KLMHT Gas Tank and Cap Replacement for Briggs & Stratton E450/E500 — Direct-Fit 590568/799585 Assembly, Venting & Seal

KLMHT replacement gas tank (590568 / 84004660) with matching cap (799585) restores secure fuel storage and proper ventilation for compatible B&S E450/E500 lawnmower engines.

If your mower’s original fuel tank is cracked, brittle, or the cap no longer seals, fuel can leak, fumes can build up, and engine performance can suffer. This KLMHT assembly replaces parts 590568 (tank) and 799585 (cap), cross-referenced as 84004660, fitting a range of Briggs & Stratton-style E450 and E500 series powerheads and engines listed under part groups such as 08P502, 08P602, 09P602, and 09P702. The unit arrives as a direct-fit aftermarket component designed to match mounting points, fill openings, and venting locations so installation is straightforward for a technician or a confident DIYer.

Will this tank and cap fit my mower model?

The KLMHT set is manufactured to replace OEM numbers 590568 (tank) and 799585 (cap) and is also referenced by KLMHT part 84004660. It is engineered for E450 and E500 series engines and many lawnmower applications listed under 08P502, 08P602, 09P602, and 09P702. Compare your mower’s existing tank shape, mounting ears, and fuel outlet location to confirm compatibility before purchase.

• Replaces OEM: 590568 tank and 799585 fuel cap
• KLMHT part reference: 84004660
• Common fits: E450, E500 series engines
• Fits engine groups: 08P502, 08P602, 09P602, 09P702

How does swapping the tank and cap impact mower safety and performance?

A fresh tank and a proper sealing cap reduce the chance of fuel leakage and vapor escape, lowering fire risk and preventing fuel starvation issues that can cause the engine to stall. Better venting and clean fuel containment help the carburetor receive consistent fuel, which supports smoother starts and steadier throttle response. The replacement also eliminates deterioration points such as cracks, brittle plastic, and warped sealing surfaces.

• Prevents fuel leaks and vapor loss
• Reduces engine stalls from fuel delivery problems
• Maintains correct fuel ventilation and pressure balance
• Replaces deteriorated plastic and worn seals

What should I expect during installation and maintenance?

Installation is typically a bolt-on swap: drain any remaining fuel, detach the old tank and cap, and transfer mounting hardware or grommets as needed. Verify hose connections, vent tubing routing, and tighten the cap to spec; replace any fuel lines that look hardened or cracked. After installation, inspect for leaks with a small amount of fuel in the tank and recheck fasteners after the first 1–2 hours of run time.

• Drain old fuel before removal
• Reuse mounting hardware or replace if corroded
• Check fuel lines and vent routing
• Run brief leak test and re-torque fasteners after initial use

What materials and quality details does this replacement offer?

The tank is molded from durable, fuel-resistant polymer engineered to withstand outdoor temperature cycles and gasoline exposure. The cap features a sealing gasket and a venting mechanism compatible with typical small-engine requirements. Though an aftermarket part, it aims to match OEM dimensions and key interface points for a reliable fit and function.

• Fuel-resistant molded plastic tank construction
• Cap with gasket and built-in venting
• Designed to match OEM mounting and outlet locations
• Intended for outdoor power equipment durability

Who is this for: Owners, repair shops, and maintenance technicians who operate or service lawnmowers and outdoor power equipment with Briggs & Stratton-style E450/E500 engines needing a direct replacement gas tank and cap. Choose this KLMHT assembly when the original tank shows cracks, the cap won’t seal, or you want a like-for-like fit to restore safe fuel containment and dependable engine operation.