High Altitude Rejetting

[TConnolly10]

Hi everyone, I own a 1998 Yamaha 15hp 2 stroke and recently moved from south Florida to Colorado. I can’t get the engine to run right, and my understanding is that I may just have to change out the jets in the carb to jets for high altitude. Does anyone know the part numbers for these? I’m having trouble finding them. I appreciate any help you can provide!

 

[boscoe99]

www.jetsrus.com

 

[Sea Rider]

At which high altutude will the motor be working at ? if not that high a prop maximization for the motor to run towards its max wot rpm range factory stated as loaded will work. If very high will need a carb rejet along a less pitch prop to compensate high altitude boating.

Happy Boating​

 

[TConnolly10]

At which high altutude will the motor be working at ? if not that high a prop maximization for the motor to run towards its max wot rpm range factory stated as loaded will work. If very high will need a carb rejet along a less pitch prop to compensate high altitude boating.

Happy Boating​

Thank you for the reply! I will definitely look into a new prop, but right now I’m working to get the new jets because I’ll be around 7,500-9,000 ft

 

[TConnolly10]

www.jetsrus.com

Thank you! I’m working with them now to identify the correct parts I need.

 

[99yam40]

yep less O2 up higher so less fuel needed to burn properly.
this also means less HP, so it will not be able to push the prop you had if it was chosen correctly for sea level