Pulled main fuel line from carburetors on my motorcycle,noticed fuel level is to the brim. Is this normal?

Question

Bike: '87 Yamaha Radian.

Engine: 600 4 cyl.

new plugs

tested wires

History:

Tank is slightly dirty inside, don't have the money to fix it yet. In-line fuel filter installed for now. There has been an in-line fuel filter on it since I bought it. I have had this bike running fairly well.

Bike was dying while running it hard. Noticed that the fuel filter was almost completely dry when this happens. When this happens I would just pull over and let it sit for a moment, choke it to start it, wait for it to stop running badly, and then continue on my way (usually straight home).

Solved issue with dying/cutting out at high speed:

Took the main fuel line off of the carburetors main inlet. Could visibly see metal chunks and shavings in the inlet (inlet is about 1 inch long). I pulled these pieces out and tried to get anymore with a magnetized paper clip. I'm pretty sure these carburetors will need a rebuild at this point.

Bike ran well for a couple months at this point.

Bike sat for a couple weeks (bought a new Harley Nightster).

Tried to start, bike will not run off of choke, revs go up and down on their own. Bike does not sound right, it sounds deeper and like it is possibly missing (not sure how to describe it). If I take it very far off of choke, the revs go down till the bike dies.

I took the main fuel line off of the carbs again. I was thinking it could be the same issue...

MAIN QUESTION:

When I took the fuel line off of the main inlet I noticed that the fuel level sits flush at the top of the inch long inlet. Is it normal for the fuel level of the carburetors' inlet to be flush with the top of the inlet? (It appears the fuel can not flow through the carbs while just sitting there with nothing connected... don't know if that's normal or not)

Answer 1

is your drain inlet clogged?

Answer 2

Drain your tank, Remove petcock (off and on switch on the bottom of tank). Allot of times there are screens on top of the petcock. clean it with a brush lightly. get some mineral spirits or parts cleaner. pour into tank and slosh it around a bit. drain it and repeat until you don't see any debris drain out. install the  petcock again and make sure a good stream is coming out when you turn it to on and reserve. when you clean your carbs take an air compressor and blow out the jets. be careful with all the brass pieces  within the carb. brass is easily bent or broken.never over tighten. if it has a diaphragm connected to the slide be careful with that also. a pin hole or any damage to that will make your bike not run so good. Blow all the fuel lines out and put it back together. buying a manual for reference may be a good idea.

Answer 3

your main problem is all those brolen bits of metal in the carbuerator. We all know thet this should not be there. Now as far as the fuel ank is concerned,any little dirt trying to get thru will be stoppped by the filter ( changing the filter was a very good move)

As for the metal in the carbuerator. The only thing i can think of is that at sometime in the past the inlet threads were re=reamed and died and a lousey job was made of it.

The carbuerator may have some of this metal in the jets,,,,thus the reason you have to keep it choked. Your not getting full fuel flow thru them and the choke is actually adjusting the air flow to agree with the fuel flow.

Your talking about fuel levels in the inlet?? That part of the post i dont understand. Are you talking about the float bowl?? With the jets stopped up anything ispossible.

Answer 4

Answer to your main question:  Yes, it is normal for fuel to be in your fuel line.  When the carburetor(s) are full of fuel, a float rises which closes a needle valve and stops the flow of fuel inside the carburetor.  There would still be fuel in the fuel line at this point.

You say there is rust inside the fuel tank.  Check your vent inside your fuel cap.  This is often overlooked.  If the fuel vent is not working correctly, a vacuum can build up inside the fuel tank to the point where it stops the fuel flow to the carburetor(s).  You can test this.  When the engine stops, try removing the fuel cap and restart the engine.  If it starts and runs correctly, you found your problem.

WARNING:  DO NOT RIDE YOUR BIKE WITHOUT A FUEL CAP FOR OBVIOUS REASONS. FUEL WILL SLOSH FROM THE TANK AND CAN CATCH FIRE.

In the furtue, store your bike with a full fuel tank.  With a metal fuel tank, condensation can form inside the tank during storage and cause rust.  Storing with a full fuel tank stops the condensation and assosiated rust.  Add some fuel satbilizer to the fuel tank so the fuel doesn't go bad during storage. After you add the fuel stabilizer, run your engine for a few minutes so it can get inside the carburetor(s) so they are protected also.

I use a product called Sta-Bil in my fuel tank during storage.  This can be found at any automotive parts store.  It is inexpensive to use.  It will keep your fuel fresh for over a year, 2 years if you double the mixture.