Mechanical issue with Pioneer 1200A carb

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Yavar

Yavar

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Hood day, everyone. Glad to join this group.

Heres my question:. On my Pioneer 1200A, the throttle linkage is fine but the part on the carburetor won't move more than a millimeter (If I disconnect the linkage, the trigger has normal movement but when the linkage is connecting, the carburetor part that vonnects to the linkage won't move). I disconnected the linkage going up to the carburetor and tried to move it with my fingers without success. I have never actually fired up this chainsaw. It was a gift and I just wanted to clean it up and that's when I noticed the issue. Any advice would be greatly appreciated. Thanks.
 

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cscltd

cscltd

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The throttle rod looks like it is bent excessively at 90* points which lessens travel of butterfly. Bent them a bit straighter may cure that
 
Yavar

Yavar

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The throttle rod looks like it is bent excessively at 90* points which lessens travel of butterfly. Bent them a bit straighter may cure that
Hi, I removed the carb and found what appears to be corrosion. The butterfly won't budge at all and the previous attempts to force the trigger have caused a small play between the brass and the other rotating part that connects to the linkage.I even loosened the two screws that would potentially let me "slide" the "shaft" that goes through the butterfly but didn't help; its jammed shut. The play is marked with an "x" in the second picture. Will try penetrating oil for a few days. Any other suggestions are welcome:)
 

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hotshot

hotshot

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Just soak it in PB Blaster spray & seal it up in a ziploc bag for a few days. Brass that’s not coated (ie with teflon) or kept oiled will corrode the aluminum if moisture is present.

Lucky those Tillotson HS44 carbs are easy to work on & commonly for sale on the auction sites if you need to replace it.
 
Yavar

Yavar

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Just soak it in PB Blaster spray & seal it up in a ziploc bag for a few days. Brass that’s not coated (ie with teflon) or kept oiled will corrode the aluminum if moisture is present.

Lucky those Tillotson HS44 carbs are easy to work on & commonly for sale on the auction sites if you need to replace it.
Thanks! I will do that. Not in a rush, anyway. I am glad that I was able to find this forum. In about a year or earlier, I plan to move out into the country so I might actually use this saw. I love the all metal design. The compression seems pretty good and the ignition sparks.Tge chain and associated hardware has minimal rust and gives freely. I have basically coated everything with oil, regardless.
 
telecasterfool

telecasterfool

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Keep at it - patience is your friend. I bought a 1200a that looked like it had been dragged behind a truck. It didn't take much to fix and it still gets a lot of work done. you will probably need fuel and oil lines, fuel filter, carb kit, and maybe a fuel cap with a duck valve. good luck and enjoy.
 

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