The cold isn't what kills fuel lines. The fuel is.

Winter temps alone won’t ruin rubber fuel lines and primer bulbs, but the stale ethanol gas sitting inside them will — so yes, inspect both before you start anything in spring.

Cold makes rubber stiff, not dead. If your lines go into winter in decent shape, a few months of freezing temperatures won’t crack them. What kills them is ethanol fuel sitting in the system all winter. Ethanol pulls in moisture, varnishes up, and slowly eats the rubber from the inside. By spring, a line that looked fine in November can be gummy, swollen, or brittle.

Primer bulbs are the usual weak point. They take UV, heat cycles, and fuel exposure all year, and they crack from that long before winter does anything to them. A cracked bulb won’t build pressure, so fuel never reaches the carb — the number one “it won’t start” excuse in spring.

So before the first start, give the lines a squeeze and a flex. Look for cracks, bulges, or wet spots. Press the primer bulb a few times — it should feel firm and spring back. If anything looks tired, or you can’t remember when you last replaced it, just do it. Lines and bulbs are ten or fifteen bucks and ten minutes of work. Not worth troubleshooting season over.

An hour of cheap insurance in March beats a whole Saturday of “why won’t this thing start” in April.