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Need 10+ pull in warm start-Honda BF15 outboard motor

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Honda_boy

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It is 2003 Honda BFD15 carburetor manual outboard motor, I bought it two years ago. It just needs 1 pull for cold start, but it needs more than 10 pulls for warm start. If I unplug the connector from fuel tank 10 seconds before shutting down, it helps less pull for warm start sometimes, but not always. (My friend suggested me to let the motor run a bit without connecting to fuel tank, so that less flooding).

The fuel pump, fuel filter, valve adjustment have been done last year.

As the diagram in boats.net, https://www.boats.net/catalog/honda...alj-1000001-to-balj-1099999/carburetor-manual
(1)should I replace item #2: float valve pin.
(2)should I replace item #11: starter valve set
(3) In terms of operation, I feel it is a guessing game for choke. For cold start, I choke on, it starts by 1 pull easily; For warm start, I leave choke off, it starts by 10+ pull. I understand the mix ratio of air and fuel in cold/warm temperature, but in practice, when sitting on the lake, it is hard to tell the temperature is suitable for cold or warm start, which require choke on or off. To avoid flooding in warm start, I firstly leave choke off (assuming warm temperature), pull 7-8 times. if it started, then bingo....if not, then choke on, pull another 2-3 times. Am I doing correct?

Attached is the pic of the motor. Any insights will be appreciated.
 

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Hi,
I know from much experience the problem that you're having.

The "bystarter" choke on these is a pain and will not work correctly when it falls.

It is likely that you need to replace both item #11 valve set AND item #17 cable.

#11 is the cable housing and guide. When it wears inside, it allows the cable to "kink". When the cable kinks, it will no longer completely close the bystart circuit, allowing an always rich condition that only gets worse over time the more you use the "choke".

The cable and "valve set" used to be sold assembled but Honda got greedy and now, it seems, makes you assemble the the two. IT'S NOT EASY TO ASSEMBLE!
You need to be careful mating the cable and housing.
DO NOT try to replace just the housing or the cable because the other part looks "ok". It won't work and you'll likely end up with a mess and need to order parts again.
The cable and housing work together as a pair and should be replaced as a pair.

Something else to warn you about is the plastic threads of the "valve, starter", (housing). They are delicate and will strip easily if over tightened.
If the threads strip, the housing will be loose and you'll be back to ordering parts again.

Bottom line is that these ARE exceptional outboards but that bystarter "choke" is just a pain. Works great until it doesn't.

I close with the other fuel system "hassle" on these fine outboards.
The "fuel chamber". Item # 2 in the link.


That part can act as a water "trap" and will cause problems if not emptied of liquid at least once a year.

Note that there is another page (fuel pump 2) for fuel pump showing a different configuration of the chamber. I believe that is the "upgrade" that Honda came out with to solve a leaking problem with that chamber. However, I don't recall the details.
Suffice it to say that, no matter which one you have, empty it out every so often.

Good luck.
 
Thank you so much, jgmo. I will definitely replace the "bystarter" choke #11 and its cable #17. Just one more question, if it works well after replacing #11 and #17, as question (3) above, shall I still turn on the choke for the warm start, or leave it off, and let the "bystarter" do its automatic adjustment? If the cold and warm starting requires different choke, it is an still a guessing game for me.
 
Happy trying to help you sort this out.
The manual control "bystarter" that you have has no "automatic" function like the electrically controlled "auto" carb does.

Your bystarter's operation has to be manipulated almost exactly as you would a conventional "butterfly" type choke.

So, yes, starting can be a bit of a guessing game depending on the engine temperature as well as the ambient air temperature.

Theoretically, when the engine is warm, you should be able to leave the choke cable all the way in or "off" and the engine should fire right up. But it just doesn't always work like that and you may need to pull the cable out a little. But, usually, not all the way.

Every engine is different in this and will likely have it's unique "personality" in varying temperature conditions.

Probably the most useful thing I could suggest is to make small adjustments when pulling the cable out so that you don't flood the engine.

If you do accidentally flood the engine you can do what is called "clear flood" simply by pushing the cable in to "off" and then opening the throttle all the way. Several rotations of the engine in this configuration will clear the flood.
However, the engine may start when doing this and rev up to max rpm so you MUST be alert and ready to close the throttle as quickly as you can so as not to stress the engine.

The bottom line is that you need to do a bit of experimenting using the choke under different conditions and, eventually, learn what works best.

Always open to discuss with you if I'm able. But I am in a hospital bed as I write this so, if you need assistance and I don't answer right away, please know that I'm not ignoring you.

When putting that cable and housing together I always had trouble. But maybe it's just that I can be a klutz at times. You may actually find it isn't too hard at all.

Good luck.
 
Much appreciated for your thorough explanation. It really gives me a better understanding and gain more confidence on my outboard now.

I wish you a speedy recovery!🙏🙏🙏
 
Hi jgmo,

how are you today?

I removed the carb, can you help me identify those brass tubes? I can't find idle jet to clean, and those tubes circled in blue seems not removable. can you take a look at the 3 questions in the pictures whenever you are comfortable.

thank you,

Charles
 

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Never mind, I am kind of figure it out now. (1) is main jet screw (2) is connected to accelerator (3) is removable main jet . Just don't see idle jet.

Take care, Jgmo.
 
I would install a manual primer as found on many smaller Johnson / Evinrude motors.-----Likely available used and you can't beat simple when on a fishing trip.
 
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