15 hp difficult cold start.

Hello, I have a 2003 BF 15D tiller, auto choke s/n 1003387.

This motor used to cold start and run like a champ.
Motor sat for a year without use and developed the cold start issue.
With fresh fuel I set the tiller to start than press the fuel bulb till hard and have to press the start button 15/20 time before it will stay running.
Once its running it runs and starts perfectly for the rest of the day.
Not sure why the difficult cold start than no issue for the rest of the day.
Do you think it could be the auto choke? Is there a link or description of how to test.
Or does this sound like a dirty carb issue. If so is there a description or link for that
Motor is still in storage till the snow melts, but trying to get some ideas on what to do when i get it out.

Thanks

I would definitely check out the choke in a situation like this. I think this one uses a solenoid to operate the choke? If so, have you pulled the hood and verified that the linkage is moving when you push the key in? I don't have experience with that system so, hopefully, someone that does will chime in. It does sound like a choke issue regardless.

Good luck.

P.S. I looked at picture of choke solenoid on boats.net and if you're hearing it click loudly when you push in the key, then taking off the hood and checking the linkage IS the thing to do. There are several places it could get loose and separate or go out of adjustment.

https://www.boats.net/catalog/honda...hp/bf15a2-sas-2002/choke-solenoid-bracket-kit

This motor has a thermal enrichment device, I would strip and clean carb thoroughly and make sure the accelerator pump is working. These enrichment circuits on these motors can be troublesome but with accelerator pump working, three slow twists of the throttle before cranking will result in instant start up every time.

Ok, I don't know why I thought I read 2002 but getting old ain't for sissies!

Yes, I stand corrected, it should have a thermal enrichment valve on the carburetor.

I would still recommend checking it's operation before tearing the carb down. It's easily removed and easily tested. The TE valve should be in the enrich position when the engine is cold and when the valve is cold. As the engine runs, the valve receives chargeing volts and typically will extend over a 1 to 1-1/2 minute timeline.

It is a pintle valve that sits atop the carb and is normally in the retracted (enrich) position.
It is held in place with one machine screw and a c-shaped hold down. You need to unplug the single wire electrical connector before attempting to raise it straight up after removing the screw and clamp.

To test, use jumper wires to connect the plug to the positive post of a 12volt battery and ground the body of the valve to the negative post.

In approximately 1 minute the pintle should begin to extend and be about 3/8" longer in 30 seconds.

These valves rarely fail and, when they do, they usually don't move at all.

In this case though it could be that yours has had the pintle stick in the extended position and will not retract to allow for proper enrichment for cold starting.

If you find that this is the case, you might be able to "unstick" the pintle and have it work again. But, I would seriously consider replacing it and it's oring anyway. They are not terribly expensive.

If you find that the valve works as it should, then a carb cleaning is definitely the solution to your problem.

Not trying to argue with iang's advice but you did say that the engine ran fine otherwise and you wanted to know how the TE valve works and is tested.

So, there you go.

Good luck.

Thanks for the very informative reply's that is exactly what i was looking for.

Please let us know what you find. While people do clean and rebuild these little carbs....it's not as simple as it may seem. Most "first timers" end up taking the carb off several times because they are just unaware of the way they work. One thing I always recommend to someone that hasn't done carb work before is to purchase the HONDA MARINE CARBURETION MANUAL. The manual makes it possible for a DIY'er to get it right the first time. Last I checked it was about $35 on Amazon. Well worth the money even for experienced carb rebuilders.

Good luck.