Fuel problems!!

[macojoe]

Hi guys I hope you can help??<br /> I have a 1989 175hp Yamaha model 175ETXG This is a new to me motor. I have it on a 1974 Wellcraft V20 that I have converted from a I/O to a outboard Via a Gill Bracket. <br /> http://members.fishingworks.com/macojoe/ <br /><br />Problem is when i go out in the boat and try to run WOT the ball on the fuel line collapises and I get no fuel?? I removed the fuel caps to see if they were venting and they were. I tryed runing the boat with the caps off still the same happens?? Ok then I must have a rectriction some were?? I came home and put another brand new filter. Went again and still the same?? <br />This is went I got mad and removed both the tanks and washed them out, blew air thur them put new fitting(were corrodided) I blew all the vents and hoses out from the motor to each tank. I put brand new bulb, and yet another New filter. There are no anti-sphion balls or other restrictions of any kind.<br />The boat has two 20 gal tanks ,one on each side of the boat. The hoses go to a switsh so I can pick which tank I want or shut them off. Then to the water fuel filter then to the motor. <br />Well I went out again today and guess what the same darn thing?????????/<br />I am lost please help!!<br />Thanks

 

[BF]

Re: Fuel problems!!

Seems to me like you still have a fuel restriction problem between the primer bulb and the tank. Even though there might be enough flow for low RPM's, the resistance is enough that when more fuel needs to flow (at higher rpms), it's easier for the fuel pump to collapse the primer bulb than to draw from the tank. I would look at the fuel selector switch (try bypassing it), and the fuel/water filter. I would bypass each of these one at a time and to see if they're the cause of the restriction. If it's still there, then I'd try dropping a new/temporary fuel hose directly into the tank, bypassing the normal fuel line pickup in the tank. Venting's not the problem (same thing with caps off). Last thought... maybe the existing fuel line is just too small in diameter? Even if it's unobstructed, it could take a lot of suction to draw through a thin line (and bulb would collapse instead).<br /><br />Hopefully this fuel problem wasn't why the I/O was ditched! <br /><br />Brent

 

[macojoe]

Re: Fuel problems!!

Thanks BF! I have a 3/8 fuel line on the whole thing. I have blew the hole system out with wir and all seems well. I will try by passing the switch. The water seprator is a whole bran new system and yes I have it flowing in the rt direction. <br />The I/O was oringal 1974 and plagued with problems!! And I being a outboard guy till this boat decided that was they way I wanted to be again. I never had a problem with the fuel when it was a I/O.

 

[macojoe]

Re: Fuel problems!!

tryed by passing the switch and the filter and put on a 6 gal tank still the ball goes flat???? <br />Does fiberglass smoke much when it burns??? Because there is going to be a fire soon if I don't get this thing going!!

 

[DJ]

Re: Fuel problems!!

maco,<br /><br />In addition to the others suggestions, all good ones.<br /><br />Boat fuel tanks have an anti siphon valve in the fuel pick up in the tank. Sometimes it is part of the pick up tube, sometimes it is a seperate component in line at the tank.<br /><br />The best test is using the seperate 6 gallon can.