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Hi all! My name is Phil and I recently bought a 1983 suzuki GS750. Awesome bike. Ran great for the first hundred miles or so then just bogged down and had a low idle. I checked the spark plugs, spaced them correctly, checked out the carb and when I was doing so I saw no fuel in the fuel line. I disconnected the fuel line from the fuel filter put some gas in the tank and got no fuel coming from the line. Could this be a clogged fuel line or dirty tank? What should my next step be?
 

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Yes but it also could be that the fuel valve (petcock) is in the wrong position OR that the vacuum fuel cutoff feature of the petcock has failed.
If it has a PRIme setting, fuel should always flow in that position......unless there is an obstruction in the line or tank.
 

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Yes but it also could be that the fuel valve (petcock) is in the wrong position OR that the vacuum fuel cutoff feature of the petcock has failed.
If it has a PRIme setting, fuel should always flow in that position......unless there is an obstruction in the line or tank.
Okay okay cool. What would be the next step to take if it is a failing fuel valve?
 

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For a short time you can use it in the PRIme position.
But if you park inside a garage or other enclosed space it really should be turned OFF each night (the position that is supposed to be automatic ON is now OFF).

First find the vacuum hose from petcock to carb and be sure it isn't loose or leaking.
The pull that hose loose at the petcock end and check for vacuum with the engine running.
If the vacuum is good but the fuel still won't flow in the ON position, then you need to replace or rebuild the petcock.
A shop probably could do that for you for about $100 or less.
 

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For a short time you can use it in the PRIme position.
But if you park inside a garage or other enclosed space it really should be turned OFF each night (the position that is supposed to be automatic ON is now OFF).

First find the vacuum hose from petcock to carb and be sure it isn't loose or leaking.
The pull that hose loose at the petcock end and check for vacuum with the engine running.
If the vacuum is good but the fuel still won't flow in the ON position, then you need to replace or rebuild the petcock.
A shop probably could do that for you for about $100 or less.

Theres fuel in the line now but unfortunately it hasn't turned over for more then 30 secs. With a low idle.
 

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Could also be the fuel valve filter...inside the tank...might also want to check the tank vent is working OK.
 

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but unfortunately it hasn't turned over for more then 30 secs. With a low idle.
What exactly do you mean by that ? That it won't RUN for more than 30 seconds ?
Do you have the choke fully ON ? Maybe the idle speed needs to be set a bit higher.

This probably means that the idle jets are gummed up and/or there is a vacuum leak in the hose to the petcock or inside the petcock itself.
 
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