what is the lowest compression reading acceptable for a 98 yamaha 70BETO outboard
Make (of engine): yamaha
Model (of engine): 70BETO
Usually they will be around 120 psi but it matters more that each cylinder is within 10% of each other any more and its considered to have damage to the piston, rings, or cylinder. example If #1 cylinder is 120 psi #2 is 115 and number 3 is 100 psi your looking at a problem on cylinder 3
so a reading of 116 psi across all cylinders would be acceptable for a motor of that age
Hello, I'm Mike.I'm happy to help you today. Please post back to this thread for any questions or concerns, either before or after payment.Yes 116 is fine.You need a minimum of 100# XXXXX combustion.
28 years Certified Marine Technician and past FL State Certified teaching degree