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SKU:
NLT1Q02583
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Carburetor for Stihl BR320 BR340 BR380 BR400 BR420 SR320-SR420 4203-120-0601
$24.99
In Stock
$24.99
Sale price
$24.99
Regular price
Aftermarket carburetor replacing Stihl 4203-120-0601 for compatible BR320-BR420 backpack blowers and SR320-SR420 sprayer/blowers.
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Compatible Models
We do our best to list all compatible models. Although this may be the part you need, your exact model may not appear below.
Compatible equipment / model
- Stihl BR320
- Stihl BR340
- Stihl BR340L
- Stihl BR380
- Stihl BR400
- Stihl BR420
- Stihl BR420C
- Stihl SR320
- Stihl SR340
- Stihl SR380
- Stihl SR400
- Stihl SR420
Product Overview
A blower that only runs on choke, surges, stalls under throttle, floods, or leaks fuel may have hardened diaphragms or blocked internal passages after old fuel, lines, filter, and ignition are checked. This assembled carburetor is a straightforward route back to reliable starting and throttle response.
Several Walbro and Stihl revisions appear in this family. Match the number or carb body, throttle and choke shafts, impulse opening, fuel nipples, and linkage positions. Replace stale fuel and inspect the fuel line and tank vent so the same contamination does not reach the new carburetor.
Key Features & Performance
- Complete replacement carburetor body
- Correct linkage layout for listed BR/SR applications
- Cross-references multiple Stihl carburetor revisions
- Addresses worn diaphragms and internal fuel-metering faults
- Ready for application-specific idle and mixture verification
Replaces Part Numbers
- 4203-120-0601
- 4203-120-0603
- 4203-120-0605
- 4203-120-0607
- Walbro HD-4A
- Walbro HD-4B
- Walbro HD-13B
Common Uses
- Repairing a blower that will run only with choke
- Replacing a carburetor with recurring fuel leakage
- Correcting surging or bogging traced to fuel metering
- Returning a stored blower to service after stale-fuel damage
Technical Specifications
- Product Type: Diaphragm Carburetor
- Compatible Brand: Stihl
- Equipment: Backpack blowers and sprayer/blowers
- Primary Reference: 4203-120-0601
- Condition: New
- Replacement Type: Aftermarket
Installation & Fitment
- Drain stale fuel and disconnect the spark-plug lead
- Photograph throttle, choke, impulse, and fuel-line routing
- Replace brittle fuel line and the filter before attaching the new carburetor
- Use sound intake gaskets and verify the impulse passage is open
- Start with factory adjustment guidance and tune only with the correct tachometer and procedure
Compatibility Notice
Northline Parts does its best to list all known compatible models, but the correct part may fit an application not shown.
Model, production date, serial number, engine or equipment configuration, installed options, and previous repairs can affect fitment. Compare the original part, identifying numbers, dimensions, connections, and mounting details before purchase.
Frequently Asked Questions
Q: Why will my Stihl blower run only on choke? A: A lean fuel supply from a dirty carburetor, cracked line, blocked filter, tank vent, or intake leak is common. Diagnose before replacing parts.
Q: Does this cover SR sprayer/blower models too? A: Yes. The listed fitment includes SR320, SR340, SR380, SR400, and SR420 when the original carburetor matches.
Q: Can I install it with old fuel lines? A: Inspect them closely. Cracked or softened lines can leak air or shed debris into the replacement carburetor.
Q: Will it arrive perfectly adjusted? A: Final idle and mixture settings can vary by model, fuel, altitude, and engine condition. Follow the equipment service procedure.
Part Summary
keywords: Stihl 4203-120-0601 carburetor, BR420 carb replacement, BR400 runs only on choke, BR320 blower carburetor, SR420 fuel system repair, Walbro HD-4A replacement, aftermarket Stihl backpack blower carb
Brand names, model numbers, and reference part numbers are used for identification and compatibility purposes only. Verify the original component, dimensions, and application before purchase.