Honda BF-100 air intake issue
 

I just bought a used Honda BF-100 9.9 horsepower outboard that's about
12 years old. It runs fine and starts on the first pull but...

When i put the top cover onto the engine, it runs out of air and starts
to shut down. If I pull the lid up a little and let some air inside,
it will keep running. If I leave the lid on, it runs out of air and
stops within a minute.

I can only see one air opening in the top lid and that is where the
handle fitting comes in. I drilled out some extra holes next to the
existing holes in that handle area but the problem still happens.

Is there another source for fresh air to the motor besides the small
slit in the upper handle area?? I can't find a hose or anything to
indicate an air intake anywhere on the motor.

Any suggestions appreciated.

-jw

"Wallis" wrote in message oups.com...
I just bought a used Honda BF-100 9.9 horsepower outboard that's about
12 years old. It runs fine and starts on the first pull but...

When i put the top cover onto the engine, it runs out of air and starts
to shut down. If I pull the lid up a little and let some air inside,
it will keep running. If I leave the lid on, it runs out of air and
stops within a minute.

I can only see one air opening in the top lid and that is where the
handle fitting comes in. I drilled out some extra holes next to the
existing holes in that handle area but the problem still happens.

Is there another source for fresh air to the motor besides the small
slit in the upper handle area?? I can't find a hose or anything to
indicate an air intake anywhere on the motor.

Any suggestions appreciated.

-jw


Clean the mainjet in the carb. It's not running out of air, it's running
out of fuel. Serious.

CN

Clean the mainjet in the carb. It's not running out of air, it's
running
out of fuel. Serious.

CN
Thanks for the quick response.

Okay, I'll try that - but- it runs like a champ, even under full load,
with the top removed. That's why I think it's an air issue, when I put
the top down tight it dies...if it were the fuel, wouldn't it die even
with the top lid off?

JW

"Wallis" wrote in message oups.com...


Clean the mainjet in the carb. It's not running out of air, it's
running
out of fuel. Serious.

CN
Thanks for the quick response.

Okay, I'll try that - but- it runs like a champ, even under full load,
with the top removed. That's why I think it's an air issue, when I put
the top down tight it dies...if it were the fuel, wouldn't it die even
with the top lid off?

JW


I suggested it because I have a newer 9.9 Honda and I had a similar problem.
Mine has that throttle safety interlock thing, though, that doesn't let it rev up
much in neutral but it would idle just fine and up a ways with the lid off but
not with it on. It was running too lean on fuel/air mix because the mainjet was mostly
clogged up with lacquer from stale gas and taking the lid off gave it more air
and made it worse.

Since you drilled extra air holes and it didn't do any good, I would assume it's
not that . . .

CN

"Capt. Neal®" wrote in message ...

"Wallis" wrote in message oups.com...


Clean the mainjet in the carb. It's not running out of air, it's
running
out of fuel. Serious.

CN
Thanks for the quick response.

Okay, I'll try that - but- it runs like a champ, even under full load,
with the top removed. That's why I think it's an air issue, when I put
the top down tight it dies...if it were the fuel, wouldn't it die even
with the top lid off?

JW


I suggested it because I have a newer 9.9 Honda and I had a similar problem.
Mine has that throttle safety interlock thing, though, that doesn't let it rev up
much in neutral but it would idle just fine and up a ways with the lid off but
not with it on. It was running too lean on fuel/air mix because the mainjet was mostly
clogged up with lacquer from stale gas and taking the lid off gave it more air
and made it worse.


Made it better - not worse. Duh!

CN

On 18 Apr 2005 16:14:38 -0700, "Wallis" wrote:

I just bought a used Honda BF-100 9.9 horsepower outboard that's about
12 years old. It runs fine and starts on the first pull but...

I had four of these mounted on a 12' Jon boat when I was 5. I was the
envy of my whole kindergarden class, and on my way to boat greatness.