Another Issue

[deezelteck]

Hello,
I have done a lot of work on my 59 johnson 35hp, and I finally goy her out on the water a few times and it ran well for about 300 yards and then it acts like it is either flooding or running out of fuel. I can bring it back down to an idle (it will not die), then full throttle, and it will run great for about 300 yards again. I have adjusted and readjusted the carb several times. Any help is appreciated.

 

[HighTrim]

Re: Another Issue

Sounds like a fuel delivery issue. Will pumping the primer bulb pick it back up? Choking it? Spraying pre mixed fuel into the carb throats?

 

[tashasdaddy]

Re: Another Issue

are you running a single line tank, or double line pressure tank?
did you use these directions?
(Carburetor Adjustments - Two Adjustable N/Vs)
(J. Reeves)

Initial settings are: Bottom high speed = seat gently, then open 1 turn out. Top slow speed = seat gently, then open 1-1/2 turns.

Setting the high and low needle valves properly:

NOTE: For engines that DO NOT have a shift selection, obviously there is no NEUTRAL position. Simply lower the rpms to the lowest setting to obtain the low speed needle va /lve adjustment.

(High Speed) Start engine (it will run pretty rough), shift into forward gear, take up to full throttle. In segments of 1/8 turn, wating for the engine to respond between turns, start turning in the bottom high speed needle valve. You'll reach a point whereas the engine will either start to die out or spit back (sounds like a mild backfire). At that point, back out the needle valve 1/4 turn. Within that 1/4 turn, you'll find the smoothest setting.

(Low Speed) Slow the engine down to where it just stays running. Shift into neutral. Again in segments of 1/8 turns, start to turn the top needle valve in. Wait a few seconds for the engine to respond. As you turn the valve in, the rpms will increase. Lower the rpms again to where the engine will just stay running. Eventually you'll hit the point where the engine wants to die out or it will spit back. Again, at that point, back out the valve 1/4 turn. Within that 1/4 turn, you'll find the smoothest slow speed setting.

When you have finished the above adjustments, you will have no reason to move them again unless the carburetor fouls/gums up from sitting, in which case you would be required to remove, clean, and rebuild the carburetor anyway

 

[deezelteck]

Re: Another Issue

Thanks for the quick answers, I'll agree that it sounds like a fuel delivery problem. I also have adjusted the carb just as tashasdaddy specified (several times) I even printed that off and stuck it in the manual. Today I took the compression line off the back of the fuel pump, turned the engine over. There is a push pull action there and it is steady. Then I removed the fuel line from the carb and turned it over and I got fuel but how much do I suppose to get? I can hold my finger over the hose and it builds pressure, but it isn't pressure we need at full throttle it is flow right? Thanks for all the help with this.

 

[tashasdaddy]

Re: Another Issue

well when you are running a 4500rpms, you get a lot of those little pulses, building up flow. is the vent open on the fuel tank?

 

[deezelteck]

Re: Another Issue

The fuel tank vent is open, when I tested for the pulses it was in a barrel and not running. I was turning it over with the starter. Is it possible that the fuel pump is weak? The more I think about it it seems like it empties the fuel bowl and I can bring it back down to an idle so it can refill the bowl again and then it will take off again.

 

[steelespike]

Re: Another Issue

Gas should come out in strong pulses.
Your discription seems to indicate it uses up the gas at speed and when you slow it catches up.be sure all connectors are tight.Sometimes thay may suck air and not leak gas.

 

[deezelteck]

Re: Another Issue

Okay, I think I am going to replace the last two fuel lines that I haven't replaced, even though they look pretty new. Also I think I am going to put a kit into the fuel pump and install all new clamps. Thanks for all the help.

 

[deezelteck]

Re: Another Issue

Hello All,
I just wanted to finish this thread off, this weekend I replaced all the fuel lines and took apart the fuel pump. Inside the pump a screw had backed itself out and was keeping the diaphram from moving, after rebuilding the pump we took her to the lake. It ran better than it ever has, she still runs pretty rich but I think that is just her nature. Thanks for all the help.