whitedogone
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Little or no wear on any throttle parts or housings on this saw. I will check to see how everything "interacts" tomorrow.
066 does not have a fast idle on cold start
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I thought I would move forward with this mod using an old tank housing to show what I did to fix the choke and fast idle control settings. I made this small part using 1/8" thick hardwood. I called it a Stihl 066 switch rod shim. I imagine about any metal or hard plastic would also work, but being a woodsmith, it was easy for me to find and work with a hardwood strip:
The exact dimensions may be slightly different for your saw based on the amount of the switch rod's warp, the tank housing, the handle, etc. The idea is to shift the left end of the switch rod back, and closer to the trigger by anywhere from 1/32" to 1/16". That error and any gap is about all that it takes to cause the problem. The smallest possible shift is the best as long as the fast idle setting holds the trigger close to the handle and does not drop to slow idle. So, a few millings will likely be required to shape the part. Here is the placement of the shim as shown by the red arrow:
The semicircle notch wraps around the switch rod. The depth of this notch sets the offset of the switch rod and works similar to a bushing. You can insert the shim by simply removing the throttle rod, the air filter base, and the top of the handle temporarily. Then you can test it before reassembly and shape the notch as needed after reattaching the throttle rod and the top of the handle. Leave the air filter base off while testing.
If you get it to work, hold your horses. The air filter base when bolted on tight may now also exert sufficient pressure on the left end of the switch rod to overpower the carb's spring that resets the trigger to idle in the Run position. That can be fixed with a slight enlargement of the base in order to provide adequate clearance, directly where it rubs the switch rod. I used a small chisel to do this, but a small rotary grinder would also work. A little lube will smooth out the rotation.
So, any of you fellow 066 owners with saws that won't hold a fast idle may want to give this a try.
The exact dimensions may be slightly different for your saw based on the amount of the switch rod's warp, the tank housing, the handle, etc. The idea is to shift the left end of the switch rod back, and closer to the trigger by anywhere from 1/32" to 1/16". That error and any gap is about all that it takes to cause the problem. The smallest possible shift is the best as long as the fast idle setting holds the trigger close to the handle and does not drop to slow idle. So, a few millings will likely be required to shape the part. Here is the placement of the shim as shown by the red arrow:
The semicircle notch wraps around the switch rod. The depth of this notch sets the offset of the switch rod and works similar to a bushing. You can insert the shim by simply removing the throttle rod, the air filter base, and the top of the handle temporarily. Then you can test it before reassembly and shape the notch as needed after reattaching the throttle rod and the top of the handle. Leave the air filter base off while testing.
If you get it to work, hold your horses. The air filter base when bolted on tight may now also exert sufficient pressure on the left end of the switch rod to overpower the carb's spring that resets the trigger to idle in the Run position. That can be fixed with a slight enlargement of the base in order to provide adequate clearance, directly where it rubs the switch rod. I used a small chisel to do this, but a small rotary grinder would also work. A little lube will smooth out the rotation.
So, any of you fellow 066 owners with saws that won't hold a fast idle may want to give this a try.
Here are photos that photobucket censored above:
You may wish to visit the Power Equipment site for a recent discussion. Apparently this fast idle trouble also has hit the 650 and 660. The 661 does not seem to be experiencing it.
You may wish to visit the Power Equipment site for a recent discussion. Apparently this fast idle trouble also has hit the 650 and 660. The 661 does not seem to be experiencing it.
