Curious starting issue

I have a Honda 2002 8HP for my sailboat. I just bought the boat in July, and I know I need a new battery. I've been able to get the motor started manually (it may take 20 pulls, but it starts). After that, it readily starts up on the first pull, presumably because it is warmed up. This past weekend, however, I had the shore power cord in; although the battery wasn't charged enough (or wouldn't hold a charge enough) to start the motor, it did try to turn the engine over. Anyway, I started the engine on the first pull when the shore power cord was plugged in. We went sailing for a couple hours. On the way back in, when I tried to start the motor manually, I couldn't do it for about 20 tries. It finally started. But shouldn't it have been "warmed up" from running earlier? Or was the manual start while I was on shore power/weak battery different from a "pure" manual start? I hope this question makes sense; outboards aren't my strong suit... Thanks very much.

I think the shore power was coincidental.

It sounds like the enrichment circuit, used for starting, is not working correctly.

Since you said that it runs and idles ok, then we are left with....starting.

Part #22 http://www.boats.net/parts/search/Honda/Outboard Engine/2002/BFP8D2 XHSA/CARBURETOR/parts.html is called a bystarter valve. When the engine is cold, the valve is open an allows extra fuel and air into the engine. There is a long tube (that the picture does not show) that goes down into part of the fuel bowl. The passage is very small and it any of it gets clogged, the motor will be hard to start.

The right way to fix it is to remove the carburetor, disassemble and clean it. However, you might get lucky....try this...

Drain the carburetor bowl. Remove the part #22 by starter (held on with one phillips head screw.) Get some brakekleen with a straw on the can and stick the straw down into the small hole that the needle of the valve goes into. Give it several shots. Keep the drain of the carb bowl open to let any of the fluid and hopefully debris drain out.

If you have a can of compressed air (that you use to clean your computer), shoot some of that through the open to blow out anything left. Flush and blow a few times.

Put the valve back in (be sure that the valve goes into the small hole...and be gentle).

Flush some fuel through the carburetor with your fuel bulb and let drain out. Again to flush any debris. Then tighten the drain screw.

Now it is time to try to start the engine.

1. Make sure you have it in the water or a pair of earmuffs on it (watch the earmuffs so they do not come off).
2. Squeeze the fuel bulb until it is hard.
3. Do not advance or move the throttle from the idle position.
4. No try to start.

If you advance or move the throttle, you can easily flood the motor.

The motor should start with a high idle and the idle should slowly settle down to normal idle speed as the bystarter valve closes off the extra fuel.

If that does not work....check one other thing....the accelerator pump.

On the side of the carburetor, when you advance the throttle, there is a little plastic lever that pushes down a small metal rod into the base of the carburetor. It has a little rubber bellows (looks like an accordion) around it. The bottom part of the bellows is about 1/4" in diameter. With the throttle in the idle position, take your finger and push that rod down. It should go down and spring back up when you remove your finger. If it is stuck and does not move, it indicates that the accelerator pump is stuck due to water in fuel or old fuel and the carburetor will need to be cleaned. Depending on why it was stuck, you may need to replace the bowl and the piston (inside the bowl - that you can not see).

If the bystarter valve cleaning trick does not work but the accelerator pump is free, there is another possible workaround to get the motor started until you can properly clean or replace the carburetor.

You can squeeze the fuel bulb and twist the throttle back and forth two or three times. If it is really working, it shoots fuel into the intake manifold. Try starting the engine, it should at least hit. I can not say for sure that it will keep running, but it might be worth a try, at least for a temporary measure.

I said earlier, not to move the throttle back and forth before you start the motor.... If all is working properly, it will add fuel to the enriched starting mixture...flooding the motor. If the starting circuit is not working, there should not be a large danger of flooding.

This is not meant to make you an expert on the carburetor but might at least get you going for a while.

There is an excellent step by step written by Jimmy (aka jgmo) for either an 8, 9.9, 15, or 20 HP. I can not remember which. They all have the same circuits and are cleaned the same way. So, if you need to get more into it, do a search on the forum for that.

Mike

ps Whoops....almost forgot....this motor is always hard to start if the oil is too high. Make sure the oil is a little below the full mark with the motor vertical.

Hi,
This is the Jimmy Mike mentioned...I am here watching to see how you make out. Give us a holler if you have any questions.
I hope Mike's trick(s) work for you.
Good luck.