I am new to boats. I have a 2011 Nitro Z6 with a 115 Merc Optimax Pro. Recently it has had issues starting. So when I start for the first time the motor will fire up then shut off instantly. Then I have to turn the key for several seconds 10-15 and it will start up and some smoke will come out it runs fine until i turn it off and let it sit for more than 20 Min then it does the same thing. If I pull up on a spot and fish for 20 min or so it will start just fine but when it sits for a while it does the same thing. Any ideas what this could be? Thanks

I'd start with the fuel filter and fuel lines

Some tech's recommend pumping the primer bulb prior to each restart due to the low quality fuel we're stuck with. A battery that is inadequate and/or not fully charged will cause problems similar to the ones you're describing as well. Might be a good time to get it into a good Merc shop and get the service up to date. Good luck!

what kind of gas are you running?

I feel like slonezp has a good suggestion on the fuel lines.  It may not be getting gas and the gas could also be bad.

With an optiMax there are some things to look at. First if you have the original fuel lines from 2011 then they need to be replaced. I just did it on my 2010 Lowe. Those lines are causing lots of trouble because they disintegrate internally. In your case you may have an inline fuel filter in your boat. You definitely have a fuel filter inside the fuel manifold/ fuel box. I say inside because some are inside and some are on the side of that manifold box.  Inside that box is a float like a carburetor and an electric fuel pump.  There is also a mechanical diaphragm pump and it could be partly your problem. This needs to go to your Mercury mechanic to be cleaned, inspected and repaired. There is no problem with you saving some money and replace your filters and fuel line yourself. It cost me about $45 for the new line to go from the tank to the engine including the new Johnson brand fuel primer bulb. I have had issues with a few brand new Merc bulbs and the aftermarket bulbs are a crap shoot.  I had two Merc dealers even suggest the Johnson ones.  So start with the simple things which should also include a new set of spark plugs. Another important thing to do is hook your boat up to a garden hose and supply water to the engine using earmuffs.  Start and idle at night and inspect around the engine and see if any of the plug wires are arcing. It should be a snap sound and a light show. It might be time to replace the spark plug wires too.

Sounds like its losing prime, idk much about that engine having not owned any outboard newer than 97 but I am a mechanic. Fuel injected I assume? If so could be a one way check valve or pressure regulator. Start with simple fuel system checks, if your not familiar with your engine call a shop. No sense in wasting a lot of time when it could be a simple 30 min fix

I am running the same rig in a 2010 model. Run a bottle of Sea Foam through it first. If you have not done it yet replace the fuel filter. The only issue I have had with mine is Coil #2 went away, easy fix.

On 5/3/2017 at 7:24 PM, lo n slo said:

what kind of gas are you running?

I was thinking the same thing....

 

OP, what ya runnin' in that bad boy?