Problem with 1998 Johnson 70hp outboard

[syost]

Hello,<br /><br />I am having a problem with a 1998 Johnson Outboard I just bought. I took it out the weekend before last and when I first launched it worked fine. I went around the bay for a while at higher speed. Then went and got bait then started fishing. I went to move and it started acting up. It starts up easy, But when I begin to give it throttle it starts to go then dies. I end up having to pump the ball which is sometimes full and sometimes not. From this point on it countines to have the same problem. I took it home. Went out yesterday. Samething ran great when I got there then started doing it again after I sat for a while and started to move again. I would think could be the fuel pump which was already replaced according to who I bought it from. The VRO is disabled and I am mixing fuel 50-1. But if it is the fuel pump why does it work then stop?<br /><br />Any help would be awsome.<br /><br />Thanks.<br /><br />syost

 

[JB]

Re: Problem with 1998 Johnson 70hp outboard

Hi, Syost.<br /><br />Is the vent open on your fuel tank?<br /><br />Go to www.outboardrepairs.com and look for power loss.<br /><br />Let us know what you did and what happened.<br /><br />Good luck.

 

[syost]

Re: Problem with 1998 Johnson 70hp outboard

Yes, I have also tried switching gas tanks. What else I should have said is that after it starts actinh up it throttles faster then slows down kind like if you were push down on a gas peddle then take your foot off then down again ect.<br /><br />Thanks

 

[DJ]

Re: Problem with 1998 Johnson 70hp outboard

syost,<br /><br />I have seen this first hand and read about with othere on this forum.<br /><br />In each case, a carb. rebuild remedied the situation.<br /><br />Although, first off, try replacing the primer bulb.

 

[syost]

Re: Problem with 1998 Johnson 70hp outboard

Djohns19,<br /><br />Thanks for the reply. Its is a new Fuel hose. I do not know much about this stuff. How much does it cost if that is the case<br /><br />Thanks

 

[DJ]

Re: Problem with 1998 Johnson 70hp outboard

syost,<br /><br />I don't know how handy you are, but why not do it yourself.<br /><br />Figure:<br /><br />$30.00-manual<br /><br />$75.00 for parts.<br /><br />Othjrwise, I would bet a shop would charge at least four hours for the labor. Parts price would be similar.

 

[ob]

Re: Problem with 1998 Johnson 70hp outboard

syost ,Another possibility of your symptom is carb adjustment.Insure that the carb linkage roller is aligned on center with scribe line on fiber cam and "just touching" when controls are in neutral.One other possibility is that the mix screws on each carb are running a bit lean.If you screw them in all the way counting the turns you can determine where they are set at.Mine were originally set open 1 3/4 turns and engine had same symptom as yours.They are now set right at 3 turns open and no more flat spots on accelleration from stop.Also if VRO has been bypassed on your engine ,insure that the oil line or nipple on the oil half of VRO is capped or plugged off with a good seal.Good luck