Help! 2003 Mercury 5hp

[chunkachange]

I have a 2003 Mercury 5 hp outboard. It was run very little by former owner and then put in storage. I cant get it to run except when I choke it, and then it runs about 6 seconds and quits. Getting gas to carb, pump works fine, bowl fills up, etc. Pulled carb and reed valve looks seated and brand new. There is a lot of smoke when it starts and lots of oil slick in the barrel after starting it 5 or 6 times. I use new gas and Quicksiver 2 cycle oil 50:1 ratio. <br /> Can anybody give me some insight as to why this motor wont run? Thanks.....Chunk

 

[rickdb1boat]

Re: Help! 2003 Mercury 5hp

Hi Chuck and Welcome,<br /><br />

It was run very little by former owner and then put in storage

Carb needs cleaning and rebuild. After sitting for a while they get gummed up on the inside. No big deal on that motor if you have a Manual to lead you through it. The slick in the barrel is normal...

 

[chunkachange]

Re: Help! 2003 Mercury 5hp

Rick, I wish that was the problem. However, I have already cleaned the carb and thats was not the problem. Gas gets to the carb, it is just not being sucked into the engine. Any suggestions? Thanks, Chunk

 

[steam_mill]

Re: Help! 2003 Mercury 5hp

How did you clean the carb. Sounds like low speed jet is clogged and/or it is running lean because it seems to run when you choke.

 

[chunkachange]

Re: Help! 2003 Mercury 5hp

Steam, I will check the carb again to be sure there is nothing amiss concerning the low speed jet. Thanks....Chunk

 

[gss036]

Re: Help! 2003 Mercury 5hp

Check to make sure the exhaust port is not gummed up too bad. If it is you will need to spray smoething like SeaFoam in it and let it soak or figure out how to clean it up. I had a little 3 stroke MC doing that and found the muffler about 90% plugged. The back pressure will not allow gas to reach the top of the cylinder.

 

[rickdb1boat]

Re: Help! 2003 Mercury 5hp

Try spraying a little pre-mix in the carb throat while running. If it continues to run, the carb is still clogged. Did you blow out the carb passages(Jets, Ect) with compressed air? Important to do so...

 

[bryanredfish]

Re: Help! 2003 Mercury 5hp

This may sound like a dumb question, but is the vent open on your fuel tank? It sounds like a fuel-related issue. Try a different fuel tank.

 

[chunkachange]

Re: Help! 2003 Mercury 5hp

Bryan, Im using the internal tank, clean with fresh gas mix. Gas gets to the bowl just fine, it just wont go from there into the motor without choking it. Any ideas? Thanks, Chunk

 

[chunkachange]

Re: Help! 2003 Mercury 5hp

I sprayed pre-mix into the carb throat and it will run as long as I spray every few seconds. When I quit spraying the fuel mix, it runs about 5 or 6 seconds and quits. It is a 2003 model with hardly any run time. I have taken the carb apart down to main nozzle, main jet, low speed jet, needle valve, float, float hinge, mixing chamber cover, rubber "packing" seal, and plug seal. I have sprayed with carb cleaner and checked every tiny hole in every jet, valve and nozzle. All is clear and like new. Yet the only way the motor will run is if I choke it, pull the starter a couple of time, shove in the choke, and it will run for about 5 or 6 seconds and quit. <br />Anybody have ANY suggestions that I could try on my own before hauling it to the repair shop? Thanks, Chunk

 

[chunkachange]

Re: Help! 2003 Mercury 5hp

I double checked everything in the carb, the float is to specs, 1/2 inch, all jets and nozzles are clear. I am still choking the motor, it starts....I shove in the choke and turn the throttle handle...the motor responds to the throttle for 5 or 6 seconds and then dies flat. Any suggestions appreciated. Chunk

 

[Dman]

Re: Help! 2003 Mercury 5hp

Where are your idle screws set at? You are getting too much air in there for it to run. Try turning your idle screws all the way in. Start there and see if it will run. Just another suggestion. <br /><br />D

 

[chunkachange]

Re: Help! 2003 Mercury 5hp

Dman, there is only one air screw, and it makes no difference screwed all the way in, all the way out, or 1 1/2 turns out, as specified by the book. Chunk

 

[bryanredfish]

Re: Help! 2003 Mercury 5hp

Did you resolve the issue? Just curious.

 

[chunkachange]

Re: Help! 2003 Mercury 5hp

Bryan, I have tried all to no avail. I am waiting for the flooding around here to clear up and then take it to a marine repair shop. Chunk

 

[ehenry]

Re: Help! 2003 Mercury 5hp

Have you checked the fuel pump? Are you sure its pumping fuel to the carb? It may be as simple as rebuilding the pump.

 

[chunkachange]

Re: Help! 2003 Mercury 5hp

Hey efhunry, I rebuilt the carb, cleaned everything like new. Gas gets to the bowl just fine, it just does not go into the engine unless I choke it. Chunk

 

[ehenry]

Re: Help! 2003 Mercury 5hp

chunk, i'm really not too familiar with your engine. I did see that you are running on an internal tank my question is....is the fuel from the tank gravity flow from the tank to the carb or does it go through a fuel pump. Every outboard I've run had a fuel pump that worked off vacume from the engine. Ocasionally the diaphram in these pumps go out and need to be replaced. All my engines had external tanks too. Just my experience trying to help my friend.

 

[chunkachange]

Re: Help! 2003 Mercury 5hp

Hey efhenry, I appreciate any help I can get! Thanks for responding. The motor is almost new, carb has a fuel pump attached to the side of it. Fuel flows by gravity to the pump and it pumps it ok into the bowl...the bowl fills up with a couple of pulls on the starter rope. I can choke it and it runs for about 5 or 6 seconds after I shove the choke back in. It responds to the throttle during that time also, but promptly dies after those first few seconds, sounding like it runs out of gas. I can "play" with the choke and keep it running, smoking like crazy, but the instant I stop choking it and shoving the choke back in, it dies after about 5 or 6 seconds. Any ideas? Thanks, Chunk

 

[ehenry]

Re: Help! 2003 Mercury 5hp

Does does it have a primer bulb or button? If so, try depressing it when the engine starts to die. If the engine picks back up and starts to run, in my experience, thats an indication of a fuel pump problem.