9.5 hp carb help needed

[Lion hunter]

1966 9.5 johnson. Starts and idles great. When I go to high speed fuel comes out of the high speed orifice and it starts to miss. I beleive that it is starving for air when the orifice get fuel in it and that it is a bad float, or stuck float needle. If I plug the hole with my finger it dies. Anybody have any other ideas before I tear this thing apart? Thanks in advance for any help.

 

[ezeke]

Re: 9.5 hp carb help needed

The high speed orifice or jet is located at the bottom of the float bowl and not visible except with the float bowl drain plug removed.

Of what part are you speaking?

 

[Rick.]

Re: 9.5 hp carb help needed

I'm not sure what it is your calling a high Speed orifice. The high speed jet is internal and not accessible unless you have the carb. apart. There is nothing I'm aware of that you can put your finger over. Can you show us a picture? Have a look here at the 1968 and use it for numbers if it is the same as yours. Rick.
http://shop2.evinrude.com/ext/index.aspx?s1=e015b42fd5e29a32664a94d259bf1f31

 

[Lion hunter]

Re: 9.5 hp carb help needed

Ok, it is not numbered in the diagram but it is the hole that is directly above #33 in the diagram. It is part of the top of the carb. If I blow air through it it comes out the hole right behind the float valve. Also, I have not got my manual yet so can anyone tell me what the float measurment should be.

 

[Lion hunter]

Re: 9.5 hp carb help needed

It is below #49 and behind the screw.

 

[Lion hunter]

Re: 9.5 hp carb help needed

Sorry to keep asking so many questions. What would the result be if I had the motor trimmed at to steep an angle and with just me in the boat it put the motor at to much of an angle? Just a crazy thought.

 

[ezeke]

Re: 9.5 hp carb help needed

The float is hinged from the aft end of the carburetor; tilting the motor out raises the float, closing the float valve more tightly.

The hole on the engine side of the carburetor (see thumbnail) should always be open, but no fuel should flow out in normal operation.

The cork float may be saturated causing it to keep the valve open and flooding the engine. They are sealed in shellac that is disolved by the alcohol in the fuel, so they need to replaced rather frequently. Some popular decarb has alcohol base, so it makes that problem worse. See: http://www.montanajacks.com/msds/seafoam-msds.pdf

Only way to get the new float is in the OEM carb kit 382048 or buy the float alone #379154.

 

[Lion hunter]

Re: 9.5 hp carb help needed

Ok I think that I may have found a similar situation here. http://forums.iboats.com/showthread.php?t=248005

I tried the float in a bowl of gas and it seemed to float well. I took the top off the carb and cleaned everything and blew out all the holes, and added some Sea Foam to the tank. Guess I'll see tommorow if it worked.

 

[Lion hunter]

Re: 9.5 hp carb help needed

It's not leaking from where you asked in the pic. Just Starboar of the low idle mixture screw spring is a screw for attaching the top of the carb to the bottom. Directly aft of that is a tube/hole, that is where the fuel is coming from.

 

[ezeke]

Re: 9.5 hp carb help needed

Be sure to have the clip between the float arm and the needle.

 

[Lion hunter]

Re: 9.5 hp carb help needed

My float needle does not have a mushroom head to attach a clip to. There is no clip there. Here is a pic of where it's leaking from. I kinda jumped the gun and passed over the part of your post about the Sea-Foam Hopefully once won't hurt it.

 

[ezeke]

Re: 9.5 hp carb help needed

Yes, that needs to be plugged with lead shot - use a large punch to drive it. You could close it with a small sheet metal screw and a sealer I guess.

 

[ezeke]

Re: 9.5 hp carb help needed

You have a real antique set-up; they haven't used that needle for over twenty years. If you use the one with the clip the float has control of the needle; it all comes in the kit.

 

[Lion hunter]

Re: 9.5 hp carb help needed

I don't understand having to plug that hole. If I put my finger over it the engine dies. Am I missing something here? Such as the high speed jet being plugged and having to pull aire from that hole.

 

[ezeke]

Re: 9.5 hp carb help needed

I have six of the 9.5 motors. The carburetor in the picture is old, but right out of the box, never used. All of them have that hole plugged and my motors run well.

 

[Lion hunter]

Re: 9.5 hp carb help needed

Ok I'll give it a try. My gut feeling is the high speed jet is plugged and is compensating by pulling air from the tube in the picture. I'll try a see, if not I'll get a kit and rebuild the carb. Any thoughts as to why it would die when I plug this hole would be helpful. Thanks again for all the advice. This site has helped me rebuild several motors.

 

[ezeke]

Re: 9.5 hp carb help needed

Probable that the lean/rich setting was adjusted to compensate for it being open.

 

[Lion hunter]

Re: 9.5 hp carb help needed

Went and got a carb kit. Rebuilt the carb and plugged the hole. Put it in the water and it wouldn't start. Fuel would come out of the hole below the choke valve as I cranked, and cranked, and cranked. Unplugged the hole and it started right up, but then the fuel came out the hole again at WOT. Everything was cleaned and clear before I put the carb back together. I tried moving the low speed screw in all the way and up to 4 turns out and there was no change. I lowered the float and all I did was run out of fuel. I am completly stumped. If that hole is supposed to be plugged why it will only run if it is open. And why does fuel come out of the hole.

 

[Lion hunter]

Re: 9.5 hp carb help needed

Ok the hole that fuel comes out of in the attached picture feeds into the top of the float bowl (The arrow in black not red). At WOT it is acting as a vent. If I plug that hole it creates a vacuum that does not allow fuel to flow. The only way fuel could come out of that hole is if there is pressure going into the float bowl somehow. So I either still have the float set wrong and the fuel pump is loading up the bowl or else I have no other idea.

 

[Lion hunter]

Re: 9.5 hp carb help needed

I have a theory and maybe a fix. I assumed that I was getting pressure into the float bowl somehow. When I pumped the primer bulb really hard I found a leak in the fuel line. Being that this line is drawing a vacuum I assume that it would be pulling air into the line under power. More power = more air. After time the air would have nowhere to go but out the vent and push fuel out with it. I have to test it tommorow. I may be just grabbing straws at this point.