juicer
New Member
I'm posting to share the problem I found causing my saw not to work and no other help post I've read had this as a likely cause. As its happened to me,its real world.
I run a stihl MS170 to cut firework and bought and further cheap damaged one on fleabay to fix up and take apart to learn, so as not to wreck the first one. It was sold as running butsome parts needed replaced, such as the handle which was broken. I suspect a drop or car drove over it.
I replaced the handle, new fuel line and filter. New pull cord, exhaust and visually had piston checked and looks fine.
I could only get it to start by pouring fuel mix direct into cylinder. It would run high revs and die when trigger released.
I had spark, compression(130psi) tested and some fuel as it ran until I removed finger.
Had a guy look at it and he thought the cylinder was cracked at the bottom just , I thought it was a casting mark myself.......
Anyway I tore her down and noticed 3 of the bolts holding the sump on, where half screwed out! Sump was not screwed tightly to cylinder. There was the air leak. These bolts are not the same one holding the engine to the frame. So there is a cause you don't really see in the average cause list.
John
Belfast. UK.
I run a stihl MS170 to cut firework and bought and further cheap damaged one on fleabay to fix up and take apart to learn, so as not to wreck the first one. It was sold as running butsome parts needed replaced, such as the handle which was broken. I suspect a drop or car drove over it.
I replaced the handle, new fuel line and filter. New pull cord, exhaust and visually had piston checked and looks fine.
I could only get it to start by pouring fuel mix direct into cylinder. It would run high revs and die when trigger released.
I had spark, compression(130psi) tested and some fuel as it ran until I removed finger.
Had a guy look at it and he thought the cylinder was cracked at the bottom just , I thought it was a casting mark myself.......
Anyway I tore her down and noticed 3 of the bolts holding the sump on, where half screwed out! Sump was not screwed tightly to cylinder. There was the air leak. These bolts are not the same one holding the engine to the frame. So there is a cause you don't really see in the average cause list.
John
Belfast. UK.
