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 fires but stops when starter disengages, it fires when

Customer Question

motor fires but stops when starter disengages
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. Tell me a bit more about what's going on so the Marine Mechanic can help you best.
Customer: it fires when u turn the switch,, but wont run
JA: Is there anything else the Marine Mechanic should be aware of?
Customer: not as far as i know,,new gas .new fuel filter,,new pump bulb
Submitted: 11 months ago.
Category: Boat
Expert:  Jason replied 11 months ago.

Hello my name is ***** ***** am I speaking with?

I don't see any kind of year or model information, what are you working on?

Customer: replied 11 months ago.
2003 mercury 25 hp outboard
Expert:  Jason replied 11 months ago.

All Mercurys are cataloged by serial number, do you happen to have that number handy? If not, is this just a basic twin cylinder single carb 2 stroke model?

Customer: replied 11 months ago.
Customer: replied 11 months ago.
mix oil with gas
Expert:  Jason replied 11 months ago.

Got it.

Pull the key switch out and disconnect the black with a yellow stripe wire and let me know if it starts or does the same thing. If it does start, make sure you have water hooked up to the engine because you won't be able to shut it off until you reconnect that black/yellow wire. Also, there will be voltage on it so don't touch any bare wire.

Customer: replied 11 months ago.
Customer: replied 11 months ago.
did same thing
Expert:  Jason replied 11 months ago.

What is the history on this engine, when did it last start and run correctly? How old is the fuel itself?

Customer: replied 11 months ago.
last november< new fuel,,new gas line,,new filter,,new battery
Expert:  Jason replied 11 months ago.

Do you have any starting fluid so we can see if the engine will stay running longer on that?

Customer: replied 11 months ago.
tried that ,,does same
Customer: replied 11 months ago.
may run a few seconds longer,
Customer: replied 11 months ago.
its like the starter kicks out to soon
Expert:  Jason replied 11 months ago.

This is going to be a process of elimination. The compression and spark output need to be tested with a compression gauge and a timing light. Is that something you can do?

Customer: replied 11 months ago.
dont know,, if the auto parts atore has thim i can borrow thim
Expert:  Jason replied 11 months ago.

We need to see what the engine has for compression, and then see if it's output spark on both cylinders or not. This will get us pointed in the right direction. The starter is not the issue, the engine can be rope started if necessary (and if it was running correctly). Let me know how you make out with the compression and spark testing.

Customer: replied 11 months ago.
i used to rebuild motors in cars,,so i can use the tools
Expert:  Jason replied 11 months ago.

Sounds good, let me know how you make out.

Related Boat Questions