Carb Problem, banshee related but off topic but desperate

[81-Delorean]

Hi all, first off I would like to apologize and hope you will forgive me but I do not have a banshee BUT i do have a '85 RZ350 bike which you may

or may not know is where the banshee motor came from. Anyway, I have a problem and I have tried posting to the RZ forums but they seem to be

about worthless so I am hoping you will give me a shot. I went to start my bike one day and when I kicked it over LUCKILY it didn't fire because I

had nothing but a straight hard stream of fuel come out of the exhaust pipes. I pulled the pipes off and sure enough they were full of fuel. I thought

my petcock may have failed so I rebuilt it and it works as it should, no fuel coming through when it's not running unless you turn it to PRI. OK, I

started it up without the pipes on (and after all the fuel was out of the engine of course) and i ran like a champ so I put the pipes back on and let

it sit over night. Went out the next day and sure enough there was fuel leaking under the bike again and not from the overflow tubes. I smelled

the pipes again and it smelled like gas so I pulled them and sure enough I dumped fuel out of them again. Next I pulled the fuel line off the carb

and nothing came out so I am assuming it is still working as it should. My problem is why is it still filling up with fuel through the carbs and straight

through to the engine? I pulled the carbs again today, checked the float needle and didn't see anything, checked the float height and it checked

out fine. I don't know what to do. Any Ideas anyone? Agai, I apologize for it not being banshee specific but it is related sort of. Thanks in advance

for any help.

 

Jason

[bansheeseat$$]

Not sure if this on track but try leaving the fuel cap loose on the tank and see if it still has the issue,Maybe the tank vent is pluged and when the pressure in the tank gets to high it is pushing fuel threw the fuel valve instead of venting it.Not sure if this helps ya but it is a free test anyways.

[Burt Reynolds]

Maybe your overflow channel on your carbs is clogged,and your floats are wrong at the same time,longshot but maybe.

 

I dont see how you could be getting raw gas in the exhaust and not overflowing the carbs,is there gas built up behind the carb too?like in the rear carb boot?

[Larry's Shee]

Brillant answer seat$$. Cap might let air in but not out. Heat from engine would radiate up to tank, expanding fuel. Fuel valve may hold fuel at atmospheric pressure, but not above. Was also going to mention that it might be leaking thru reserve part of valve but see you rebuilt fuel valve. Don't know where you live, but around here there is a small mud dauber wasp that LOVES small round holes for laying egg. If your bike has set for very long they might have attacked. Check ALL vent hoses on bike including battery. These little effers also like grounding outlet on wall plugs.

[Overboost]

sell it, buy a banshee

 

problem solved and more fun

 

seriously, I have never heard of fuel comming out the exhaust like that.

it wouldhave to fill the cylinders, then come out the pipes, you would lose over a gallon of gas there, and have some major problems.

I have had fuel injectors spray constang that filled a cylinder but never a carb of any sort.

 

this should be interesting.

[slopoke]

sell it, buy a banshee

 

problem solved and more fun

 

seriously, I have never heard of fuel comming out the exhaust like that.

it wouldhave to fill the cylinders, then come out the pipes, you would lose over a gallon of gas there, and have some major problems.

I have had fuel injectors spray constang that filled a cylinder but never a carb of any sort.

 

this should be interesting.

 

here goes my two cent worth. Fisrt the rz pipes go under the bike i think and the engine is on a tilt so if the condition is right the cylinders will fill up and the pipes and never come out the overflow. My banshee has done the same thing filling th pipes and never coming out the overflow. Here is what I found after pulling carbs so many times i could do it blindly setting floats and cleaning I founf that the rubber oring that goes on the brass seat in the carb was cut on both carbs. The petcock would leak ever so slightly over a long period it would just fill the motor up. If you look closely the side overflow tubes or vents are higher than the intake and exaust port and if the lower tube (hose coming out the bottom) is stopped up the fuel is going where ever it can. good luck and i guaretee you these guys on here will figure it out. They are great!!!