BF 25A Fuel Line/Bulb Issue?

Hi,

Before I take it to shop I'd like to see what you guys think. I been given good advice here before so here goes. Last weekend I couldn't get it started at the boat ramp. It ran fine in the shade in the yard 20 minutes before. The bulb doesn't stay hard for long when in the sun so I replaced the dry rotted fuel lines with new 3/8 lines and clamps. The bulb is about 6 months old and is 1/4 or 5/16. I also replaced the gas tank when I replaced the bulb. Almost the same story today. Ran fine in the yard, got out of the wake zone and gave it gas and it slowed down, sputtered, and died. I was finally able to get it restarted and when the motor was about to die again I'd pump the bulb and it would keep running. Again, the bulb wasn't keeping pressure in the sun. I'm thinking it's a simple fuel pressure leak issue.

Questions:

1. Since I replaced smaller fuel lines with larger but didn't replace the bulb for 3/8 line is the bulb not able to to keep pressure in the bigger fuel lines?
2. Is that fact that it runs fine in the shade but after being in the sun for awhile causing expansion and leaks somewhere?
3. Bad gas in addition to the above issues?

As of now the bulb is hard and has been holding pressure in the shady spot in the yard for an hour. When I got it home I immediately ran it to flush the motor and it didn't run very well. I just ran it again and it ran better but was still hard to start. I hope I've included enough details. Thanks for your thoughts!

It is possible that due to the 3/8" hose on a 5/16" fitting, the engine may be sucking air when the engine starts trying to draw more fuel when accelerating.

I would first change the 3/8" hose to 5/16". Then it will match the fuel connector and the bulb. Also, be sure that the bulb's arrow is pointing toward the engine. Also, make sure that your tank is vented.

Lastly, drain one of your carburetors into a glass jar and check your fuel for water or other pollutants.

Mike

The shop confirmed the need to go back to 5/16 line. As far as venting the tank, I've got a 6 gal. tank from West Marine that doesn't have a vent. Should I just unscrew the cap enough for air to get in? The original Honda tank doesn't appear to have a vent either. Can you explain why venting the tank is important? Sorry to be so ignorant of what should be so simple but I've got to learn somehow. Thanks for your help Dude.

the vent for the tank is a little round knob in the middle of the gas cap...turn it counter clock wise....if the tank is not venting then there is no air to replace the gas as it us used...engines will suck the bulb flat because there is no gas feed..west marine was selling moeller tanks a few years ago and they were having trouble with the vent...so you had to crack the cap..
the way this system works is this...you pump the bulb and gas feeds into the carb(s).. when the float in the carb gets high enough it closes the valve and no more gas is fed to the carb...the bulb gets hard..if everything is as it should be with the motor not running the bulb should stay hard...once you are running the engine it will not be hard...

Good explanation.

The Honda tanks do have a little knob on the cap. Unfortunately, because of the new EPA requirements to limit venting, some tanks do not have a vent in the cap and in those cases, as special hose assembly is required like this one http://www.westmarine.com/buy/west-...t-female-w-rectangular-post-6-x-3-8--14705701

The writeup in the link explains how it is supposed to work.


Mike

4 years ago when i first run into the problem moeller would not admit they had a problem with their 6 gallon tanks...now it is mentioned several places on the web and they are supposed to have fixed the problem with a new cap...i have not called them to see if there is a free cap replacement...you are right Mike...another epa required 'fix'....

Update: Put in new 5/16 line and was able to run. Ran for 15 minutes going out without venting the tank but remembered and unscrewed the cap some. I vented the tank 20 minutes before I put in but didn't remember to leave the cap loose. I ran about 30 minutes wide open/20 minutes stop and start before shutting down for almost 2 hours. Then hard to start. I didn't replace the gas but will before I go out again. Please understand, as a guy running a 21 year old 25bfa I have to mind my expenses. Would higher octane gas make any performance difference assuming my other issue was bad gas? The owners manual calls for 89. The bulb is vertical. Regardless, the marshes were beautiful, the boat planed, and if I ate stingray it would've been a feast! Thanks for helping me to better understand.

if it calls for 89 then use 89...

did you pump the bulb before starting it for the two hours?

in many many years of boating i have never run with a bulb in a vertical position....probably nothing wrong with doing so but i run with them horizontal..maybe i just dont trust the anti siphon deal in a bulb that much...