1990 40hp VRO Evinrude won't idle

[casracing]

I got a 1990 40 hp Evinrude that won't stay running for more than 20-30 seconds without me pushing in on the choke, and it runs rough. My mother in law let it sit for over a year. After I got it the carb gaskets were shot, and it wouldn't start. So I got a rebuild Kit and rebuilt them myself also got a clymer manual to help me out. I have replaced fuel lines, spark plugs, fuel filter, readjusted the floats 3 times. The carb kit said to set them 3/4 of inch and the manual sais 1 1/8-1 5/8. I recently just maxed them out. I have got a puddle on the ground and trying to decide to look at the reed vavle to see if helps. any help would be appreciated. thanks

 

[fireman 757]

Re: 1990 40hp VRO Evinrude won't idle

Set your float so it is level with the carb when turned upside down. That should take care of the puddle. Did you make sure that there is absolutely nothing in the high speed jet? Does the primer bulb get hard and stay hard? Have you tested for spark to the plugs yet? Sounds like you missed something in the carb. Chances are it is not the reed valves. these very rarely go bad.

 

[casracing]

Re: 1990 40hp VRO Evinrude won't idle

I have got spark to the plugs, have adjusted the float to be level. The primer bulb stays hard. Is the high speed jet the one in the fuel bowl? My book doesn't show it. And I didn't make sure it wasn't clean. Just assumed when I blew it out with carb cleaner. I'll try running a thin piece of wire down it. I was wondering if I overlooked an air leak somewhere

 

[fireman 757]

Re: 1990 40hp VRO Evinrude won't idle

The high speed jet is the long skinny one. Any piece of debris will cause your "no go" problem. Doesn't sound like an air leak if the primer bulb stays hard and you are getting fuel to your carb. The puddle has to be caused by the float sticking and allowing your carb to over fill. Did you replace the needle valve and seat? If not I would as if the needle valve is stuck then your float will stick too. I have had very little success in cleaning them up. It is cheaper and less time consuming to replace them. The kit is under $20.

 

[casracing]

Re: 1990 40hp VRO Evinrude won't idle

Thank you for your help. Tonight I finally got it start and stay idling. I pulled both carbs off and sat down and pulled them apart. Sprayed carb cleaner in evry orfice and ran wire through the jets. Reset my floats to 1 1/8 and stuck them back on. I had to guess at what to set the low speed jet. My manual only gave for 25-30 hp and 35 hp. I set them at the 35hp setting and kept bringing them out 1/2 turn till it stayed idling. Thanks for the help.

 

[casracing]

Re: 1990 40hp VRO Evinrude won't idle

I feel like an idot. After putting on the engine cover the motor won't stay idling very long. It runs very rough. However if you put it in gear and gas it it will go. My carb rebuild kit said to set the floats at 3/4" And my manual only gives me for 20-35hp. I set the floats at 1 1/8 is this wrong? And could the engine be running lean at idle? I have the low speed screw turned out to 3 turns. I believe I read somewhere that it should be 1 turn. The primer bulb is staying hard. I replaced the line. And does anyone know where to set the timing intially? My manual tells me how to do it and 5000 rpm. However I'm worried about taking the boat out on the lake and it not taking me back.

 

[hondon]

Re: 1990 40hp VRO Evinrude won't idle

Basically for this engine the float levels are set level with the bare float bowl flange with the carb inverted.Thats eyeball level from all angles and will meet the qualifications of even the special tool OMC would like you to use.Carb cleaning leaves some ?s.Were there any core plug removals? If not then you did not do a complete job of cleaning this carb.If you do not have a manual to set the intial idle mixture then you do not have a manual to set the timeing and carb sync of this unit.That setting alone can make this thing idle like crap.

 

[casracing]

Re: 1990 40hp VRO Evinrude won't idle

The manual I have is a Clymer B732 2-40hp 1973-1990 Evinrude/ Johnson Is this the wrong manual? It was the only one I saw at my Marina. Or I just not looking in the right spot

 

[casracing]

Re: 1990 40hp VRO Evinrude won't idle

Thanks for the help. I had it on the lake today and ran it for 2 1/2 hours no problems. The only thing was it a little cold blooded and didn't want to stay idling for about 4-5 minutes

 

[Chris Wilson]

Re: 1990 40hp VRO Evinrude won't idle

We had similar problems with our 1991 and had the carbs rebuilt. Sounds like you are on your way.<br /><br />However, as a hint to keep in the back of your mind if it just doesn't seem quite right yet, we also continued to have low idle problems after the rebuild and some variation in speeds at higher rpm. It turns out our thermostat was stuck open and the engine was overcooling. We purchased new one and the improvement was DRAMATIC. The manual says that tempaerature is critical but I thought they were mostly concerned about overheating (which we all agree is important) but running too cool was not on my radar screen until I started to read the manual closely. They even suggest tests to make sure the operating temperature is in a range - not just under a maximum temp.