BigDeWitt88
ArboristSite Lurker
I am working on a Stihl 026 for a friend.
The symptom: starts and runs fine. Has power for about 15 to 25 minutes (varies) while in the cut. After the above time has elapsed, the saw will die. It will not restart and run again until it cools down. Then after a restart and more work it will quit again.
What I have done to fix the issue:
I started by checking the spark arrestor screen which was clear. Checked for good spark which it has. It appears to have decent compression, however, my compression gauge is currently broken so I am not sure where it is running but it feels good when you pull it over. I began checking the fuel system. There was no fuel filter on the fuel line and the fuel line was frail and cracking. So I put a new fuel line and filter on the saw. I took the carburetor apart and cleaned it. It had a lot of junk caught in the screen. Put it all back together and it ran like **** still. So I rebuilt the carburetor. Still runs like ****. I thought maybe it was leaning out. I did a leak down test blocking off the exhaust and intake ports. I left the spark plug in. I pumped air through the impulse line and also did a vacuum test. It doesn't have an air leak. All of the jug bolts are tight. I took the muffler off and checked the piston and cylinder wall on the intake side as you can't see the cylinder wall on the exhaust side from the exhaust side of the jug. The piston looked as if it possibly had the slightest bit of scoring. It is barely visible to the naked eye but under a strong light it can be seen. I don't feel like that's the issue. I have fixed a lot of small engines over the years and have never had this problem. Please any advice would be great because I am about to set the damn thing ablaze.
The symptom: starts and runs fine. Has power for about 15 to 25 minutes (varies) while in the cut. After the above time has elapsed, the saw will die. It will not restart and run again until it cools down. Then after a restart and more work it will quit again.
What I have done to fix the issue:
I started by checking the spark arrestor screen which was clear. Checked for good spark which it has. It appears to have decent compression, however, my compression gauge is currently broken so I am not sure where it is running but it feels good when you pull it over. I began checking the fuel system. There was no fuel filter on the fuel line and the fuel line was frail and cracking. So I put a new fuel line and filter on the saw. I took the carburetor apart and cleaned it. It had a lot of junk caught in the screen. Put it all back together and it ran like **** still. So I rebuilt the carburetor. Still runs like ****. I thought maybe it was leaning out. I did a leak down test blocking off the exhaust and intake ports. I left the spark plug in. I pumped air through the impulse line and also did a vacuum test. It doesn't have an air leak. All of the jug bolts are tight. I took the muffler off and checked the piston and cylinder wall on the intake side as you can't see the cylinder wall on the exhaust side from the exhaust side of the jug. The piston looked as if it possibly had the slightest bit of scoring. It is barely visible to the naked eye but under a strong light it can be seen. I don't feel like that's the issue. I have fixed a lot of small engines over the years and have never had this problem. Please any advice would be great because I am about to set the damn thing ablaze.
