1986 Evinrude 90hp problems

[kc2hlq]

Hello.<br /><br />I have a 1986 90hp Enivrude. Any tips to be able to tune it up and get more power out of it. I can only get 4000 rpm while I'm in gear. If its in idle I can get more. Other than that the engine runds fine. Also I can never get it to start with just the turn of the key. Even after its warmed up. I always have to give it throttle. Its not the spark plugs, I've changed those. What else could it be? <br /><br />Thanks

 

[DJ]

Re: 1986 Evinrude 90hp problems

kc2hlq,<br /><br />Your engine sholuld turn a MINIMUM of 5500 RPM at widre oipen throttle to perform properly.<br /><br />The reasons that you cannot achieve that may be several.<br /><br />1. What is the compression of each cylinder.<br /><br />2. When weas the last timew the cuarburetors were serviced (rebuilt).<br /><br />If number 1 is OK, then I would be looking at number 2.

 

[JB]

Re: 1986 Evinrude 90hp problems

The first thing you need is a Manual.<br /><br />Revving a 2 stroke engine with no load (in Neutral) is a fast trip to destruction. Never do that.<br /><br />Once you get your manual, ensure that your engine is getting full throttle and ignition advance, is running on all 4 cylinders and is correctly tuned.<br /><br />There is a good chance that you are severely over propped.<br /><br />Let us know what yolu find.

 

[eula30]

Re: 1986 Evinrude 90hp problems

Ks2hlq, <br />I had the same starting problem with my motor. I finally did figure it out what I was doing wrong. What I do now is this: before starting the motor, I will turn the key but not all the way to start the motor just half way then I’ll bring the throttle lever up half way I’ll push the key in ones and let go (Don’t hold the key in to long or you will over floe you carburetor) then I’ll start the motor, motor will start right up, if you think the motor will want to go off just push the key in once before the motor goes off and just keep doing the same until you get use to it. <br /><br />Kc2hlq, With this motors you will have to bring the throttle lever up to a quarter or half way before starting the motor all the time. This is the way I’ll do it and never fail my motor will start right away if I do it like this. Hope this help.<br />Thanks

 

[kc2hlq]

Re: 1986 Evinrude 90hp problems

compression is good.<br /><br />will doing a decarb help?

 

[ob]

Re: 1986 Evinrude 90hp problems

kc2hlq,Tell us what your starting procedure is.Do you pump the fuel primer bulb until it is firm before cranking?Do you push in on the key primer while turning the ignition switch to start when engine is cold?What lenghth,and style boat is the engine pushing?What diameter and pitch prop are you currently using?A decarb is not going to remedy the issue you have now but is recommended once you can pinpoint and cure the problem at hand.You say compression is good.Do you have some numbers for us?