Problems starting engine......HELP w/ Diagnosis??

[SeaPA]

I just recently had my carbs rebuilt (I have a 2 stroke 115 Yamaha) and the engine runs great now while idiling or at low speeds.

However, I have a terrible time getting the engine started now. I feel like I have to crank, crank & crank some more to get it started. I prime the buld until its hard and I push the key in & out several times before starting.

I feel like the engine is smoking a lot more now then before (maybe the fuel/oil ratio is to rich??).

I have started adding 2 cans of Seafoam everytime I fill my gas tank up (60 gals) in order to keep the carbs clean, a tthe recommendation of my mechanic.

Any help would be great!!!

 

[Megabyte]

I don't have any experience with that particular motor, but I did own a 2000 model year carb'ed Johnson Ocean Pro with the "push to choke" priming solonoid...

When you push to prime, can you hear the priming solonoid clicking, indicating that it's squirting fuel?
I'm thinking by what you describe that your primer isn't working properly.

What year is your motor?

 

[DaleH]

First off, I'm a #1 fan of the Seafoam & Deep Creep decarb/cleaner products but ... lose your mechanic ... there's NO WAY your carb'd OB needs that much of any solvent on a routine basis IMHO.

Now that said, yes ... if I were running a newer motor with an O2 sensor, then I would be adding something like Ring Free as a preventative to keep the sensor clean. FWIW I've never ever had to rebuild a carb my whole life on any carb'd OB I or that any of my brothers have ever owned, and that has to be > 30 OB motors over the last 30 years.

Starting Sequence:
As Kevin says, that motor uses a PRIMING system, not a CHOKE system and the difference between the two is key. Also as he said, make sure the primer solenoid is working, without cranking the motor you should hear it "click" when you push in on the key.

Whereas a choke makes the mixture run "rich" (more gas relative to the air volume), the priming system works by dumping raw fuel from fuel/oil mix pump directly into the carb throats, by-passing the bowls which are fed via the fuel manifold.

Please try this as your routine starting sequence :

• 1) Hold OB-end of fuel line higher than the primer bulb and pump it until firm
  
  2) Turn key ON, but do not crank, and push in on the key and HOLD for a slow count of 6-8
  
  3) Release key from being pushed in and turn to crank
  
  4) She should start right up

You should NOT have to do that but once a day. When warm she should start right up, though you should check the bulb. Bulbs do go bad, so if it doesn't stay firm, replace it with the one made by OMC/Bomb (the BEST of the primer bulbs out there, even MErc use their bulbs), or the Yam version, but DO NOT use one made by Tempo (junk~!).

The first couple times you try the sequence above ... re-check the primer bulb for firmness before you crank to start.

 

[SeaPA]

The engine is a 2000 model Yamaha 2 Stroke 115 HP.

It does look like there is a choke knob on the front of the engine (towards the transom) but I have never used that to start the engine.

I will definitely try Dale's starting sequence and see how it works.

I will also listen carefully when I push the key in to see if I hear the engine squirting fuel into the carbs.

I did think that was a little odd that the mechanic told me to add two cans of Seafoam to every full tank of gas. Seemed a little excessive to me.

 

[Megabyte]

Whatever type of system you have (choke or primer), there will come a day when you will flood her.
As Dale said... once the motor is warm, you should not have to prime her again that day. If you do, you could flood her.

Don't ask me how I know this...

1. To overcome a flooded outboard, release the binicle by pushing the button at the center of the lever to free it.
This will ensure that she isn't 'in gear'.

2. Push the throttle to full open (WOT).

3. Keeping one hand on the throttle, crank the motor by turning the key with the other hand...
Be ready because when she starts, she will tach up quickly!

4. Once she catches and starts, ease back on the throttle to a reasonable point until the extra fuel is burned, then throttle back to idle.

The procedure is the same one we all used back in the days of carbs on our cars, and before the advent of computerized ignition.
Foot to the floor... crank, and pick your foot up when she fires. :wink:

 

[Porkchunker]

I've had a lot of experience with carbed 2-strokes. For the most part, the solenoid you speak of pulls the choke plate closed across the carb opening, causing the vacuum behind the choke plate to pull extra fuel into the venturi. Pushing the key and releasing it then trying to start does nothing for you.

To choke the engine, you must push the key in, and hold it in while turning the key to crank the motor. A 2-second push while cranking should suffice. Any longer, you risk flooding the engine with excess fuel.

Once the motor starts let it run until it sounds like it is starting to die, then push (don't turn) the key for 1/4 to 1/2 second and let it go. The motor should pick up and run for a while more. You may have to repeat this 1/4 to 1/2 second push (choke) a couple of times before she runs alone without choke.

This is the way all of my Johnson/Evinrude engines and a few Yamaha motors I've encountered have operated. Not sure if this is true of the more modern HPDI engines.

Check your operator's manual to validate how to choke the engine. If you don't have one, you can probably still download them from the manufacturer's site.

 

[DaleH]

Pushing the key and releasing it then trying to start does nothing for you.

On an OB with a true choke function - yes, but not on an OB with a primer system. Just to clarify so Seapa follows the correct advice specific to his OB type ...

 

[SeaPA]

Dale,
I tried your starting sequence last night when I got home from work and I still had to really crank on her to get her started. Once started, I cut it off and restarted it several times and it worked just fine.

When I push the key in, I hear a clicking noise that happens immediately (i.e. I only hear the noise for a split second, it doesn't continue to make a noise as I hold the key in).

Does this sound like its working properly or is it supposed to continually make noise (i.e. like its pumping) while I hold the key in??

 

[DaleH]

I still don't know whether that motor uses a traditional choke system or a primer system. But either way, you should ony hear the click once when the solenoid moves.

Have you checked the gap on your plugs and are you using the right sparkplug? I find that hardstarting on a motor that wants to run is sometimes caused by the simple stuff and a gap that's off even 0.005" can cause issues. FWIW on my V6 motor, I regap the plugs every 50 hours and replace them @ 100 hours. But I get mine for $2 each from my local auto parts store ... not the $6 each the boat stores charge for the same plug.