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.
Best answer: The best time to plant grass seed is in the fall, only if you can answer yes to all those questions. Realistic answer: When to plant grass seed in any location? When you are ready. Any time, any season, that you can answer yes to all of these questions will probably work.