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Discussion Starter #1
I have a 96 monster 900. I changed some fuel lines and now i can't get the gas to flow to the carbs. I checked the vacuum lines that come off the intake manifolds and they have pressure. so far i replaced the fuel filter and spark plugs and swapped in a new battery. even sucked on the line that goes to the carbs still no gas. before i get a rebuild kit for the pump is there anything else i can try. Now just so i have this right the top vacuum line goes to the carb. and the bottom line is the fuel supply. Please let me know if this is correct. the pump does not have arrows.
 

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Did it run before you changed the lines?
 

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Discussion Starter #3
When i pulled it out for the season she ran but started stalling when ever i stopped. So i pulled the carbs and had them cleaned that didnt help. I removed the pump and checked the diaprams they did not have any cracks or holes that i could see. So i put back together and started changing lines filter batttery fresh gas everything i could think of. Last summer i changed the coil pick ups and have changed the pressure plate but that shouldn't matter. I believe i'm missing somthin simple.
 

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What was the last thing you did before it stopped running completely? During all of these things you tried, did you check the fuel shut off valve's operation? Just guessing right now. Your chain of events is too jumbled to give an educated guess.
 

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Carbs

I have seen some of this before. What I did is :
1. Run the gas line directly to the carbs, no vacuum pump, no petcock. See if this runs okay.
You don't want to leave it like this, the idea of the two vacuums is to keep gas from running into cylinder and flooding crankcase when sitting for long periods of time if float bowls don't do their job.
It dosen't need these to work while running. If it doesn't run right, the carbs are a problem.


2. Then try reconnecting each vacuum , one at a time, and running to see if either causes the problem. I had to do all of this once, simply because I ran the tank dry and it sucked air into everywhere, when I reconnected everything again, all was okay.
I have some of these spares if you find them faulty.

I have a 96 monster 900. I changed some fuel lines and now i can't get the gas to flow to the carbs. I checked the vacuum lines that come off the intake manifolds and they have pressure. so far i replaced the fuel filter and spark plugs and swapped in a new battery. even sucked on the line that goes to the carbs still no gas. before i get a rebuild kit for the pump is there anything else i can try. Now just so i have this right the top vacuum line goes to the carb. and the bottom line is the fuel supply. Please let me know if this is correct. the pump does not have arrows.
 

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Discussion Starter #6
Thanks. The shut off valve is the next thing i'll check. the last time i rode the bike i went about two hundred yards and stalled at a stop sign. i tried to restart and the motor turned over but did not fire. In a panic i gave it some gas and if fired up. i turned around and came home. After that i checked all my connections wires, hoses and could not see anything wrong. i tried to start it back up and it's been dead ever since. After this i tried a bunch of things.
I know what the problem is. Its not getting gas. Maybe my visual inspection of the fuel pump diagram was off. I didnt see any holes or rips but a pin hole would be hard to see.
 

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Discussion Starter #7
Macduck

Thanks for the tip. I'll try tomorrow after work.
 

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Discussion Starter #8
I hooked the gas tank up direct bypassing the pet cock and fuel pump. She fired right up.after hooking up the fuel lines I can't get the fuel to run thru the petcock now. is there a trick? i can blow air thru the fuel inlet but not the fuel outlet. What should i do now?
 

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Fuel will flow through the petcock only when the engine is running (and hooked up properly) or if you pull a vacuum on it with a MityVac or similar device.
 

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Discussion Starter #10
what can i do if i don't have a mighty vac. Should i get the bike running and then hook up the fuel lines while fuel is still in the float bowl.
 

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Discussion Starter #12
Thanks for all your help. I used the mighty vac and she's running strong. A few more tweeks and i'll be ripping it up on the street.
 

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What did you find exactly?
 

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Discussion Starter #14
after priming the fuel lines, petcock and fuel pump she runs. I guess the flow of fuel was my problem. Thanks again. I hope some day i can help someone as much as you guys helped me.
 

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Glad you got it sorted. Now, go ride!
 
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