Mercury 9.9 4-stroke stops after 5 seconds

[rabrown10]

My 9.9 4-stroke mercury generally runs fine but now stops randomly. It will restart but only runs for about 5 seconds. This has happened twice this week. Between these episodes it ran fine for a couple of hours.

I have checked the oil level, drained the carb, checked the fuel and filter. Remember it ran a couple of hours after I first had the problem. Now I am back the 5 second run time.

Any thoughts

 

[Expidia]

Re: Mercury 9.9 4-stroke stops after 5 seconds

You don't say what year it is. I have the same O/B. Mines a 2005.

The first thing I would check is a fuel issue or air getting in.

Look to replace the little black O rings on each side of the fuel line. Air might be getting in at those fittings or a pin hole leak in the gas line assembly. Fuel filter if it has one might be clogged too.

A squishy feeling gas bulb in the line could be a sign of air.

I just replaced the whole assembly on another 10 year old boat we have. The whole assembly was less than $20 at Walmart. If it doesn't solve your issue just return it.

Could be a bad load of gas too or water in the gas.

 

[rabrown10]

Re: Mercury 9.9 4-stroke stops after 5 seconds

Thanks for the reply

It is a 2008.

I just drained the carb and filtered the gas in the tank-maybe got a drop of water from the carb. After a couple of pulls it started to die again and I played with the throttle (high reves) and maybe blew out somthing in the carb (water). Now it is working fine but it also worked fine yesterday - then it the problem came back! Maybe it was water in the fuel but I am concerned this intermittant problem will return. I will keep testing. Will take it in for service if I can get it to repeat.

 

[Expidia]

Re: Mercury 9.9 4-stroke stops after 5 seconds

Prob coudn't hurt to mix in a 1/4 can of dry gas in the tank. Is the bulb firm after a few squeezes. Is the tank a 2008 too?

 

[dogtagger]

Re: Mercury 9.9 4-stroke stops after 5 seconds

it does sound like water. There are some good fuel additives (though expensive) that you should add to your gas.

Good luck, and keep us posted about the solution.

 

[rabrown10]

Re: Mercury 9.9 4-stroke stops after 5 seconds

It looks like water in the fuel was the problem. I drained the carb* and filtered the fuel in the tank. I have run the engine for a couple of hours and performed many starts on one pull - running smoothly.

*Note the first time I drained the carb I just let it run dry. This time I removed the drain screw - da.

If anyone needs help on changing the damper plate on a Westerbede 55A diesel let me know. Unfortunatly I now have experience.

Thanks to all for the advice.