Hey small engine shade tree mechanics and professionals -
I have a 2.5 year old Makita trimmer with low hours - maybe 10. Its a 4 cycle, separate gas/oil, not a 4-mix. This year it developed a problem where it became hard to restart hot and if i got it going, it would idle out and die. When cold, it starts first pull, it idles well when cold and has amazing power. If i shut it off for 15-20 min, restarting is only made by holding down the throttle and pulling. If i get it going then, it will then idle out. Things I have done so far:
1. Adjusted idle screw - I have a tachometer
2. Adjusted/checked valve lash - they are perfect
3. Spark arrester was removed day one of ownership
4. Oil is clean
5. Air filters are clean
6. Carb body and related gaskets appear tight and clean
7. I metered resistance of coil its within spec. I have not done this when its hot, will this make a difference?
8. Thought it was venting problem, removing gas gap - no improvement
9. Took it to local mechanic, who said it was idle screw wiggling and getting out of adjustment, so I put some loctite on the screw to hold it down. I used low strength locktite, but it made no difference for hot restart problems.
10. NEw spark plug with correct gap made no difference.
I'm at a loss for what it could be. I'm close to buying a new carb, but they are like $50 and I really don't think its the carb. The carb is not adjustable since its a 4 cycle. Any other suggestions for me? I love this trimmer, but its giving me a headache with this problem. This is a professional model and cost about $300 new, so i'd like to fix it.
Any ideas? Thanks so much
I have a 2.5 year old Makita trimmer with low hours - maybe 10. Its a 4 cycle, separate gas/oil, not a 4-mix. This year it developed a problem where it became hard to restart hot and if i got it going, it would idle out and die. When cold, it starts first pull, it idles well when cold and has amazing power. If i shut it off for 15-20 min, restarting is only made by holding down the throttle and pulling. If i get it going then, it will then idle out. Things I have done so far:
1. Adjusted idle screw - I have a tachometer
2. Adjusted/checked valve lash - they are perfect
3. Spark arrester was removed day one of ownership
4. Oil is clean
5. Air filters are clean
6. Carb body and related gaskets appear tight and clean
7. I metered resistance of coil its within spec. I have not done this when its hot, will this make a difference?
8. Thought it was venting problem, removing gas gap - no improvement
9. Took it to local mechanic, who said it was idle screw wiggling and getting out of adjustment, so I put some loctite on the screw to hold it down. I used low strength locktite, but it made no difference for hot restart problems.
10. NEw spark plug with correct gap made no difference.
I'm at a loss for what it could be. I'm close to buying a new carb, but they are like $50 and I really don't think its the carb. The carb is not adjustable since its a 4 cycle. Any other suggestions for me? I love this trimmer, but its giving me a headache with this problem. This is a professional model and cost about $300 new, so i'd like to fix it.
Any ideas? Thanks so much
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