Current Carburetor Settings - Husqvarna 440

See main issue: OverheatStalling README

📏 Current Carburetor Settings (As of 2026-03-23 12:59 PM)

All measurements from fully seated (lightly tightened, not forced)

Screw	Position	Direction
T (Throttle)	5 turns out	Higher idle speed
L (Low Speed)	2¼ turns out	Rich mixture
H (High Speed)	1¾ turns out	Rich mixture

📊 Analysis vs Factory Defaults

Screw	Factory Default	Current Setting	Difference
L	1¼ - 2¼ turns	2¼ turns	At upper limit (rich)
H	1¼ - 1½ turns	1¾ turns	0.25-0.5 turns richer (likely culprit)
T	Adjust for idle	5 turns	Very high idle setting

Key Finding: H screw is set richer than factory default range, which would cause the rich-when-hot stalling issue.

🔧 Recommended Adjustment Plan

Step 1: Lean Out H Screw

Turn H screw clockwise to 1½ turns (within factory range)
Test run - see if stalling issue improves

Step 2: Fine-tune L Screw (if needed)

L is already at upper factory limit
If still stalling, turn L clockwise to 2 turns (slightly leaner)

Step 3: Adjust T Screw

5 turns is very high for idle
Turn T counter-clockwise until smooth idle with chain NOT rotating
Likely needs to be 2-3 turns out, not 5

📝 Testing Notes

After adjustments, document:

Does it still stall when warm?
How many minutes until stalling (if it does)?
Does it restart without cooling?
Final settings that work

🔧 Adjustment Procedure (2026-03-23)

Recommended Steps:

Let saw cool completely (1+ hour cooling period from previous stall)
Turn H screw clockwise from 1¾ to 1½ turns (leaner mixture)
Start the saw and let it warm up
Adjust T screw counter-clockwise until chain doesn't rotate at idle (likely 2-3 turns)
Test run for 10+ minutes to see if stalling is fixed
If still stalls:
- Fine-tune H in 1/8 turn increments (clockwise = leaner)
- Fine-tune L clockwise to 2 turns if needed
Document final working settings

Important: Make small adjustments (1/8 turn) and let saw stabilize 30 seconds between turns. H screw affects high-speed mixture - give it throttle to feel the difference.

📅 Revision History

Date	Change
2026-03-23 13:29	Adjustment procedure documented - H to 1½ turns, T to 2-3 turns for test

OverheatStalling README - Issue documentation
Main Project README - Overall chainsaw info

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