594601 594605 Carburetor For Nikki 33R877 331877 795366 698945 594492 697216 31P677 799256 699475 Craftsman YT3000 YTS3000 LT3000 DLS3500 MTD Bolens 13AM762F765 Mower

What It Is

This is an aftermarket carburetor assembly (models 594601 / 594605) designed to replace the Nikki carb found on many Craftsman, MTD, and Bolens lawn tractors. It meters fuel and air into the engine—critical for starting, idling, and cutting performance.

Fitment & Compatibility

Before buying, confirm your engine model (not just the tractor model). This carb fits Nikki 33R877, 331877, 795366, 698945, 594492, 697216, 31P677, 799256, and 699475. It works on Craftsman YT3000, YTS3000, LT3000, DLS3500, and MTD/Bolens 13AM762F765 mowers—but only if they use a Nikki carb with the same bolt pattern and fuel inlet orientation. Measure the mounting flange bolt spacing (typically 2.5" center-to-center) and check that the fuel line barb is the same diameter as your existing hose. This is an aftermarket part, not OEM, so gasket thickness or jet sizing may differ slightly.

Key Things to Know

• Quality is hit-or-miss: Many users report it works well out of the box, but some get units with debris in the bowl or misaligned float. Inspect and clean before install.
• Installation is straightforward: Requires removing the air filter housing, disconnecting fuel line, and swapping two bolts. No special tools needed, but a carburetor adjustment tool helps set idle mixture.
• Common gotcha: The included gaskets may be thinner than OEM. If you get a vacuum leak, stack the old gasket with the new one or use a thin layer of gasket sealant.
• May need tuning: After install, adjust idle speed and mixture screws (typically 1.5 turns out as a baseline). If the engine surges or dies under load, the main jet may be slightly lean—consider reusing your old jet.

Should You Buy It

If your original Nikki carb is clogged, warped, or beyond cleaning, this is a budget-friendly fix that works for most DIYers. It’s not for professional landscapers needing OEM reliability, but for a weekend mower that won’t start or runs rough, it’s a solid gamble at $22. Just be prepared to clean and tune it.