Hi everyone, well my mm 55 tiller hasn't been running well at all. So I thought it would be time for a carb kit. It seemed pretty simple I was careful and took pics to make sure everything went back just like it came out. Well the same thing it will start and run but I cannot get any power out of it. If I squeeze the throttle it will die. On the high speed ( the screw to the top and right) I have had to screw the needle all the way in to get it to run. Also the idle adj doesn't seem to work at all. Could my filter be plugged? Plenty of spark and seems like good compression but I haven't checked it with a gauge. I can't find any cracks in the fuel lines either. I was hoping someone might of had a problem similar to this and could help me out. Well thanks and I will wait for some feedback.
stihl mm 55 tiller carb problems?????
- Thread starter gmacmopar
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reynoldston
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I have found for the cost of a new carburetor when I have a small 2 cycle engine come into my shop I replace the carburetor instead of rebuilding the old one. I also replace the fuel lines and filter. As for myself I have had very good luck in doing so. Just don't have very good luck with rebuilding them small carburetors. Still check for the plugged exhaust, I find if the exhaust is plugged you will lose high speed and power was you described but still will have low speed.
Lawnboy18
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I rebuilt the carb with success on my MM55. I was having maximum power issues. It would hit the "rev limiter" too soon so to speak. But, sometimes I just replace the carburetor. Much more simple.
reynoldston
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He said he could get a carburetor for 30 dollars. I find as a repair in my shop the cost of a repair kit and my labor its cheaper and a better job for me to replace the carburetor. If its my own equipment I would just try cleaning it without buying any parts first.
Ok, pulled the fuel lines and filter they have no cracks and the filter looks very clean and I can blow thru it easily. I even blew thru the lines with my finger plugging up the other end and no leaks. Pulled the muffler, and unscrewed the spark arrestor. Muffler was empty and fairly clean, the arrestor was very black and I could shine a flashlight thru the screen but looked like it was dirtier towards the end with the nuts on the tube. Can a guy clean the spark arrestor? If so how and what with? Or just order a new one and if that doesn't work order a new carb???????
Thanks
Lawnboy18
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Here in Canada a carb kit is 17$. A brand new carburetor is 65$ and add 15% sales tax. That is why I rebuild them if I can.
To clean the spark arrestor:
Wear cloves.
Grab a torch.
Hold the tip of the screen with a vise grip and get that screen glowing red to burn all carbon off. It's ok if the arrestor is dirty in the corners. You want the center to be clean; where the exhaust escapes.