How JustAnswer Works:
  • Ask an Expert
    Experts are full of valuable knowledge and are ready to help with any question. Credentials confirmed by a Fortune 500 verification firm.
  • Get a Professional Answer
    Via email, text message, or notification as you wait on our site.
    Ask follow up questions if you need to.
  • 100% Satisfaction Guarantee
    Rate the answer you receive.
Ask Curtis B. Your Own Question
Curtis B.
Curtis B., Technician
Category: Small Engine
Satisfied Customers: 26026
Experience:  have worked on and around most engine models for 35 yrs./Polaris ATV expert
30244710
Type Your Small Engine Question Here...
Curtis B. is online now
A new question is answered every 9 seconds

What size jet and adjustments 13hp above 5000ft

Customer Question

what size jet and adjustments for gx390 13hp above 5000ft
Submitted: 9 months ago.
Category: Small Engine
Expert:  Curtis B. replied 9 months ago.

Full model number? GX390 ?????? the parts book will show the various main jet sizes, and you want a smaller jet for high altitude.

Expert:  Curtis B. replied 9 months ago.

Only adjustment will be the idle screw, and is set while running for best idle.

Customer: replied 9 months ago.
my parts and service manual tells me only to consult an expert ie you for high altitude use I am still at square one ?
Expert:  Curtis B. replied 9 months ago.

Give me the full engine model number. I have to pick right engine.

Expert:  Curtis B. replied 9 months ago.

See # ***** for jets. in lower link. I picked random engine.

Customer: replied 9 months ago.
thank you I will try a smaller main jet​
Expert:  Curtis B. replied 9 months ago.

Thank you. Please accept and rate to close

Expert:  Curtis B. replied 9 months ago.

Question still shows open.Please accept to close.