Motor cutting out?

[herefish101]

My outboard has been running great this year, that is until yesterday, now whenever I push it past 3/4 throttle the primer bulb starts to go flat and the engine starts to starve for fuel, if I stop and let it fill up again and then squeeze the bulb a few times it starts right up. The tank vent is open. I just don't understand what causes this and how I fix it, i'm hittin Mille Lacs next weekend and I would like to figure this out before then, thanks to anyone with any advice.

[Ufatz]

I'm no expert but you may have TWO problems, the first of which is easy to solve. You have an air leak in the fuel line or around the bulb. I have in the past just replaced the whole assembly and saved time. You may wish to check all connections at motor and tank. Check bulb carefully. That is probably all you need to do....new line and bulb, or at least bulb.

Why it is doing it when you accelerate could have several causes, but I'll bet the above changes will solve that too.

Other more knowledeable guys will chime in too.

[herefish101]

if there were aan air leak in the line would'nt that just allow air into the bulb thus loosing it's prime? On mine the bulb is being sucked flat, like a pancake. Or would air in the system cause this. I guess i'll replace the entire hose assembley and hope that fixes it.

Any more ideas/info i'm open to all opinions. Thanks.

[jentz]

Same question on other sites I see.Cant delete this post??

[herefish101]

Same question on other sites I see.Cant delete this post??

What does this even mean? So I posted the same question on multiple forums trying to get my problem fixed before it screws up my fishing trip next weekend. Are you calling for it to be deleted? Why would you even post on this topic? Please, i'm looking to fix my problem here not argue about my post.

[Bigtom]

if there were aan air leak in the line would'nt that just allow air into the bulb thus loosing it's prime? On mine the bulb is being sucked flat, like a pancake. Or would air in the system cause this. I guess i'll replace the entire hose assembley and hope that fixes it.

Any more ideas/info i'm open to all opinions. Thanks.

If you had a crack in the line the bulb would not be flat. The bulb is getting squezed flat meaning the motor has good suction and is getting starved out of fuel. It could be plugged or kinked or a bad conecter.

My would be to check the conecters or if money it not the object replace the whole works depending on the age of it. Good luck!

[kerryd15]

If the bulb is going flat there is an obstruction between the bulb and the inlet.depenting on the tank, check your conection at the tank. if that is good, see if there is a way to check the inlet tube for blockage. you could try running with the cap off or loose to rule out the vent.

[boatfixer]

Herefish, we welcome your questions here.

Kerry is correct in that there is more than likely something impeding the fuel flow between the bulb and the pickup screen in the tank. It could be the screen, anti-siphon valve, pinched line, etc, or even the inlet side of the bulb.

If you have access to another tank and line, you could swap out each one to narrow it down.

[jentz]

herefish101,,,,Sorry I got a BIL who got abit angry with me plagiarizing his answers so I remover it.

[RIPN LIPS]

2002 yamaha 150 2 stroke has had the same problem. so far i've replaced the fuel line and i am in the process of cleaning the three fuel filters on the engine and am going to try and run it off of a 6 gallon tank to see if its in the motor or if its the gas tank in the boat. i've herd guys taking the anti siphon out but i do not recommend this as i have done that and that was not it. good luck and post your finding please.

[herefish101]

Thanks for the fresh ideas, I'm about to dig into the tank and see if there are any obstructions, Thanks again.

[JohnD]

The first thing we need to know is what make and model is the motor?

I had the exact same problem with my 2004 Mercury Optimax, it turns out I didn't have ethanol resistant fuel lines and the ethanol had deteriorated the lining inside my fuel lines and plugged the fuel line, bulb, and fuel filter. After I changed all three of those items it runs like brand new.

If you have a Mercury motor and have anything other than the new ethanol resistant lines (Gray with BLUE Writing), you need to change the lines, bulb, and fuel filter.

[BrandonN]

Motor issues are never fun

[Surface Tension]

The first thing we need to know is what make and model is the motor?

I had the exact same problem with my 2004 Mercury Optimax, it turns out I didn't have ethanol resistant fuel lines and the ethanol had deteriorated the lining inside my fuel lines and plugged the fuel line, bulb, and fuel filter. After I changed all three of those items it runs like brand new.

If you have a Mercury motor and have anything other than the new ethanol resistant lines (Gray with BLUE Writing), you need to change the lines, bulb, and fuel filter.

I agree.

The collapsed bulb means the fuel pump is working like it should but there is restriction in the fuel line between the fuel pump and gas tank. As said the check valve on the end of the pickup tube in the tank could be one culprit. As also noted the inside off the fuel line itsself can deteriorate from oxygenated gas and case a plug. I've also seen supposedly fuel resistant lines go bad where interior lining rots out and that usually happens on the ends where there is a fitting. I'd go to NAPA and get UV resistant fuel line in the correct diameter. The UV rating is for a fuel line that will be in the sun. I mention the correct dia because too small of fuel line will cause restriction as well and you'll notice that when you ask for more power. The check valve and pickup line in the tank is easy to remove but you can't just replace the fuel line there . While the brass fittings are barbed you need a crimp on band clamp to secure the hose to fitting because a regular hose clamp won't pass through the hole in the tank.

Just thought I'd let you know that now. You'll have to buy a new dip tube and check valve or have one made up. Or maybe you will get lucky and the hose will be fine and the check valve just corroded and cleaning it gets you back in action.

[boatfixer]

The restriction is between the bulb and tank pick-up inside the tank. This could include the inlet check valve in the bulb.

[RIPN LIPS]

did you find the fix for your motor??