, the vacuum hose runs from the vacuum port on the left side of the carburetor to the vacuum canister on the distributor. In that case, the vacuum port on the rear of the carburetor must be plugged.
For most cool season grasses and for folks living in northern climates, the best time to plant grass is in late August, early September. Depending on exactly the climate you have and the type of grass seed you're planting.
Sow seed outdoors when the soil can be worked in spring. Place transplants in the garden when they are 3 to 4 inches tall as early as 3 to 4 weeks before the last frost in spring. In mild-winter regions, start seed in late summer for a winter or spring harvest.