88 Evinrude 120HP V4 VRO bogs at WOT Help!

[BAJA37]

1988 Evinrude 120HP bogs at WOT. I mean I'm flying along at full speed and clunk. Intermittent can happen one day but not another. Feels like I hit bottom but engine doesn't rev or run away or like I hit the brakes if I was in a car. It starts to stumble and I pull the throttle back and it almost stalls then I can go again. I rebuilt the fuel pump several years ago and took it apart the other day but it looked fine. I can't find the rebuild kit for this motor and was told that it's not made anymore. I pulled each plug wire one by one and rpm's went down. Carbs have never been serviced or rebuilt. Sat out all of 2000. Ran it last year and had same problem as this year. Primer bulb gets hard after 5-10 squeezes. Help Please!

 

[JB]

Re: 88 Evinrude 120HP V4 VRO bogs at WOT Help!

Howdy, Baja.<br /><br />Could be water in your fuel tank.<br /><br />Could also be an intermittent connection somewhere in your ignition.<br /><br />Good luck.

 

[BAJA37]

Re: 88 Evinrude 120HP V4 VRO bogs at WOT Help!

JB,<br /><br />thanks for the reply. if it's water in the tank how do i get it out? how does it get in the tank? does it keep forming like condensation? would you rule out carb problems? thanks

 

[JB]

Re: 88 Evinrude 120HP V4 VRO bogs at WOT Help!

Hi, Baja.<br /><br />Water often condenses in fuel tanks with changes in temp and humidity.<br /><br />The best thing to do is install a water seperating filter between the tank and the bulb.<br /><br />I doubt that both carbs would misbehave in the same way at the same time. <br /><br />Good luck.

 

[bajaboy]

Re: 88 Evinrude 120HP V4 VRO bogs at WOT Help!

i'm having the same problem with my 85 115 johnson, except that this year it finally got to the point i can only go about 100 yds at full throttle then it dies. seems like a fuel problem since it doesn't kill instantly? i've been through the gas tank, oiltank, lines and fuel filter. nothing. going in the shop this afternoon. i'll let you know what they find.

 

[BAJA37]

Re: 88 Evinrude 120HP V4 VRO bogs at WOT Help!

yep 100 yards is about how long mine will go before abruptly stopping. please let us know what the shop finds out. thanks.

 

[BAJA37]

Re: 88 Evinrude 120HP V4 VRO bogs at WOT Help!

JB,<br /><br />i never realized water in the fuel could cripple a motor so suddenly and only at high speed. i have owned this engine for 13 years and it's never done this before last year but i will be sure to install a water separator filter.

 

[BAJA37]

Re: 88 Evinrude 120HP V4 VRO bogs at WOT Help!

^

 

[Solittle]

Re: 88 Evinrude 120HP V4 VRO bogs at WOT Help!

By all means get the filter - your real problem, seems to me, is old bad gas (you said since 2000) and until you get rid of ever drop you will be chasing this problem. How you do it will depend on your boat gas tank etc, etc. Even if you have to pay some one. You will probably also be faced with a rebuild of the carbs due to the old gas. <br /><br />Been there & done that.

 

[BAJA37]

Re: 88 Evinrude 120HP V4 VRO bogs at WOT Help!

SoLittle,<br /><br />the boat was not run from when i winterized it in september of 1999 until may of 2001. i did not put stabil in the gas tank but i never did before. i ran the gas out of the engine and fogged the cylinders and drained and refilled the lower unit like every other year. the boat was used last year all summer and i have the same problem this year. deposits may have formed in the carbs in the year and a half it sat. the old gas is long gone but the repercusions may yet remain.