95 sport jet 120 fuel issue

[weiss19]

I have a 95 sport jet 120. The thing dumps fuel out of the front of both carbs within 5 seconds of me cranking it over. I've cleaned the carbs 3 times put a rebuild kit in one with no luck. I took out the carb pumped fuel to them with a primer ball and the seats held. I disconnected the auto enrichner same problem. Any body have any ideas what this could be that's causing this??

 

[MickLovin]

Others may have a better opinion of this issue, but you may have reed problems, but more than likely a float adjustment maybe your problem. "I took out the carb pumped fuel to them with a primer ball and the seats held."
I don't quite understand what you are saying in the above quote, do you mean you were testing your needle and seats? If so check your float levels.

 

[MickLovin]

I found it easier to have a spare pair of carbs and other parts for these aging motors.

 

[jerryjerry05]

Usually the floats would cause this.
You still have the old parts? Put them back in.
Most time the "new" stuff isn't any good and the carb could just need a good cleaning.
Pull the carbs and check the reeds.

 

[weiss19]

the floats were not replaced just the needle and you cant replace the seats on these carbs I have a manual and the floats were within spec. and I only put the rebuild kit in one carb the top is still original just cleaned. (both are pouring fuel) yes I took out the carbs and hooked up the fuel supply with a primer ball and pumped it till it was rock hard and the seats held perfectly. reeds or fuel pump possibility?? stuck a camera in the intake and reeds didn't look to bad but obviosly couldn't measure them

 

[pnwboat]

When you say you disconnected the auto enrichener, what exactly did you do?

 

[weiss19]

Un wired it and disconnected the lines to and from it and plugged them off to see if some how the fuel was being over delivered from that and running out the front of the carbs. After I tested it and resolved nothing by doing this I rehooked everything back up the way it was

 

[glenn property of pam]

history: did this happen before you done any work to the carbs, is the motor new to you, etc
I suggest looking at a explosion diagram and checking that all jets, plugs are installed and in the correct place.

 

[pnwboat]

If you have the old needle valves, compare them with the replacements. Make sure that they're the same length. From what you're saying when you disconnected the enrichener valve, it's completely out of the picture. I've had a few re-build kits where for what ever reason, I had to re-adjust the float level to get the needle valve to work properly.

You said that you "took out the carb pumped fuel to them with a primer ball and the seats held." What exactly do you mean by took out the carb? The carbs should be mounted in place on the motor in it's normal running position to test the needle valve seal with the primer bulb. You cannot test them correctly by holding the carb in your hand and squeezing the primer bulb.

The fuel pump does exactly the same thing as the primer bulb. If it doesn't leak with the primer bulb, then it should not leak when the fuel pump is supplying fuel. If fuel is coming out of the carb, then the test with the primer bulb was not done correctly, or the fuel is getting blown back out of the motor due to broken reed valves.

 

[Frank Acampora]

First off, the inlet seats ARE replaceable--you just need to want to do it badly enough. They are pressed-in . You take an appropriate sized self threading screw and screw it into the seat then use the head to pull the seat out. New seats are pressed-in with a small amount of sealer. HOWEVER: Since the seats are plated and metal, and since the needles are rubber-tipped, the seats very rarely wear to the point of needing replacement. Usually the rubber tip of the needle fails.

Now: Float level should be set so the float is level with the carb casting with the carb inverted. With the carb inverted, the weight of the float should seal the inlet against mouth pressure--that is, you should not be able to blow into the inlet. With the carb in its correct upright position you should be able to blow through the inlet with a little resistance--after all, the opening is only between 1/32 to 1/16 diameter.

Also adjust the float drop. The bottom of the float should be just above the brass high speed jet. For adjustment, there is a tang on the back which bears against the casting, limiting float drop. IF the float drops too far, it can hang up on the high speed jet, not rising and allowing the pump to overfill the carbs.

 

[Nordin]

YES as Frank writing. Check the carbs floatlevel/adjustment.
As this is a quite "new" engine I suppose that the float is made of plastic and not of cork.
BUT check the floats so they not are full of fuel. I have hade an OB (OMC) that the float (plastic) was leaking and filled with fuel.
It did not rise and closed the inlet fuelvalve.

 

[weiss19]

Alright thanks guys I'll let you know what happens