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Discussion Starter #1
im getting real sick and tired of this bike...1 problem after another.
the plugs keep fouling out (probably due to dirty carbs)...yet the carbs were cleaned by an autoshop my brother works at (carb-guy cleaned them)..and 250miles later...im getting the same crap.
i can get the bike to start and idle w/ little resistance (still backfires and takes a few seconds to turn over), but it will only idle with the fuel off. if i turn the fuel to 'on'....the bike stalls out. if i turn it to reserve...it stalls out. and if i turn it off and try to start it, after a few seconds its fine. :confused: :confused: :confused: :confused:
 

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Discussion Starter #3
SqDancerLynn1 said:
The carb float valves are gummed up, dirty and need to be cleaned, Was the tank cleaned??
carbs were both cleaned 250miles ago. im taking them off to clean them again tho :sigh: and i was told to flush out all the fuel lines as well. the tank doesnt look dirty or gummed up (still has almost a full tank) as it hasnt even sat for more than a day since ive had it.
 

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Had the same thing happen with my DRZ400

If your fuel switch is "prime" not truly off. That's how my DRZ is set up:

On Res Prime

I had loosened my tank to tighten a loose throttle cable and pulled off one of the fuel vent lines. Without it, it would start on prime, I'd turn it to on, take off and she'd quit by the end of the street. Same on RES. Really frustrated me too, then I moved the tank again, thinking I got some dirt in it or something, DUH! saw the little vacuum line off, hooked it up, problem solved.

Hope this is all it is for you. Check your fuel selector, should be several lines running into it.
 

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Discussion Starter #5
the 2 lines going to it are where's they're suppose to be (different sizes. lol). it just started doing this yesterday after i swapped plugs twice in 5 min after them being fouled out. so i hope after i clean the carbs out it will stop flooding the cylinder (which is what i think is happening)
 

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I'll bet you have a vacuum operated petcock. one of those lines is where the fuel goes into the carbs, and the other is a vacuum line that probably hooks to between the carb and engine head. if there is no vacuum, no gas will flow from the petcock.

another possible reason is your petcock is gummed up. you can take it off the tank(empty the tank first) and open it up and clean it out.

replace the fuel line, it's cheap.
 

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I just saw what bike you have, the positions for your petcock are RES, ON, and PRIME. if its in the prime position, gas will flow freely. but in the on or res positions, the vacuum hose needs to be working properly to open a valve in the petcock. In the ON and RES positions, when you turn your bike off, there will be no more gas flowing to the carbs which is what you want. so leave the bike in the on position when the bike is turned off. then when you want to start your bike again, put it in the prime position to fill the bowl with gas and once the bike is started, switch it back to ON.
 

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Discussion Starter #8
LifeLiberty said:
I just saw what bike you have, the positions for your petcock are RES, ON, and PRIME. if its in the prime position, gas will flow freely. but in the on or res positions, the vacuum hose needs to be working properly to open a valve in the petcock. In the ON and RES positions, when you turn your bike off, there will be no more gas flowing to the carbs which is what you want. so leave the bike in the on position when the bike is turned off. then when you want to start your bike again, put it in the prime position to fill the bowl with gas and once the bike is started, switch it back to ON.
is it normal to have to do that? also, when the bike is running after its on prime/off, when i switch it to on after its been idling, it dies.

i have almost a full tank so it's gonna be a b*tch to empty it to clean everything. does the petcock come off independently from that tank? (im at school right now so ic ant go look). i plan on take the carbs off tonite to shoot the sh*t out of them with carb cleaner so ill try to do the petcock/fuel lines while im at it.
 

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Prime is not off. ON is actually the off position when the bike is also turned off.
prime means "prime the carbs"/ flow gas to carbs. you only want it to be in prime when starting the bike or if the bike is running. but if you run the bike in prime, you won't have any reserve tank. if the bike is off and you left the petcock in prime position, gas will continually flow to the carbs which will in return flood your cyclinders and get gas into the oil and possibly the airbox. the floats are supposed to stop this flow of gas, but in my experience, they can't be trusted. so you need to work the petcock like it is supposed to be used, that is what it is there for, to only supply gas to the carbs when you want it to, and to stop gas flow when you want it to.
 

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I think Epee had it right also. your vacuum hose probably came off the vacuum nipple that it is supposed to be on. Running the bike in the prime position won't hurt the bike any, but if the bike is turned off, move the petcock to ON or Res so that the flow of gas to the carbs is turned "off"
 

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Discussion Starter #13
well here's what i found out...
i cleaned the carbs and put them on the bike. started up after a little bit and was idling fine. then i noticed the petcock was on "off", so after the bike was idling for a few min, i turned it to "on". after a few seconds, i noticed fuel overflowing from the right carb and would stall the bike (flooding). so i turn the fuel off, start the bike and it starts fine. but as soon as i turn the fuel to "on" or "reserve" the carbs flood and stall the bike. but it idles fine w/ it "off".

i took the tank off and put an empty vac line to to vac nipple of the petcock. when the fuel is off and i suck through the vac line, only a little "spurt" of fuel comes out. so if i wanted to fill a cup, i would ahve to suck, pause, suck, pause, etc.
with the fuel "on", if i just do one suck, the fuel runs and runs and runs until i stop. same goes with the reserve. i dont think this is how a petcock is suppose to operate. cuz if it's always been like this...ive never had fuel flood out of the carbs before. :confused:
 

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BuRn__ said:
with the fuel "on", if i just do one suck, the fuel runs and runs and runs until i stop. same goes with the reserve. i dont think this is how a petcock is suppose to operate. :
That is how it's supposed to work. your floats are not set correctly.
 

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BuRn__ said:
then i noticed the petcock was on "off", QUOTE]

what is written on your petcock when you have it on "off"? what does the positon of the petcock say?

it just seems to me that you don't know how it is supposed to work and what everything on that vacuum petcock does. as long as you are getting gas flow from your petcock to the carbs when the bike is on, and you are able to stop the flow of gas to the carbs when the bike is off, then your petcock is working fine. it's job is to allow and stop the flow of gas, it's job is NOT to regulate the amount of gas flowing. sounds like the floats are not set correctly which is allowing too much gas into the carb bowls, which is then going to the overflow.

http://www.dansmc.com/carbs.htm

Floats control how much gas there is in the float bowl. The Tang of the float presses on the float needle (fuel inlet needle) letting gas into the float chamber when the level is low and shutting it off when it gets too high. If the Tang is metal, you can adjust the float level by bending it up or down. If it is plastic, it is not adjustable. Float levels are different for each bike and are found in the bikes shop manual. If you don't have the float setting and can't find it anywhere, set it so the fuel level is a bit below the top of the float bowl. Make sure no gas comes out of the Float Over Flow Tube/Hose. The Float Over Flow Tube is at the bottom of each carb. That should get you in the ballpark. Adjust the fuel level down from there as needed. There are many styles of floats. If you have copper floats, and the bike has been sitting out in the cold, with the temperature down below freezing, it's possible for water to get into the carb and freeze. This can crush the floats and make the carb overflow, when you turn on the gas in the spring. Too high of fuel level can cause the carbs to leak too.
 

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Discussion Starter #18
LifeLiberty said:
what is written on your petcock when you have it on "off"? what does the positon of the petcock say?
it says "res" "on" "off"...i dont have a "prime" option.

anyways, i broke down the carbs again today and pulled out the floats. the carbs that was overflowing seemed to have a lot omre travel than than the other side. so i pulled the thick pin that attaches to the plastic float and saw a piece of gunk in there. (could barely see it). so i got it out and now the float sits normal with the other side. i start the bike up with the fuel "on" and it idled fine for the most part for about 5 min (where it wouldnt even do 20seconds before). so thats looks to be what the problem was.

why didnt the cool-guy engineers that chose to use carbs...ever use a fuel filter? seems that carbs get clogged WAY WAY too easy.
 

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glad you found the problem. sounds like your petcock is gravity fed then if there is no prime. but that is wierd cause the diagrams at buykawasaki.com show that petcock as being vacuum operated.
 
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