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honda 15hp wont idle

R

rodey

Contributing Member
engine is a 2007 bf 15
manual start
pull choke and starts rite up
soon as i push choke in the engine will die
now if i keep choke knob out just a small amout it will idle away no problem
carb has been soaked and clean twice

it has had a new enricher [choke] cable installed
does this have to be adjusted
ant help would be appreciated
 
You still have a fuel restriction issue, Check all connections from fuel tank to carbs for security and possible air leaks. Try pumping primer bulb to keep engine running
 
Hi,

Sorry you're having problems with your Honda.

When you replaced the choke cable, did you also replace the "valve set" (item 12 in the link below)? The reason I ask is that the plastic threads on it that screw into the carb body get a bit chewed up because they are delicate and engine vibrations "work" on them over time. As a matter of fact, it's fairly easy to ruin a brand new one if you get a little careless during initial installation. If those threads are damaged in any way. the choke won't work properly and the valve set will be loose in the carb body.

http://www.boats.net/parts/search/H...er/BF15DK0 LHA/CARBURETOR (MANUAL)/parts.html

Also, another item that can cause starting and running issues with these particular models is the "fuel chamber" (item 2 in the link below). They can act as a water separator and start filling with condensate. They need to be removed every so often and emptied of all liquid. It's easy to do. Just disconnect the fuel lines going to it and then slide the holder (item 3) up and off of the engine oil dipstick tube. Do this with a great degree of care so as not to damage the dipstick tube. A little cooking oil works well to help it slide up and off the tube. Shake all the liquid from the chamber and put it back and hook up the fuel lines. That's it.

http://www.boats.net/parts/search/H...07 and Later/BF15DK0 LHA/FUEL PUMP/parts.html

I hope one or both of these ideas help you get her going right again.

Good luck.
 
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When those things don't work, then it is time to check the main jet and the jet set #22 and #5 in Jimmy's link.

The starting circuit is probably ok...which takes the fuel from the bowl and combines it with air from a special intake and feeds it through the carburetor to the motor. Once you push the choke in, it closes that feed down and if the engine stops, it tells me that the normal idle circuit is plugged up. Most likely at the main jet or in the skinny tube (jet set).

Mike
 
thanks lads for all suggestions,
at the moment ive the carb back off and stripped,
im leaving it soaking for a few days to see if it clears anything up,
ill post back up here as soon as i get it back together and let u know the outcome,
thanks
 
Well, if you have the carb off DO NOT ignore hondadude's suggestions about the jet set tube. Sometimes the ONLY way to get one cleaned out enough to get it to work right again is to throw it in the trash and install a new one. They also tend to crack vertically so look carefully for that. You should use a new oring at the top of that tube and take great care not to damage it upon install. That's how critical that tube's integrity is to the operation of these little carburetors.

Good luck.
 
rodey said:
thanks lads for all suggestions,
at the moment ive the carb back off and stripped,
im leaving it soaking for a few days to see if it clears anything up,
ill post back up here as soon as i get it back together and let u know the outcome,
thanks
Click to expand...

Good luck rodey - two notes of caution here: 1. When soaking - take care to not damage the rubber parts (orings, seats, gaskets) by the "soaking agent". And 2 - use compressed air to insure all the orifices and passages in the carb are flowing freely!
 
When you're cleaning, pay especial attention to the (3?) TINY ports that are uncovered AS the throttle is slightly opened. It is also normal (at least for me!) to have to repeat the cleaning process several times before the crucial passage is fully opened.

I have also seen (on this forum) that Honda carbs shouldn't be dipped since it would remove an anti-corrosion coating. JGMO? Hondadude?
 
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mf70 makes good points. The orifices at the top of the carb throat near the throttle plate SHOULD be spray flushed with brake clean (in some locales) or low voc cleaners such as are sold in California.

The HARSH but very EFFECTIVE carburetor "dips" such as the Berryman's product we used for decades should NOT be used to clean these carburetors due to their ability to destroy the plastic components as well as the coatings.

hondadude also warns against spray compounds labled "carburetor cleaner" because they can damage the coatings.

The cleaning method recommended in the Honda Marine Carburetion Manual is ultrasonic cleaning.

So, you do need to be cautious about about how you clean a Honda carb.
 
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agian lads thanks for all the info and advice,
well iv been spraying the carb for the last few days every eve with a cleaner i use that usually gets good resultd.
today i decided to blow the whole thing out with compressed air , rebuilt and back on,
put fresh fuel in and gave her choke and 2 pulls and it started,
only ran for a few seconds then pooped threw the intake and died,
i tried a 8hp carb and the engine ran fine so defo carb trouble,
must be a blockage interanlly somewere
 
Try this:

With the float chamber off, make sure that the two little "tunnels" in the bottom of the chamber will pass a very small diameter wire through them. I use a piece of copper wire extracted from a section of multi-strand automotive electrical wire. Use the spray straw with your pressurized can of cleaner to blast them out and the wire to rod them and check that they're clear.

After doing that, take the accelerator pump piston out and locate the passage that feeds the accelerator spray tube that juts out into the air stream in the front of the carb throat. It is a skinny brass tube.

After locating and clearing that passage in the float chamber, use it as a reference to locate it's mating passage in the carb body that feeds that little brass tube. When you have that passage identified, open the throttle plate all the way and prop it open. I use a pocket screw driver to accomplish this.

Once throttle plate is propped completely open, use the cleaner straw and fire a blast through the passage that feeds the little brass tube. Be careful and don't spray yourself. IF THE SPRAY STREAM FROM A PRESSURIZED CAN OF CLEANER DOESN’T SHOOT OUT OF THE BRASS TUBE AND OUT THE BACK OF THE CARB AT LEAST 6 TO 8 FEET.....AGAIN.....6 TO 8 FEET.....
the accelerator tube and nozzle are clogged.

If the tube ia clogged, look through the back end of the throttle bore and locate the spray nozzle on the end of the brass tube. Insert the spray straw into the bore, past the propped open throttle plate and hold it up against the spray nozzle. Give her a good blast. Then, insert the straw back into the feeder passage and give it a shot.

You MUST get the spray stream to shoot out the back of the carb 6 TO 8 FEET or the engine will not run properly. Continue with spraying in the nozzle and then the passage until you get a good soaker stream out the back of the carb. Back and forth, back and forth until you achieve that stream.

What I've given you above are the two most problematic areas of getting these Honda carbs COMPLETELY CLEAN.

Good luck.
 
hi lads
well looks like i may keep a look out for a carb
had a guy put mine threw a ultrasonic cleaner and it still wont idle
thanks for all the help
will update whenever i get it sorted
cheers
 
rodey said:
hi lads
well looks like i may keep a look out for a carb
had a guy put mine threw a ultrasonic cleaner and it still wont idle
thanks for all the help
will update whenever i get it sorted
cheers
Click to expand...

Well, everyone has to draw their own line as to effort/results. For those of us that own just the one motor, our training to produciton ratio isn't very efficient. If you just want to go fishing, buying a new carb doesn't actually cost an outrageous amount.

OTOH, it can take several tries before you find ALL the tiny passages that need to get cleaned. It took me three cycles.
 
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