Chainsaw

Stihl MS 500i

2-Stroke

The Stihl MS 500i is a 79.2cc 2-stroke professional chainsaw and the first production chainsaw from any manufacturer with direct electronic fuel injection — there is no carburetor to rebuild. The maintenance profile shifts accordingly: fuel filter cleanliness is critical (injectors are contamination-sensitive), but carburetor diaphragm and needle/seat replacement are eliminated entirely. The MS 500i accepts 20" to 32" guide bars and delivers consistent power delivery in any orientation and across altitude changes. Aimed at professional loggers who want peak performance without altitude-related richening.

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, Recoil Starter, Chain, Guide Bar
OEM References: 0000 400 7011, 1144 140 4402, 0000 350 3518, 1144 080 2100
Model Family: MS 500i
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	0000 400 7011	NGK CMR6H	Medium · 2026-05-20
Air Filter	1144 140 4402	OEM 1144 140 4402	Low · 2026-05-20
Fuel Filter	0000 350 3518	OEM 0000 350 3518	Low · 2026-05-20
Recoil Starter	1144 080 2100	OEM 1144 080 2100	Low · 2026-05-20
Chain	25", 3/8" pitch, .050" gauge, 84 drive links	Oregon 72EXL084G	Low · 2026-05-20
Guide Bar	25", 3/8" pitch, .050" gauge	Oregon 250VXLHD025	Low · 2026-05-20

Tune-Up Kit

Common service bundle: spark plug, air filter, fuel filter.

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 Stihl MS 500i, 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.
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

Cuts slowly

Chain pitch/gauge, bar wear, drive links

Replacement Options

Best OEM equivalent

Start with OEM references 0000 400 7011, 1144 140 4402, 0000 350 3518, 1144 080 2100 and match the removed part before choosing a listing.

Common aftermarket option

Cross-check aftermarket listings such as NGK CMR6H (spark plug), Oregon 72EXL084G (chain), Oregon 250VXLHD025 (guide bar) against the OEM number and dimensions.

Best for annual tune-up

Bundle spark plug, air filter, fuel filter when servicing the Stihl MS 500i at the start of the season.

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 Stihl models? Use this page for the exact Stihl MS 500i unless a manual, dealer listing, or removed part confirms another model.

Should I buy OEM or aftermarket parts for the Stihl MS 500i? 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.

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

OEM0000 400 7011Confidence: Medium · Source: Aftermarket catalog

Reviewed: 2026-05-20
Dimensions: 0.7mm gap
Variant notes: 10mm thread — do not substitute BPMR7A (14mm thread)

Brand	Part #
NGK	CMR6H	Best for annual tune-upAmazonAffiliate link Some links may be affiliate links. Match the OEM number, dimensions, and model variant before buying.
Champion	RZ7C	Best for annual tune-upAmazonAffiliate link Some links may be affiliate links. Match the OEM number, dimensions, and model variant before buying.

Air Filter

OEM1144 140 4402Confidence: Low · Source: Aftermarket catalog

Reviewed: 2026-05-20
Variant notes: HD2 filter; also fits MS 651, MS 661 C-M

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

OEM0000 350 3518Confidence: Low · Source: Aftermarket catalog

Reviewed: 2026-05-20
Variant notes: Orange in-tank pickup body fuel filter

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.

Recoil Starter

OEM1144 080 2100Confidence: 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.

Chain

OEMSpec-based fitmentConfidence: Low · Source: Inferred

Reviewed: 2026-05-20
Dimensions: 25", 3/8" pitch, .050" gauge, 84 drive links
Variant notes: Stock bar length; verify drive link count matches your bar

Brand	Part #
Oregon	72EXL084G	Best chain/bar comboAmazonAffiliate link Some links may be affiliate links. Match the OEM number, dimensions, and model variant before buying.

Guide Bar