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 Dominick Your Own Question
Dominick, Marine Mechanic
Category: Boat
Satisfied Customers: 1009
Experience:  25 Years Experience as Mechanic, 20 Yrs Boat Yard Owner/Mechanic, Factory Certified
Type Your Boat Question Here...
Dominick is online now
A new question is answered every 9 seconds

Motor will not rev past 500rpm under load but revs fine in

Customer Question

motor will not rev past 500rpm under load but revs fine in nutral
Submitted: 2 years ago.
Category: Boat
Expert:  Jason replied 2 years ago.
Good morning my name is ***** ***** I will be helping you today. What engine do you have specifically. Do you have a year/make/model or serial number on it so I can identify it?
Customer: replied 2 years ago.
2000 mercury 115 ob
Customer: replied 2 years ago.
(Posted by JustAnswer at customer's request) Hello. I would like to request the following Expert Service(s) from you: Live Phone Call. Let me know if you need more information, or send me the service offer(s) so we can proceed.
Expert:  Jason replied 2 years ago.
Do you have the serial number on the engine? If not, is it 2 stroke, 4 stroke, carbureted or fuel injected?
Customer: replied 2 years ago.
2stroke carbureted oil injected
Expert:  Jason replied 2 years ago.
Got it. What is the history on the engine? How old is the fuel. Has it been sitting a long time?
Expert:  Jason replied 2 years ago.
It looks like you read my reply and logged off. Was this something you still needed help with?
Expert:  Tan replied 2 years ago.
Hello. My name is***** engine not performing under load is usually a spark or fuel related issue. We need to start out with a spark and compression test. The compression must 90+ psi with no more than 15% difference between cylinders. The spark must jump a 7/16" gap on a spark gap tester. Post back with you findings and we can continue.

Related Boat Questions