98 30 hp evinrude 2 stroke problem

[chiefcatchemall]

Hey all, I just bought a 16.5 ft alumacraft fishing boat with a side console with a 1998 evinrude 30 hp 2 stroke on the back of it. It fires right up no problems. It idles down nice as well. This was my first time out with it and I noticed a problem. If I let the motor idle or if I trolled as slow as I could do I noticed that when I went to put the hammer down it would skip like hell and wouldn't take off like it should. It was real bad. And it would happen everytime I let it idle or put it into gear and went as slow as I could. Again, it would run fine when doing this but then when I went to gun it it would skip and shutter like hell. However if I put it back into neutral and reved it up 2 or 3 times in neutral then put it into gear and gave it full throttle it would take right off just fine. Once it's running wide open it runs like a top. I just want to get this one issue straightened out. Initially I thought maybe the plugs were loading up and hat I mixed my oil too rich but it wasn't the case. The plugs looked fine and for good measure I threw a new set in and it still was doing the same thing..

 

[jakedaawg]

As always, start with the basics. Fuel sample, compression test. I think you will end up cleaning the carb. Pay particular attention to the off idle circuit.

 

[chiefcatchemall]

New non ethanol gas mixed 50:1 and compression is 118 on both cyls. Hoping I just need a carb cleaning..looks like I need to remove the starter to get to one of the nuts that I need to remove to take the carb off

 

[boobie]

Yes you do......

 

[chiefcatchemall]

I have a question for some of you guys with more knowledge on these outboards. It may be a stupid question but here it goes...


Would it be possible that this particular motor has a safety feature on it that will not allow the motor to run above a certain RPM if it starts to slightly overheat? Here is why I am asking...

I notice that my motor isn't peeing water very well when my motor is at trolling speed or when my motor idles down as slow as it goes. But when I give it throttle it pees water better. I am only having issues after I let it idle for a minute or so or if I troll for any length of time. Which I am starting to wonder if it slightly overheats and puts it in some kind of safety mode


If I rev it up in neutral after I'm having this problem it increases the amount of water circulating through the motor(cools it) then all is fine and it runs like a top.


Could it be something as simple as an impeller that needs to be replaced or is this a stretch?

 

[jakedaawg]

Sounds like you need an impellar and a carb cleaning

 

[chiefcatchemall]

I dropped the lower unit and the impeller was in great condition. If I had a dirty carb wouldn't the motor run poorly ALL the time? It only runs poorly after I troll down or let it idle for a minute or more...

 

[jakedaawg]

There are several circuits in a carburetor. There is the Idle circuit, which controls air/fuel mixture when throttle is closed. Just behind the idle jets are the off idle holes. these act as air bleeds when throttle is closed but then despense fuel as throttle plate opens past them. They usually work in conjunction with a needle valve. After that there is the main jets.

Its possible, and even likely, that just one circuit is pluged up.

When people say your carbs need to be cleaned it simply means that all the little passages and holes neeed to be free from debris. Just because you pull a bowl off and it looks as good as your dinner dishes doesn't mean that there is not a tiny little piece of fuel line residue plugging up one tiny little hole. Those tiny little holes are there for a reason.

With skill and practice one can "clean" the carb/s on many engines in less than an hour and need no parts. I seldom need to buy a rebuild kit to clean a carb.

A good selection of fuel line is a must though. The stuff just doesn't seem to last anymore.

 

[chiefcatchemall]

Tomorrow I'm going to be pulling the starter and cleaning out the carb. I have had many apart before. I'll make sure all the jets gets sprayed out good and everything gets sprayed out good with compressed air..I'm still somewhat convinced that it's getting put into S.L.O.W mode for some reason

 

[jasper60103]

I have a question for some of you guys with more knowledge on these outboards. It may be a stupid question but here it goes...


Would it be possible that this particular motor has a safety feature on it that will not allow the motor to run above a certain RPM if it starts to slightly overheat? Here is why I am asking...

I notice that my motor isn't peeing water very well when my motor is at trolling speed or when my motor idles down as slow as it goes. But when I give it throttle it pees water better. I am only having issues after I let it idle for a minute or so or if I troll for any length of time. Which I am starting to wonder if it slightly overheats and puts it in some kind of safety mode


If I rev it up in neutral after I'm having this problem it increases the amount of water circulating through the motor(cools it) then all is fine and it runs like a top.


Could it be something as simple as an impeller that needs to be replaced or is this a stretch?

I'm curious why it's not peeing very well at low rpm.
While you had the leg off, I would have put on a whole new impeller kit.
As you can see in my video, it's pumping water very well.
Hope you get this figured out. Keep us posted.

https://www.youtube.com/watch?v=STC7bgueu10

 

[chiefcatchemall]

It pumps water much better now after I replaced the impeller. However after I reinstalled the lower unit all my shift linkage is goofy. My forward is actually my neutral and my neutral is actually my forward. It's a side so sole with a steering wheel and a shift lever up front. I wonder if it somehow got kicked into forward up by the steering wheel when I went to reinstall the lower unit.

 

[Bosunsmate]

maybe you put your cables on wrong, the throttle one onto the gear one