90 hp Evinrude -- Fuel Problems??

JIS1974

Cadet
Joined
Jun 2, 2002
Messages
11
I just bought this motor. 1984 90 hp Evinrude E90 MLCRD It has the VRO option (there is a seperate tank for the oil.) The previous owner obviously had some problems with it; the spark plugs and coils are new. Previous owner ran it "a couple of times over the last three years." So, before I ran it, I siphoned old gas out of the tank and refilled with new gas.<br />Problems:<br />The engine is a little difficult to get started and once it finally starts the engine will not idle without the fast-idle lever up. (This makes it rather difficult to get into gear!) Once I get it into gear and slowly accelerate, the engine "misses" a little. ...as if it isn't hitting on one of the cylinders. <br />Once I get the engine up to about 3000 RPM (about 25 mph for the boat) the engine will slowly sputter down and die. If I wait about 5 seconds, it'll start back up again. Sometimes, it'll be sluggish to crank over when this happens. (I have a brand-new battery.) It'll run fine as long as I keep the RPM below about 3000. The engine is not getting excessivly hot and there are no buzzers or horns sounding. The tell-tale jet is strong. There are no funny smells or sounds. There are no fluids leaking in the engine compartment (that I can see.) All the linkage seems to be working fine. <br />What I've done so far:<br />Replaced the fuel filter. Replaced the fuel line from engine cover to tank (including the bulb.) Removed, flushed, and re-installed the gas tank. I've checked the tank vent; it's not blocked.<br />What do I do now? Is this a common problem with an easy fix?<br />Any and all help would be appreciated.<br />KS in TN
 
Joined
May 22, 2002
Messages
27
Re: 90 hp Evinrude -- Fuel Problems??

Did you clean the carbs?<br /><br />You might have a blocked high speed jet. Depending on the design of the carbs this would also contribute to the hard starting and lack of idle.
 

JIS1974

Cadet
Joined
Jun 2, 2002
Messages
11
Re: 90 hp Evinrude -- Fuel Problems??

I'm working on rebuilding the carbs now. Any suggestions or tips would be helpful. <br /><br />As I was removing the carbs I noticed the "clear" oil tube that goes to the VRO unit was cracked/broken. It is fragile with age. I'm not sure if it was broken prior to my tugging on the fuel line... It needs replaced if I'm to continue using the VRO system. Any ideas where to find this part? If this was broken prior to my tinkering what would be the "symptoms" of the motor? Would they be similar to what I've described previously? Should I run a compression check to make sure there was no damage? ...sorry for all the questions; I'm new to outboard motors.<br />KS
 

Terry H

Lieutenant Commander
Joined
Sep 25, 2001
Messages
1,862
Re: 90 hp Evinrude -- Fuel Problems??

Kansas...I would definately do a compression test. You could have been sucking air instead of oil. If compression tests good I would plug the vro where the oil line hooked into and primix some fuel and run thata way until you get the bugs worked out, then if you like the vro feature get it working properly and use it. <br />Sounds like you do have a fuel delivery problem, check all the little crevices and holes in carb make it spotless. Check all the spark plugs for good spark and good clean plugs...if all is good run it on premixed fuel. If the problem stays try pumping the primer bulb when motor starts to slow...if that helps you might need fuel line parts or fuel pump...just a Thought
 
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