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 Tan Your Own Question
Tan, MerCruiser Certified Technician
Category: Boat
Satisfied Customers: 10979
Experience:  40 yrs. experience with complete engine repairs both inboard/outboard and MerCruiser Certified Technician.
Type Your Boat Question Here...
Tan is online now
A new question is answered every 9 seconds

I have 1993 4.3 OCM Cobra engine engine is cracking but

Customer Question

I have 1993 4.3 OCM Cobra engine engine is cracking but doesnt start when I use the start flu spray I spray inside carburetor engine start and shut off
Submitted: 1 year ago.
Category: Boat
Expert:  Tan replied 1 year ago.

Hello. My name is Tan.

This may take more then one reply to solve your issue.

What I think is going on here is the inlet needle in the carburetor is stuck closed not allowing fuel into the carburetor.

Has the engine been sitting for a while?

Loosen the fuel line connected to the carburetor and crank engine do you have fuel at the fitting?

Use a shop towel under the fitting to catch any fuel that leaks. If fuel at the fitting then the carburetyor is clogged up with old fuel residue. This will require removal, disassembly and cleaning of the carburetor. Install a carb kit and you should be good to go.

Now if you have no fuel at the carb fitting we will have to do some more checking.

Post back with questions and findings.

Customer: replied 1 year ago.
Hi . I did what everything you say boat was running two days ago. Is still some problem I think I have wiring Problem is there any safety switch or fuses for fuel. If you have any wiring diagram that may be help me. Thanks.
Expert:  Tan replied 1 year ago.

The problem isn't electrical if the engine runs when you squirt starting fluid in the carb. That tells us you have spark.

Do you have fuel at the carb fitting when cranking? You could still have debris in the carb blocking the inlet needle.

Check for voltage at the ignition coil purple/black wire key on this will verify you have ignition.

Here is a wiring diagram.

Related Boat Questions