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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
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I have a 300 hp It idles ok and when I try speeading up it

Customer Question

I have a 300 hp It idles ok and when I try speeading up it just bogs down
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: when I try speeding up it simply cuts out like it is only on a few cellinders
JA: Is there anything else the Marine Mechanic should be aware of?
Customer: I checked the gas, ok I looked at all the plugs some carbon, cleaned them
Submitted: 10 months ago.
Category: Boat
Expert:  Jason replied 10 months ago.

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

I Do not see any kind of model information from you. What is a 300hp? Are you working on an inboard our outboard? What is the brand/model or serial number of what you are working on?

Customer: replied 10 months ago.
call me
Expert:  Jason replied 10 months ago.

I don't even know what you are working on. I may or may not be the right person to speak with. What are you working on?

Expert:  Jason replied 10 months ago.

Are you still here?

Customer: replied 10 months ago.
Customer: replied 10 months ago.
I have a outboard direct injections
Customer: replied 10 months ago.
ok can you answer on line?
Expert:  Jason replied 10 months ago.

I still dont' know what you have. Who makes this engine? What is the model or serial number on it?

Customer: replied 10 months ago.
It is a 300 hp Yamaha direct injection, 2004 model
Expert:  Jason replied 10 months ago.

Yamaha, got it. Now what is the history on this engine? Does it sit for long periods of time? When was the last time it ran correctly? Has anything happened to it that I should know about?

Customer: replied 10 months ago.
I run it about once a week, last time I ran it it did same but after a while it would speed up ok
Customer: replied 10 months ago.
I checked for water in fuel,none I checked plugs, little carbon, cleaned ok.
Customer: replied 10 months ago.
are you still there
Expert:  Jason replied 10 months ago.

Sorry for the wait, I had to check my turkey. Yamaha HPDI engines are fairly complicated and a scan tool is required to actually do any kind of troubleshooting on it. What kinds of questions did you have for me? Have you checked engine compression, spark output, or run it on another fuel source yet?

Customer: replied 10 months ago.
looks like you can't help if you saying I need a mechanic
Customer: replied 10 months ago.
Cancel all , no need for your services