Husky 261 Project

[aducomb]

Update

I took awhile for me to get back into this project so here's an update:

I took the carb apart again and soaked it in carb cleaner over night, also found the metering lever to be just a little high so it was adjusted lower and put back together. With the H needle all the way in it is still turning around 12,000 rpm.

Unfortunately I do not have a compression tester so I cannot do a pressure and vac test. An air leak was suggested as a possibility but wouldn't that cause a lean condition?

Someone also mentioned the welch plug. I haven't ever messed with taking one out, should I give it a shot?

I put a new spark plug in when I started this rebuild. I just pulled it after the saw has been sitting about 5 days and it still just a little wet and a very dark brown. Which leads me to believe the low rpm's are due to a rich carb and not a bad coil.

At this point my gut still thinks its the carb. It was also suggested that the needle seats have been damaged causing it to run rich. Is it time to go to the dealer or find a new carb? I'm hoping not. Any suggestions, what am I missing?

 

[272super]

As far as the welsh plug, see if it looks sealed. If not reseal with nail polish. You don't need to remove. A leaking welsh plug is a longshot though. With the H screw 1/2 out to all the way in,top rpm never changes? If so, it's rich for sure IF the carb is the issue. But it might not be the carb. A bad coil can do this and low compression or excessive piston skirt wear can as well. You should not have low compression with a new piston but without a test,you never know for sure. Without a compression test,you could test your squish band to see if there is an excessive amount. If all else fails,another carb might be the cure.

Now if peak rpm occurs at, say-2/3 to 1/2 turn out and goes down with the screw all the way in,then an air leak is more likely. It would also hesitate badly as it accelerates if it were lean. That does not sound like your problem,though.

 

[aducomb]

As far as the welsh plug, see if it looks sealed. If not reseal with nail polish. You don't need to remove. A leaking welsh plug is a longshot though. With the H screw 1/2 out to all the way in,top rpm never changes? If so, it's rich for sure IF the carb is the issue. But it might not be the carb. A bad coil can do this and low compression or excessive piston skirt wear can as well. You should not have low compression with a new piston but without a test,you never know for sure. Without a compression test,you could test your squish band to see if there is an excessive amount. If all else fails,another carb might be the cure.

Now if peak rpm occurs at, say-2/3 to 1/2 turn out and goes down with the screw all the way in,then an air leak is more likely. It would also hesitate badly as it accelerates if it were lean. That does not sound like your problem,though.

Peak rpm occurs with the H all the way in and does not die off so I'm leaning away from an air leak and I have confirmed that it is not the coil. I found a known good one, made the switch and the problem remains.

This is the furthest I've gone into a rebuild so while it's frustrating it's also helping me learn that without the proper tools diagnosing can be difficult. Tomorrow I will be going into town and will get a compression tester which will be able to give me more information.

Today I will be tearing down the saw again to check the condition of the cylinder, recently installed new piston, and the squish. Thanks for all the help so far guys, AS is a great resource for those seeking more information!

 

[272super]

One other thing to check is your throttle link and whether it is opening the throttle all the way. They can bend over time and it can prevent the throttle butterfly from opening all the way. A longshot sure,but something to check.