F-ber 4 Pieces 694395 Primer Bulb for Briggs and Stratton Lawn Mower Replacement for 5085 5085H 5085K 496115 4180 122K02 122K82 124K02 12A800 12F702 12F707 12F782 12G802 127800

What It Is

This is a set of four aftermarket primer bulbs designed to replace worn or cracked bulbs on Briggs & Stratton lawn mower engines. The primer bulb draws fuel into the carburetor to aid cold starts, commonly used on walk-behind mowers, tractors, and small engines.

Fitment & Compatibility

Before buying, verify your engine model number (e.g., 12A800, 12F702, 127800) stamped on the engine shroud or valve cover—not the mower deck. These bulbs fit specific Briggs & Stratton engines listed in the title, including series 5085, 5085H, 5085K, and others like 122K02, 124K02, 12G802. The OEM part number is 694395; cross-check against your carburetor’s primer bulb hole diameter (typically 0.5 inches). They are aftermarket replacements, not OEM, but match the original dimensions for a snug fit. Avoid assuming compatibility with other brands or non-listed engine models.

Key Things to Know

• Quality: Users report the rubber is slightly stiffer than OEM but seals well and lasts through a season or two. Check for cracks during installation.
• Installation: Easy—pull off the old bulb, push the new one into the carburetor recess. No tools needed, but ensure the bulb seats fully to avoid air leaks.
• Common Gotcha: If the mower still won’t prime, the carburetor gasket or fuel line may be the issue, not the bulb. Also, these bulbs are sold in a 4-pack, so you’ll have spares for future replacements.
• Price vs. Value: At $5.99 for four, it’s cheaper than buying single OEM bulbs (often $3–$5 each). Good for multiple mowers or long-term storage.

Should You Buy It

Buy this if you need a quick, low-cost fix for a hard-starting Briggs & Stratton engine with a cracked or missing primer bulb, and you’ve confirmed your engine model is on the compatibility list. It’s ideal for DIY homeowners who want spares, but skip it if you prefer OEM parts for exact rubber texture or if your carburetor has other issues.