40hp 2 stroke starting problems!!!

[camarostripes96]

ok i just bought a 2002 pontoon with a 2002 40 hp 2 stroke mercury and the boat and motor has 9 hrs on it all, the older man barely used it , well it did sit for a while and the gas was bad in the gas tank and i cleaned it out and put a new primer bulb with new gas line and it will crank up with no problem but it runs for about 5 seconds and dies, and i will crank it again and run for about 5 seconds and die again. It will do this over and over, does anyone know what i need to do or is wrong?
thanks

 

[hamit59]

Re: 40hp 2 stroke starting problems!!!

Looks like you have already have a good start the work that needs to be done .On any motor that has sat unused for any time you need to Go throw the whole fuel system: Ie :fuel lines, fuel pump, Clean your tanks, and last but not least clean a rebuild the carbs

Next thing that I would do is replace the lower lube and the water pump.
Do a good cleaning and lube on the whole motor with a good marine grease.

If you don't have a book on your motor it's well it worth it's weight

 

[MadProps]

Re: 40hp 2 stroke starting problems!!!

squirt fuel in the throats of the carbs as it is about to die

If it picks up the rpm I think your low speed circuits are dirty, and require carb overhaul

good luck

 

[Silvertip]

Re: 40hp 2 stroke starting problems!!!

Don't be squirting fuel into the carbs -- sneeze can cause a fire. Simply push the key in when the engine begins to die. If it picks up you have a fuel delivery problem that is probably due to a number of things such as a weak fuel pump, a clogged screen on the fuel pickup tube in the tank, a sticky anti-siphon valve on the fuel tank (if its a built-in tank), or carbs that need rebuilding.

 

[camarostripes96]

Re: 40hp 2 stroke starting problems!!!

oh ok , so how hard is it to rebuild the carb and clean it? also how do i change out the lower unit fluid?

 

[Silvertip]

Re: 40hp 2 stroke starting problems!!!

How hard it is to do any job on an outboard, or any other engine for that matter depends entirely on your capabilities. For an experienced tech rebuilding carbs is a day in and day out operation that takes very little time. Changing lower unit lub is a 1/2 hour process for even a novice. But your questions are all answered in a service manual specific to your engine. The proper manual saves you time and helps prevent mistakes that can be very costly if a procedure is not done correctly. As for chaning the lower unit lub, you remove the upper vent plug and the lower drain plug and let the lub drain into a pan. If you see water come out you have a seal problem that needs to be addressed. You refill the lower unit from the bottom until lube dribbles out the vent. Insert the vent plug, then the drain plug. Carbs need to be totally disassembled, soaked in carb cleaner, blown out with compressed air and reassembled with new kits and properly adjusted when finished. If you need more instruction than that, you really need a manual.