Yamaha 3HP won't run

[Larry1]

I have a 1994 3 HP yamaha. It was running fine, and then I went to drain the fuel tank because I was going to let her sit for a long time. Turns out I did not let it sit more than a week before I wanted to use it again, so I filled it with fresh fuel mix, ang could not get it started for the life of me. Pulled the thing many, many times. I sprayed some starting fluid in the intake and it started right up, but died within a few seconds. Suspected a few issue, but fuel is definately getting to carb (disconnect fuel line and it spouts out). Do these things have a fule pump that can go bad? Any other ideas of what is wrong?

 

[Yamajoe]

Re: Yamaha 3HP won't run

check for spark, is the lanyard connected, check the white wire from stop switch to cdi for shorts, clean your spark plug; pump the primer until firm, switch the choke on, couple of pulls, if no start, and you have good spark, start from the tank, is the air vent on, check the filiter gauzing in the tank, check the connectors for firm fitting, no leaks, use only pre-mixed fuel to spray into carb. If this does not work, you may need to service the carb.

 

[Larry1]

Re: Yamaha 3HP won't run

check for spark

Sorry, since I am a newbie to outboards (I have done extensive work on inboard gas engines) please forgive my ignorance, but if it starts and runs fine for 4-5 seconds after spraying fuel into the carb intake, wouldn't this indicate there has to be spark?

 

[Yamajoe]

Re: Yamaha 3HP won't run

Yes it does, take the plug out and give it a clean and check the gap; then proceed to checking the fuel system; after sitting for a period (hr or 2), what happens when you choke the motor, does it try to start? or does it just starts when you spray fuel into the carbs? if the answer is yes to to both ?, then you have a stuck float valve jet or blockages in your jets; remove carbs and clean using fuel and air. The reason you need to discount there are no shorts on the white wire from lanyard to cdi, is shorts will give your no or intermitant spark, hence it starts for a few turns and cuts out as the motor vibrates.

 

[Larry1]

Re: Yamaha 3HP won't run

OK, got you. Thanks for the help!