normde2001
Elite Member
- Joined
- Mar 10, 2002
- Messages
- 4,163
Mech said:I really hope you are right about the compression. I base this on my service manual for a YM226, YM226D, YM220, and YM220D and under system tests and diagnosis (section 220-10-5) for compression pressure specification it says 568 to 639 psi specified pressure, 426 psi lower limit. A note says pressure given was taken at 1000 ft above sea level. A 3.6% reduction in gauge pressure will result for each additional 1000 ft of altitude. It goes on to say that an engine with compression pressures of 426psi or less will be hard to start and is in need of overhaul.
Is that a factory produced OEM Yanmar manual, or an I&T, or other reproduction? You would need a compression ratio of 50:1+ to get numbers like that.