Hi guys

In dire need of some help from some of you gurus.

Went out fishing today and had to crawl most the way home due to fuel starvation issues. Really frustrating experience.

Symptoms are as follows: Problem occurs at high revs, outboard loses all power. Engine doesn’t die but just loses all revs. After this the outboard seems fine at low revs but once we try to open it up a bit it loses power again. The bulb collapses and takes forever to return to full shape after pumping.  

Outboard is a 98 Evinrude Oceanpro 115. Underfloor 230L fuel tank. There is a vent on the tank and an in-line water-separation filter. Tried sucking on the vent and it seems to be clear.

I’ll give you some history.

Bought the boat 3 months or so ago. Originally had a fuel flow gauge fitted. There was a very minor fuel starvation issue on the test run. The seller said it was a problem he had experienced before and that it was an airlock in the fuel flow gauge. To fix it he opened up the fuel line where it connected to the fuel flow gauge and blew in it. Seemed to work.

Talked to the shop who did the pre-purchase inspection about it and they were pretty certain it would be the fuel low gauge not being orientated right.

Once we got it home we repositioned the gauge and had a number of problem-free trips. Then at a later stage the problem showed up again so we removed the fuel flow gauge. This seemed to work for a while. However, a couple of weeks ago we had the problem rear its head again (flow gauge no longer connected). I opened the fuel line and blew in it (clutching at straws I know) got us through the rest of the trip and the next.

Today the problem showed up again big time. Managed to get home by continually pumping the bulb and disconnecting/reconnecting the fuel line at the bulb when it started to collapse.

Might also be worth mentioning that we sometimes have problems filling the fuel tank. The gas station pump often won’t stay on and we have to hold the pump handle down in order to get it to fill.

The collapsed bulb makes me think it is a fuel line issue rather than an outboard fuel pump issue (but I don’t really know what I’m talking about). Thinking it could possibly be the fuel filter so will replace this ASAP.

Anyone have any other bright ideas???????

A few places to start. 

Or crud/ plastic in the tank blocking the outlet,this would explain the randomness,when its blocked the pump is sucking the primer bulb flat as it cant get enough fuel.
Had this on my wife's BMW car ,very easy fix in the end that had me thinking big $$$, small piece of plastic on tank strainer that must of dropped off when car stopped then picked up at higher revs

Hey guys 

Might also replace the fuel lines between tank-filter and filter-bulb to be safe.   

Had a very similar scenario with our 175 honda. The fuel line was crushed by salt build up at the point of entry to the motor itself.    I clean it out every year now.    Damn I wasted some time checking this line, that filter, this tank that tote.    Simple fix in the end.

The problem is the issue only seems to occur after a while of travelling
Bulb sucking in
The pump must be working to pull the bulb in and no air leaks between the bulb and tank
u blow back down into the tank, runs fine.. for a while

Any debris that maybe causing the blockage gets blown back out... into the tank.
OR and perishing , disinergation of the inner lining of a fuel hose gets blown back out...or  flap blown back.
A common issue on 'home' repairs, for cars is not using the correct vaccuum type fuel hose

From your description it wil be either wrong type or perished hoses, blocking or sucking closed
OR crap in the fuel tank...
illustrate this, an old dirty trick was to put feathers in a car fuel tank... car runs fine but as the feathers get close to the tank pick up they collect and eventually block... stop and they float away...

Replace the fuel filter, regardless of how old....pour the contents out and open it up for inspection

Replace all hoses from bulb to tank.. at least.. if they are the wrong spec because of poor previous workmanship, may pay to replace the lot just incase.. and check the filler hose to tank, for spec and inside condition

And caustion tunning a engine of that size on a tote take WoT....many totev tanks are designed for small engines and the fittings dont flow enough fuel, and could run lean.

Get this sorted very soon... running lean/ running out of gas is very destructive to engines

RE If the issue turns out to be crap in the fuel tank how would I go about cleaning it out??


A garden hose used as a syphon with the end in the tank moved all around the bottom would suck the crap out like a vacuum.

Steps wrote: Pull the tank out.... yeah sounds like a big job.. but once have a few jumble clips undone, couple guys.. MT it, remove the sender unit.. chances are the screws will be stuffed so may have to get the drill or grinder out to remove them....  a good flush with a hose... Drain , a 1/2 L meths, good rinse out .. The meths dissolves any moisture. repeat again.... Throw a couple L premixed 2 stroke in, rinse out.. and if all clear replace the tank And while at it replace all hoses... And dont buy the hoses at a marine place, they charge like a rabid wounded bull on heat. Automotive supplies.... I will make something clear here.. for the last 40yrs I have not been a 'boat' person, more classic/  vintage/ muscle cars.. but the principles are the same

Gizzy, to clean the tank thoroughly you may have to cut an inspection panel in the top of the tank if it does not have one now. There is no easy method for getting inside a fuel tank and getting everything out of it. If the tank is baffled make the inspection port to cover each side of the baffle.