key won't start motor

[glenntav]

`hi all i'm new to the site. been asking a question on other sites and getting the run around maybe you can help. i have a 2004 johnson 40 h.p 2 stroke o/b.....bought it used last yr, runs good but never able to just use the key(choke) to start the motor all ways have to do full advanced trottle to start.

brought it to the mech and he said it was the choke sencor(changed it) and still cant start it with the key every one seem to think the only way to start this motor is full advance throttle....well useing the key also. i have a key and just want to start it like i'm starting a car, got fuel,spark ,air it runs good when it's out there....just confused.

[Rebel Sympathy]

I am assuming you are using the fuel line primer bulb correctly in your starting process. There is no need to crank up your motor at wide open throttle. In fact, it can be harmful to your engine and your net worth. Please read the following carefully:

Pushing in the key and holding it in is the correct way to start an older motor with a choke.

The newer motors, like your 2004, do not have a choke. They have a primer system which shoots a small charge of fuel into the intake behind each carb. On 30hp and smaller tiller steer motors the primer is manually activated; on remote and larger motors the primer is activated by a solenoid, which in turn, is activated by pushing the key inward. When you push the key in and hold it in as you are cranking (improper for a primer equipped motor) the primer is only giving you only one shot of fuel. A cold motor will need more than that.

So, as you are cranking over the motor, you need to repeatedly bump the key in (and then let it out after each bump). That way, you can get additional shots of fuel into the intake - (one shot each time you bump the key inward) as the motor is cranking over. Immediately for the first few seconds after the motor cold starts you may have to give the key another inward bump or two to keep the motor running until it gets a little warmpth into it. Please note I stated ".....as the motor is cranking over." It will do no good to keep bumping the key inward if the motor is not cranking over and recharging the primer with new fuel. The motor must be cranking over to recharge the primer.

This is the normal method of properly cold cranking these primer equipped motors. I'll wager there is nothing wrong with your motor. I have a 1998 115 and if I did not start it by using the "bump key" method several times, I would never get it started when cold. It is actually addressed in my owner's manual, but the manual does not do a very good job of explaining how important it is, nor emphesize how to actually get the full benefit out of the primer system.

[glenntav]

thanks for the reply i'll try it.....it does make a little more sense now.

[glenntav]

I tryed that method....bumping the key while trying to start but nothing had to go to full throttle advance

[Rebel Sympathy]

Well, since it runs good, then it must have good spark and compresion and the carburetors themselves must be fine. I'd say it is either flooding or starving during cold start. You've got to figure out which.......

If you are using the primer bulb on the hose correctly and priming the engine with multiple shots with the key, then having to go to WOT to get it to start might well mean it is flooding. Try cranking it up cold with no key priming at all. You still will first need to sqeeze the primer bulb until you begin to feel firmness, as is true with any cold start. You may have to give it just a little throttle. Let me know what you find out.

[Rebel Sympathy]

One more thing......

Make certain you have the correct spark plugs in your motor. Champion QL78YC.

[glenntav]

oh i do alright .....the mech. put in NGK'S last time ....took them out and put in champions at .030 gap. he had those ngk's at .050 for some reason....yea it ran ok but not the right plug.

[Rebel Sympathy]

We used to joke at OMC outboard school:

NGK = No Good Kind

AC = Almost Champion

Motorcraft = MotorCrash

Autolite = Ought to Light

[glenntav]

i think i found the key starting method.......like i said i was turning the key plus pushing the choke and every time....no start. pretty much i think flooding the system. so today i got the muffs out tryed to figure it out. so i advanced throttle to start and let it idiol ... then shut it off. now i then started it key and choke many time and nothing. now i advanced throttle to start again and let it idiol ....shut it down and just turned the key and what do you know she started time after time.

[Rebel Sympathy]

That is good news. Sometimes it seems each motor has its own personality. Once we learn them, they become a reliable friend. Glad you found what your motor likes.

I should have picked up on the fact you were flooding the motor because wide open throttle is the way you clear a flooded engine - be it outboard, weed-trimmer or automobile.

[glenntav]

when brought to the mech. and told him that I couldn't start it with the key he suggested it was the choke sensor and he changed it. I have a feeling the old sensor was good cuz I never tried to start it the right way .....well we'll never know now. probably paid $250 for nothing, lesson learned I guess. at least I have a new part if you think of it that way .