John Loper II
88 lines
2.7 KiB
Markdown
88 lines
2.7 KiB
Markdown
# Current Carburetor Settings - Husqvarna 440
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> **See main issue:** [OverheatStalling README](./README.md)
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## 📏 Current Carburetor Settings (As of 2026-03-23 12:59 PM)
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**All measurements from fully seated (lightly tightened, not forced)**
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| Screw | Position | Direction |
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|-------|----------|-----------|
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| **T (Throttle)** | 5 turns out | Higher idle speed |
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| **L (Low Speed)** | 2¼ turns out | Rich mixture |
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| **H (High Speed)** | 1¾ turns out | Rich mixture |
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## 📊 Analysis vs Factory Defaults
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| Screw | Factory Default | Current Setting | Difference |
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|-------|-----------------|-----------------|------------|
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| **L** | 1¼ - 2¼ turns | 2¼ turns | At upper limit (rich) |
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| **H** | 1¼ - 1½ turns | 1¾ turns | **0.25-0.5 turns richer** (likely culprit) |
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| **T** | Adjust for idle | 5 turns | Very high idle setting |
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**Key Finding:** H screw is set richer than factory default range, which would cause the rich-when-hot stalling issue.
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## 🔧 Recommended Adjustment Plan
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### Step 1: Lean Out H Screw
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1. Turn H screw **clockwise** to 1½ turns (within factory range)
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2. Test run - see if stalling issue improves
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### Step 2: Fine-tune L Screw (if needed)
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1. L is already at upper factory limit
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2. If still stalling, turn L **clockwise** to 2 turns (slightly leaner)
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### Step 3: Adjust T Screw
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1. 5 turns is very high for idle
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2. Turn T **counter-clockwise** until smooth idle with chain NOT rotating
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3. Likely needs to be 2-3 turns out, not 5
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## 📝 Testing Notes
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**After adjustments, document:**
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- Does it still stall when warm?
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- How many minutes until stalling (if it does)?
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- Does it restart without cooling?
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- Final settings that work
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## 🔧 Adjustment Procedure (2026-03-23)
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**Recommended Steps:**
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1. **Let saw cool completely** (1+ hour cooling period from previous stall)
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2. **Turn H screw clockwise from 1¾ to 1½ turns** (leaner mixture)
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3. **Start the saw** and let it warm up
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4. **Adjust T screw counter-clockwise** until chain doesn't rotate at idle (likely 2-3 turns)
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5. **Test run for 10+ minutes** to see if stalling is fixed
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6. **If still stalls:**
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- Fine-tune H in 1/8 turn increments (clockwise = leaner)
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- Fine-tune L clockwise to 2 turns if needed
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7. **Document final working settings**
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**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.
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## 📅 Revision History
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| Date | Change |
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|------|--------|
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| 2026-03-23 13:29 | Adjustment procedure documented - H to 1½ turns, T to 2-3 turns for test |
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---
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## 🔗 Related
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- [OverheatStalling README](./README.md) - Issue documentation
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- [Main Project README](../README.md) - Overall chainsaw info
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