CoyPatton
Veteran Member
- Joined
- Aug 10, 2015
- Messages
- 1,570
- Location
- Poplar Bluff, MO
- Tractor
- Yanmar YM2002D with Koyker 110 FEL
To check compression, you will need a compression tester. Hoye sells one for the yanmars. You can google how to run this test. You also need the compression specs for the YM240.
Unless it is your valves out of adjustment and not fully seating during compression. Then you need to figure out where your compression loss is happening.
Personally, since you know very little about the tractor history, I would start with the valve adjustment.
If it still spins freely after valve adjustment without pull the decompression lever, then it is compression test time.
Many people have a variety of ways to determine the issue of compression loss. My preferred is a cylinder leak down test. Using air pressure you look for where the air is escaping.
How does the tractor run under load after you pull start it?
Unless it is your valves out of adjustment and not fully seating during compression. Then you need to figure out where your compression loss is happening.
Personally, since you know very little about the tractor history, I would start with the valve adjustment.
If it still spins freely after valve adjustment without pull the decompression lever, then it is compression test time.
Many people have a variety of ways to determine the issue of compression loss. My preferred is a cylinder leak down test. Using air pressure you look for where the air is escaping.
How does the tractor run under load after you pull start it?