I got wind of a retired Vet squeaking out his retirement years on a SSI and his Army pension that had a Stihl chainsaw that he couldn't start. Years ago the local dealer sang him a song that his 031 was beyond hope, the parts needed were NLA, and told him that he would be better off with a new saw. Dave didn't have the resources to buy a new saw, so back home to the shed it went.
I made arrangements to pick up the saw to see what it would take to get it running again. Pulled the plug and it was showing signs that the saw was running lean. A little WD-40 down the spark plug hole, then I screwed in the compression gauge and with a few pulls I was up to 140 psi. Good enough. Checked the spark, and it was solid. Re-installed the spark plug, pulled the air cleaner (that was actually quite clean), and put some fresh 40:1 down the throat of the carb. A few pulls later it ran for a few seconds, then died.
OK..., it runs on prime. I pulled the carburetor and it was a mess inside. The metering diaphragm was as hard as a rock, but the Walbro kit for an 026 had a replacement part that matched. Pulled off the fuel inlet sign of the carb and there was a solid layer of goo on the screen and else where. A shot of carb cleaner and a light blow of compressed air and the goo was gone. The Walbro kit parts on this side didn't match the old carb, so I opted to reuse them as I hoped to get the saw back to him on Memorial Day. With the saw back together and a little fuel down the throat for good measure I filled the tank with ethanol-free premium mixed with Saber at 40:1 and on about the 6th pull if popped with the choke full on. Dropped the choke to 1/2 position and another pull had the saw running. Set the low speed jet for smooth acceleration and turned the high jet rich, then leaned to to 11,500 still on the rich side. The chain looked to have been rocked, so off the saw it came and onto the grinder. Cleaned up the rock damage and set the rakers to .025 and found a log to cut some donuts. Not as fast as a modern 50cc saw, but still cut quite well.
There's going to be a happy Vet come tomorrow.
I made arrangements to pick up the saw to see what it would take to get it running again. Pulled the plug and it was showing signs that the saw was running lean. A little WD-40 down the spark plug hole, then I screwed in the compression gauge and with a few pulls I was up to 140 psi. Good enough. Checked the spark, and it was solid. Re-installed the spark plug, pulled the air cleaner (that was actually quite clean), and put some fresh 40:1 down the throat of the carb. A few pulls later it ran for a few seconds, then died.
OK..., it runs on prime. I pulled the carburetor and it was a mess inside. The metering diaphragm was as hard as a rock, but the Walbro kit for an 026 had a replacement part that matched. Pulled off the fuel inlet sign of the carb and there was a solid layer of goo on the screen and else where. A shot of carb cleaner and a light blow of compressed air and the goo was gone. The Walbro kit parts on this side didn't match the old carb, so I opted to reuse them as I hoped to get the saw back to him on Memorial Day. With the saw back together and a little fuel down the throat for good measure I filled the tank with ethanol-free premium mixed with Saber at 40:1 and on about the 6th pull if popped with the choke full on. Dropped the choke to 1/2 position and another pull had the saw running. Set the low speed jet for smooth acceleration and turned the high jet rich, then leaned to to 11,500 still on the rich side. The chain looked to have been rocked, so off the saw it came and onto the grinder. Cleaned up the rock damage and set the rakers to .025 and found a log to cut some donuts. Not as fast as a modern 50cc saw, but still cut quite well.
There's going to be a happy Vet come tomorrow.
