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

Mercruiser 4.3 started making intermittent screaming sound

Customer Question

Mercruiser 4.3 started making intermittent screaming sound at low speed just after refueling. Oil was at end of dipstick. Added oil and verified that noise was from engine and not belt. Progressively worse so we got towed home...
JA: Sometimes things that you think will be really complicated end up being easy to fix. The Marine Mechanic I'm going to connect you with knows all the tricks and shortcuts. Is there anything else important you think the Marine Mechanic should know?
Customer: Engine was also low on oil at beginning of season and was topped off. Boat only used a few times this season.
Submitted: 1 year ago.
Category: Boat
Expert:  Tan replied 1 year ago.

Hello. My name is Tan.

Remove the belt does the noise stop?

This could be any of the rotating components on the front of the engine. Possibly circulation pump or alternator. If this is a serpentine belt idler pulley. Any of these can cause squealing. Removing the belt will at least verify if it is engine or not.

Post back with findings and questions.

Related Boat Questions