honda bf8ah won't start

hello folks, i have posted here sometime back in regards to my motor not starting & the info that you gave me helped a bunch & the motor ran fine but i now have a new starting problem that i could use some input on. the motor sat for a month with the gas ran out of it, when i tried to start it the other day with fresh gas it would not start. i was getting gas to the carb but nothing to the plugs,dry as a bone, so i tried taking out the #10 screw plug & blew it out with compressed air, put it back in & it started right up on the 2nd pull with full choke. it idles & throttles up like it was brand new. shut it off & let it set for 3 hours & it won't start again until i take the #10 plug screw out & blow air in it. this i do not understand.could someone please explain what is happening ? it seems to me if the passage was blocked & the air cleared it then that would be problem solved.also is there a hole that i can't see inside this #10 plug/screw & if not, what is it for? this one is zinc & is it a special part or could i get one at a hardware? i would like to replace it with a steel one that i can hold onto with a parts magnet because i may have to do this on the ocean & it is hard to hold onto, thanks, sorry this was so long !

Hi,
Sorry you're having trouble.
This is just a guess but I think that when you blow into the passage you are simply displacing whatever debris that's in there and pushing it over into a "corner" of where the cross drilled passages intersect each other. It probably stays "pinned" in that spot by the flow of fuel while you're running the engine and then sort of "rides the ebb tide" of fuel back into the passage when the flow stops.

I believe that you would be well served to just remove the carb and flush it out properly. A bit of work but then be done with it.

As far as holding the screw is concerned, if you can find a steel replacement that fits PROPERLY and doesn’t damage the threads then I see no harm in using it.

Good luck.

Hey, thanks a bunch for the info & I will take the carb off & flush it out & see what happens. I'll post the results just in case someone else has a similar problem.
thanks again,
Mick

Your best bet is to remove the float chamber and blow the air vents out as well as through the screw hole.

The vents are very small holes that you can only see by looking up in the body cavity with the bowl off. Once you locate them you can associate them with the vent holes on the outside top of the body.

Also, direct some spray into the tiny passages at the top of the carb throat. They are on the throttle plate end as opposed to the choke plate end. Open the throttle plate all the way to access all the little drillings.

Also direct air through any passages that you see on the very end of the body around the carb throat on the choke end. These passages will be larger than most of the others
Around 1/4" or so in size.

Lastly, remove the emulsion tube and jet and then blow/flush the passage they connect to in the center top of the body.

The more you stare at and examine the carb body, the more you will see just how many little passages there are to clean.

Good luck.

Thanks for the info ! I will pull the carb off & clean it real good. Should the carb be soaked in a solution or should i just spray it with carb cleaner ? If it needs to be soaked,what should i use ? looks like the # 10 plug is going to have to be ordered.couldn't find anything that would fit at any hardware stores here.

I don't recommend soaking since most carb soak cleaners are too harsh for many of these little carbs. If you're in California you can use carb spray but hondadude warns that many of the carb sprays are too harsh elsewhere so he recommends brake clean as an alternative.

Hopefully after you wash it out you won't be needing to remove the screw to get going any more.

Good luck

As already stated and proven on this site.-----------No offense------It sometimes takes folks 3 or 4 attempts at getting these carburetors clean.---------When you remove plug # 10 have a good look in the carburetor.-------You should see a tiny hole in there that needs cleaning.------I used to keep a single strand from electrical wire to get in that hole.

Honestly you need to remove the carb, dismantle it, clean it, blow it out. While you are there inspect all fuel lines and replace any inline fuel filter if you have one. If you don't I suggest slicing one in.

If you have any crystallization in a place you can't really get to in order to clean it properly. Save yourself the headache and just buy a new carb. www.boats.net for a replacement.

As jgmo has stated and Hondadude will tell you the honda carb manual will be an asset,there are alot of intricacies to them