Engine dies after long runs (fuel issue), fuel hose?

[ShawnQ]

A few times when I was on the lake last, if I would run the engine for a few miles, and then start to idle around (watching the depth finder), and then try to take off again, it would act like it had no fuel. So, naturally, I would go check the primer bulb, pump it up, and go for it. The bulb would be deflated each time.<br /><br />I replaced the bulb, and had the same problem (not everytime though, which is what is weird.<br /><br />Any idea on what may cause this? Could I have a kink/pinhole in my fuel line? I did notice that my fuel line does make a 270* turn from the rigging tube to go out of the access hatch, and to the outboard. But, everyone with my boat has this...and it works for them.<br /><br />I can't see any fuel leaks anywhere, so I am against the idea that there is a pinhole.<br /><br />Maybe my fuel pump? Filter is clean.<br /><br />Thanks for any help!<br /><br />Shawn

 

[Paul Moir]

Re: Engine dies after long runs (fuel issue), fuel hose?

Shawn, if the (presumably good) primer bulb is going flat, that would point to a constriction somewhere up the line. Likely candidates are:<br />1) The water/fuel separator (if you have one)<br />2) The fuel vent blocked. This causes the outboard to suck a vaccum on the tank, since no fresh air can get in, but gas is being consumed.<br />3) Clogged fuel pick up tube in the tank. It normally has a screen on the end of it.<br /><br />I'm guessing 2, since it usually takes a while to empty out the tank enough to stop the engine.

 

[roscoe]

Re: Engine dies after long runs (fuel issue), fuel hose?

Your fuel pump appears fine. It is strong enough to suck the primer bulb flat.<br /><br />If you had a pinhole, it would be sucking in air, the bulb would not go flat, and fuel would not reach your engine.

 

[ShawnQ]

Re: Engine dies after long runs (fuel issue), fuel hose?

Thanks for the help.<br /><br />On a sidenote, I did pull my fuel tank yesterday so that I can go ahead and apply durabak to my boat.<br /><br />So, now that it is out, I can access it easily. I already need to change the sending unit, so that could kill 2 birds with 1 stone.<br /><br />Shawn

 

[ShawnQ]

Re: Engine dies after long runs (fuel issue), fuel hose?

Ok guys, I replaced the sending unit and checked the fuel pickup on my fuel tank, and the pickup looks clean. There was a small amount of debris, but not enough to hurt anything. Cleaned it all up and put it back in. The vent tube is clear, no blockage or kinks at all, easy airflow. The filter is clean/clear, and there is no water seperator. <br /><br />After that, I took the boat to the lake and coast this weekend, and I am having to prime the bulb to keep the engine idling for any period of time over 30sec-1 minute. If I idle longer then that, it will eventually buck, run rough, then die. Prime the bulb (which is very soft), and it will fire right back up.<br /><br />It NEVER runs bad when I am hauling @-$-$, only when idling...this is what messes me up. I would think that it would be the other way around. It runs great when not idling, no kind of miss or anything, 5200+rpm all day long without skipping a beat.<br /><br />What would cause a low RPM lack of fuel, but not a high RPM lack of fuel? I am guessing that there is a blockage somewhere and at higher RPM, the pump works harder and can keep up better.<br /><br />One other thing: My fuel line takes a few odd turns, goes up hill a bit, and what not...would this hurt it? It isn't kinked at all, but it does go uphill and turn a little bit...but I assume everyone elses does too.<br /><br />Maybe I'll buy another fuel bulb, I assume the one I bought could be defective. Is there any way to test them?<br /><br />Thanks for any further help.<br /><br />Shawn

 

[Duck Loads]

Re: Engine dies after long runs (fuel issue), fuel hose?

A year ago, I bought a bulb from WallyWorld the was junk out of the package. It wouldn't stay tight. I chased fuel lines till I turned blue and found nothing. I bought a genuine OMC (Bomb) part and havn't had anouther problem. Just a thought.<br /><br />Be safe,<br />Duck L.

 

[Joe Reeves]

Re: Engine dies after long runs (fuel issue), fuel hose?

Shawn.... What you're describing is a fuel restriction, usually caused by the following.<br /><br />NOTE... It would help if you stated just what engine we're speaking of.<br /><br />(Fuel Anti Siphon Valve)<br />(J. Reeves)<br /> <br />Many of the later OMC V/6 engines incorporate a fuel restriction warning via a vaccum device attached to the powerhead. If the engine overheats, or if you have a fuel restriction, the warning is the same.... a steady constant beep.<br /> <br />NOTE... Only the V/6 & V/8 engines have the above "Fuel Restriction Warning". The warning horn will not sound on the other models. <br /><br />The fact that a engine is not overheating, but the warning horn sounds off with a constant steady beep, and that the rpms drop drastically would indicate that the engine is starving for fuel due to a fuel restriction. Check the built in fuel tank where the rubber fuel hose attaches to the tank fitting. That fitting is in all probability a "Anti Siphon" valve which is notorious for sticking in a semi closed position. It will be aluminum, about 2" long, and the insides of it will consist of a spring, a ball, and a ball seat. If this valve exists, remove it, knock out those inner components which will convert it to a straight through fitting, then re-install it. Hopefully that cures the problem.

 

[ShawnQ]

Re: Engine dies after long runs (fuel issue), fuel hose?

Duck,<br /><br />The bulb I bought is from wally world...I'll go get an OMC one just to check it.<br /><br />Joe,<br /><br />I believe that my fitting is a standard brass pipe fitting. I've got an aluminum tank under the console, and I don't think there is a valve in the fuel line fitting. I will look though.<br /><br />BTW, it is a 1995 Evinrude 88spl<br /><br />I did get a buzzer while at the lake this past weekend. The engine did not seem to be overheating, but I shut it off anyways. I did have it raised up pretty high because I was going through some very shallow water with a lot of stumps (after white bass), and I thought maybe the impeller itself was getting warm? The water from the pee hole was just about as cool as the river water (70* or so, not hot at all). I wasn't sure why it was doing it, maybe cause of fuel? I shut it off for 30 seconds, and re-fired, but i lowered the engine a bit...no more buzzer. It was running about 5psi at idle, and it runs 20-25 at WOT. I didn't have the engine all the way out of the water, I know better then that...the cavitation plate was still covered, and nothing was clogged.<br /><br />Thanks for the responses!!<br />Shawn

 

[ShawnQ]

Re: Engine dies after long runs (fuel issue), fuel hose?

Guys,<br /><br />I think I've figured it out.<br /><br />I traced the fuel line AGAIN today, still couldn't find anything. Looked at and checked the tightness of all of the fittings, everything was fine. Disconnected the vent tube and ran air through it, it was clean. Disconnected the fuel line from the tank and from the primer bulb, and ran air through it, it was clean. So, I decided to re-install the fuel line, and run the engine on the water hose to see if it would idle for a long time. As I went to prime the bulb, I found something. Look at this:<br /><br />

<br /><br />Gas sprayed out and gave away what I hope is the culprit. I filled it up with water and red food coloring and it highlighted the crack so it would show on the camera. I ASSUME that this is my problem. I primed the bulb several times and it leaked fuel out of it. However, I don't remember it leaking fuel when we primed it at the lake and the coast. I assume that the crack could've been smaller, and just continually got larger. I don't know of anything we did after leaving the water to cause this...so I guess that the crack has just gradually gotten larger (the problem has become worse and worse as I've been using the boat, now that I think about it)<br /><br />Hopefully this is my problem, I will be on the water this weekend and will let you know how it goes!<br /><br />I've been doing good...I also figured out my electrical issue on my other post! <br /><br />Thanks for the help.<br /><br />Shawn