Attwood primer bulbs and fuel lines don't mix with the 50!

[Blindduck]

A few months ago I posted on here that I was having problems with my 2009 50 hp ELPTO running out of fuel at idle but fine at WOT. I have been rebuilding the fuel pump x two, replacing bulbs x 3, checking lines, and even replaced the tank. Nothing seemed to help. I realized today after more problems out on the water that this problem began when I switched the factory mercury primer bulb to a attwood replacement because the factory one had some dry rot on the bulb.

To find the problem today I put a fuel pressure gauge on the outlet side of the fuel pump and pumped the primer. The gauge pegs and then fell rapidly. Replaced the primer bulb with a brand new Mercury bulb that I bought today and repeated test. The gauge pegged out and held. Removed the gauge and reconnected the fuel line and the motor idled like a champ for 30 min when I shut it down.

Now I hate to bash a company on here but to my own stupidity I replaced the primer bulb two times and the bulb/line kit once all three times using the attwood brand. All three times the fuel was running back into the tank. My lesson learned, only use factory parts. This may not be the case with all motors but mine shure does not like Attwood primer bulbs.

Hope this helps someone down the road.

 

[michaud500]

Re: Attwood primer bulbs and fuel lines don't mix with the 50!

I am having fuel supply issues also. Are you saying that the Attwood( I have one also, brand new) doesnt hold the fuel supply? Mine seems to block the flow of fuel, not enough flowing through the fuel line??? I have a clear fuel filter so I can see the fuel supply. When I prime the bulb while running hard but not WOT. I feels like I cant get enough fuel to the engine.. Does this sound like it could be related to the primer bulb from your test?

Thanks

 

[Blindduck]

Re: Attwood primer bulbs and fuel lines don't mix with the 50!

It was not keeping the fuel in the line at idle speeds and when I would stop to fish it would also drain all the fuel back to the tank. Do you have to keep priming the bulb on yours too? If so the problem may be the same. Mine was fine at wide open throttle though. If you are haveing problems at WOT then you have something else going on. I lake tested mine yesterday and problem solved. Sorry I got back to you a little late. I did reply earlier in the week but I guess it did not go through.

 

[michaud500]

Re: Attwood primer bulbs and fuel lines don't mix with the 50!

sorry for the late response. Thanks for getting back to me! From what you are saying your problem is the opposite of mine. I think that there is either a restriction in the fuel system(primer bulb) or a air leak. I put a clear fuel filter in the line that the bulb in on, I can see the fuel flow. The filter never fills completely or even half way for that matter. when I am at WOT I will squeeze the primer bulb and there feels like no fuel is going through. The bulb hesitates to open back up when I squeeze it.This makes sense with the flow of fuel to the engine. I guess I am wondering if the Atwood primer is too restrictive for my engine, a 1969 merc 500??

 

[michaud500]

Re: Attwood primer bulbs and fuel lines don't mix with the 50!

I had the boat out WITH THE NEW Mercury primer bulb. It sure made a difference!! She ran much better but was not the cure all. I will keep tweeking.

 

[Blindduck]

Re: Attwood primer bulbs and fuel lines don't mix with the 50!

Good to hear. What is it doing now?

 

[adgunn]

Re: Attwood primer bulbs and fuel lines don't mix with the 50!

On my 79 merc 900, I had the same issue of good low end, but bogging down and stalling when trying to run at or near WOT...long story short, my fuel quick connects wouldnt even come apart on the engine. I cut the line and ran it direct to the fuel pump...bingo!! I can happily drag 250+ lb people on a tube with my pontoon!! Might be worth checking out...

 

[michaud500]

Re: Attwood primer bulbs and fuel lines don't mix with the 50!

She still dies out after WOT run and and idles a little funny after it also. The good part is that it wont die out on me at WOT. She will run at low idle for days before WOT. I went up a small river in a flowage last weekend the only time she putted out was when I got into some weeds. There has to be air getting in somewhere. I agree with adgunn about the quick connects. I replace a o-ring and some hose clamps to the plastic, crimp type to a more round type from the metal screw type on cars. That also helped with some fuel leaking and possible air leaks at WOT.

 

[25432]

Re: Attwood primer bulbs and fuel lines don't mix with the 50!

Atwood bulbs are crap, but.....if you will set it up such that the bulb is vertical instead of horizontal your problem will go away. The Atwood check valve requires the arrow to be pointing skyward for some screwy reason for it to function properly, the Mercury does not.

 

[Faztbullet]

Re: Attwood primer bulbs and fuel lines don't mix with the 50!

Its all because the Atwood has a single check valve and the Merc as 2 checks valves.....

 

[CharlieB]

Re: Attwood primer bulbs and fuel lines don't mix with the 50!

Most of the clear glass filters can be too restrictive for WOT running.

A spin on fuel/water separating filter is far better.

 

[Blindduck]

Re: Attwood primer bulbs and fuel lines don't mix with the 50!

Atwood bulbs are crap, but.....if you will set it up such that the bulb is vertical instead of horizontal your problem will go away. The Atwood check valve requires the arrow to be pointing skyward for some screwy reason for it to function properly, the Mercury does not.

Now why would they do that? Need to put that on the package. Or mabey they do????? I still have had no problems since after switching back to the Merc primer bulb

 

[25432]

Re: Attwood primer bulbs and fuel lines don't mix with the 50!

Now why would they do that? Need to put that on the package. Or mabey they do????? I still have had no problems since after switching back to the Merc primer bulb

They don't put it on the package. I figured it out in the middle of a cussing/kicking fit while duck hunting one morning.

 

[Captnlarry]

Re: Attwood primer bulbs and fuel lines don't mix with the 50!

Could the bulb be the problem when it just keeps flooding carb, too much pressure coming from bulb.
I've replaced carb and still have a flooding issue.

 

[CharlieB]

Re: Attwood primer bulbs and fuel lines don't mix with the 50!

Larry, this thread is way long dead. Start your own, tell us what you have, what it is or is not doing, and what you have done so far to try to figure it out.