Chainsaw

Echo CS-500P

2-Stroke

The Echo CS-500P is a 50.2cc 2-stroke professional chainsaw designed for regular production cutting — firewood, land clearing, and medium-to-large tree felling with 18" to 20" guide bars. The P suffix indicates professional-grade build quality. It runs a Zama carburetor and features Echo's Vibration Reduction System and G-Force Engine Air Pre-Cleaner. Under professional production use, monthly fuel system service (filter, primer bulb, lines) and air filter maintenance are routine. A reliable choice for arborists who need professional power without moving to the larger CS-590 displacement class.

See a wrong fitment? Report a correction.

Verify before ordering: Fitment can vary by serial number, production date, region, and sub-model. Match the OEM number and physical dimensions before ordering.

Equipment: Chainsaw · 2-Stroke
Covered Parts: Spark Plug, Air Filter, Fuel Filter, Carburetor, Recoil Starter, Primer Bulb, Fuel Line Kit, Chain, Guide Bar, Ignition Coil
OEM References: 90023Y, A226000473, A369000100, A021003390, A180001600, 12318139130, V471001471, P021036741
Model Family: CS-500P
Last Reviewed: 2026-05-20
Data Confidence: Aftermarket-confirmed
Sources Consulted: OEM part references, Aftermarket catalog cross-references, Retailer fitment listings

Quick Fitment

Part Type	OEM / Spec	Common Option	Confidence
Spark Plug	90023Y	Champion CJ8Y	Medium · 2026-05-20
Air Filter	A226000473	OEM A226000473	Low · 2026-05-20
Fuel Filter	A369000100	Stens 610-009	Medium · 2026-05-20
Carburetor	A021003390	Walbro WT-1009	Medium · 2026-05-20
Primer Bulb	12318139130	Zama BG-00-4	Medium · 2026-05-20
Recoil Starter	A180001600	OEM A180001600	Low · 2026-05-20
Fuel Line Kit	V471001471	Stens 115-530	Medium · 2026-05-20
Chain	20", 3/8" pitch, .050" gauge, 70 drive links	Oregon 72LPX070G	Low · 2026-05-20

Tune-Up Kit

Common service bundle: spark plug, air filter, fuel filter, carburetor, primer bulb, fuel line kit.

Maintenance Interval

Inspect filters and fuel lines each season, replace spark plugs during annual service, and service carb/fuel-system parts when starting or idle symptoms appear.

Before You Buy

Confirm the full model is Echo CS-500P, not just the family name.
Check serial number, production date, and regional variant before ordering.
Match the old OEM number stamped on the removed part when available.
Compare dimensions, plug gap, thread, fuel line diameter, or chain pitch/gauge where applicable.

Common Mistakes

Ordering from a family listing without checking the exact sub-model.
Buying a kit that includes the headline part but wrong gaskets, lines, or bulb size.
Choosing the wrong carburetor revision when multiple versions were used.
Assuming all fuel line kits use the same diameter and routing.
Installing the correct plug number with the wrong gap.
Matching bar length but missing pitch, gauge, or drive-link count.

Symptoms Map

Won't start

Spark plug, fuel filter, primer bulb, carburetor

Starts then dies

Fuel filter, fuel line kit, carburetor

Bogs under throttle

Air filter, carburetor, spark plug gap

Primer will not fill

Primer bulb, fuel line routing, in-tank filter

Cuts slowly

Chain pitch/gauge, bar wear, drive links

Replacement Options

Best OEM equivalent

Start with OEM references 90023Y, A226000473, A369000100, A021003390 and match the removed part before choosing a listing.

Common aftermarket option

Cross-check aftermarket listings such as Champion CJ8Y (spark plug), Stens 610-009 (fuel filter), Walbro WT-1009 (carburetor) against the OEM number and dimensions.

Best for annual tune-up

Bundle spark plug, air filter, fuel filter when servicing the Echo CS-500P at the start of the season.

Best if replacing fuel system

Compare the fuel filter, carburetor, primer bulb, fuel line kit together so line routing, bulb size, filter style, and carburetor connections match.

Best chain/bar combo

Match chain specs together, especially pitch, gauge, drive links, and bar mount details.

Best budget kit

Use kit listings only when every included part matches this model page; cheap kits often mix correct headline parts with wrong bulbs, lines, or gaskets.

FAQ

Does this fit other Echo models? Use this page for the exact Echo CS-500P unless a manual, dealer listing, or removed part confirms another model.

Should I buy OEM or aftermarket parts for the Echo CS-500P? Use OEM when the part controls fuel metering, ignition, or safety. Aftermarket kits can be useful for routine filters, bulbs, plugs, and tune-up bundles when the OEM number and dimensions match.

How do I avoid ordering the wrong carburetor for the CS-500P? Match the carburetor number stamped on the removed unit, then compare linkage, choke setup, primer routing, gasket stack, and fuel-inlet direction.

What should I check before replacing fuel-system parts? Photograph the old fuel-line routing, match line diameter and filter style, and compare primer bulb size before buying a kit.

What chain details matter besides bar length? Match pitch, gauge, and drive-link count against the bar stamp, old chain, and drive sprocket. Bar length alone is not enough.

Spark Plug

OEM90023YConfidence: Medium · Source: Aftermarket catalog

Reviewed: 2026-05-20
Dimensions: 0.6mm gap

Brand	Part #
Champion	CJ8Y	Best for annual tune-upAmazonAffiliate link Some links may be affiliate links. Match the OEM number, dimensions, and model variant before buying.
NGK	BPM8Y	Best for annual tune-upAmazonAffiliate link Some links may be affiliate links. Match the OEM number, dimensions, and model variant before buying.

Air Filter

OEMA226000473Confidence: Low · Source: Aftermarket catalog

Reviewed: 2026-05-20
Variant notes: Also fits CS-501P (current successor)

Brand	Part #
No aftermarket listing is published for this part yet. Use the OEM reference and verify with a dealer or service manual before ordering.

Fuel Filter

OEMA369000100Confidence: Medium · Source: Aftermarket catalog

Reviewed: 2026-05-20
Variant notes: In-tank pickup filter; fits most Echo chainsaws and trimmers

Brand	Part #
Stens	610-009	Best if replacing fuel systemAmazonAffiliate link Some links may be affiliate links. Match the OEM number, dimensions, and model variant before buying.

Carburetor

OEMA021003390Confidence: Medium · Source: Aftermarket catalog

Reviewed: 2026-05-20
Variant notes: Walbro WT-1009; 50.2cc engine

Brand	Part #
Walbro	WT-1009	Best if replacing fuel systemAmazonAffiliate link Some links may be affiliate links. Match the OEM number, dimensions, and model variant before buying.

Recoil Starter

OEMA180001600Confidence: Low · Source: Aftermarket catalog

Reviewed: 2026-05-20

Brand	Part #
No aftermarket listing is published for this part yet. Use the OEM reference and verify with a dealer or service manual before ordering.

Primer Bulb

OEM12318139130Confidence: Medium · Source: Aftermarket catalog

Reviewed: 2026-05-20

Brand	Part #
Zama	BG-00-4	Best if replacing fuel systemAmazonAffiliate link Some links may be affiliate links. Match the OEM number, dimensions, and model variant before buying.

Fuel Line Kit

OEMV471001471Confidence: Medium · Source: Aftermarket catalog

Reviewed: 2026-05-20
Variant notes: Includes fuel pickup line and return line

Brand	Part #
Stens	115-530	Best if replacing fuel systemAmazonAffiliate link Some links may be affiliate links. Match the OEM number, dimensions, and model variant before buying.

Chain

OEMSpec-based fitmentConfidence: Low · Source: Inferred

Reviewed: 2026-05-20
Dimensions: 20", 3/8" pitch, .050" gauge, 70 drive links
Variant notes: Stock bar length; verify drive link count matches your bar

Brand	Part #
Oregon	72LPX070G	Best chain/bar comboAmazonAffiliate link Some links may be affiliate links. Match the OEM number, dimensions, and model variant before buying.

Guide Bar