Fuel restriction on 94 honda bf35

[fish hed]

I have been trying to get my honda 35 ready for the season but am currently having trouble with a fuel restriction i think? Motor runs ok at low rpm and after @ 1-2 min of running it seems to get starved of fuel. Rpms drop off and runs rough. When I pump the primer bulb it goes back to normal for a bit. On my last try today (After replacing entire fuel line, both female quick connects, vent cap, and water sep) primer bulb wanted to collapse at high rpm. Ive also cleaned my portable tank pick-up screens. This problem seems to be getting worse the more money I spend. Is there something with the engine itself that Im overlooking? Carbs were recently cleaned too. Thanks for any suggestions.

 

[DJ]

Re: Fuel restriction on 94 honda bf35

fish hed,<br /><br />Your collapsing of the primnewr bulb is a sure sign of a venting problem in the fuel suystem.<br /><br />I am assuming here that you are running a portable tank? What kind?<br /><br />There has to be a vent somewhere.<br /><br />AS A TEST ONLY, I would suggest running the engine with the fuel filler cap loose, to see if that makes a difference.

 

[fish hed]

Re: Fuel restriction on 94 honda bf35

DJ- yea its portable- Honda tank, came with the boat. Got a new cap for it also. Ran it today with and without the cap on. Same thing- dropped off a couple grand and ran rough. I left the throttle up a little and did the best I could with the primer and it would go back to normal so sounds like a fuel restriction to me? What about air getting in? The new female quick connects dont seem to fit as tight as the ones I replaced. But if airs getting in why is my primer collapsing at high rpms? Could it be a fuel pump problem? Thanks in advance!

 

[jim dozier]

Re: Fuel restriction on 94 honda bf35

Take a look at your fuel pump, it may be the problem. It sounds like you have eliminated the fuel systme upstream of the pump. The fact that pumping the bulb picks the engine up a bit sounds like the fuel pump. I'm not familiar with the Honda fuel pump but I'm guessing its not too complicated.

 

[fish hed]

Re: Fuel restriction on 94 honda bf35

JimD- Thanks for the advice. I had hoped that all the 10s and 20s I spent at west marine would have fixed it. I'll give it one more chance with new sparks and a new tank male connector tomorrow but after that I guess the fuel pump is the next logical step. Thanks again for easing my frustration.

 

[radsrh]

Re: Fuel restriction on 94 honda bf35

Look at the primer bulb, to me it sounds like it could be a bulb problem ie installed backwards or even a bad bulb. A air leak would not collapse the bulb and a bad pump should not be able to pull the bulb in. I am wondering if you don't have a new problem, you fixed one with the new fuel lines ect possibly a bad vent on the old cap and then made a new problem with a bad fuel bulb. When the problem first started did you have the problem with the bulb going flat?

 

[fish hed]

Re: Fuel restriction on 94 honda bf35

Radshr- Yea I didnt have the problem with the primer bulb collapsing with the old bulb. The new vent cap is alot tighter than the old also, but it fits, tight but the vent should still work the same right?. I went from 5/16 to 3/8 fuel lines when I switched up. Maybe she will cooperate tomorrow with some new plugs and a new male quick connect. Thanks for the insight and I'll keep you guys posted.