Question about 1981 Suzuki GS 750 L
When i go to start my bike ineed to prime it first when the motors cold. Ive shot some carberator cleaner in it while the filters were off but still have the same problem. Maybe i just need to get some new K and N's
Runs like a dream after shes primed. But still I shouldnt have to do that on my 81,suzuki gs750
On most Japanese bikes, the PRI position allows fuel to flow from the tank to the carbs even if the engine is not running. In the ON position, the fuel gate valve would only allow fuel to flow if there is vacuum which of course would mean that the engine is running. There is normally a vacuum hose from the intake manifold of cylinder 1 that leads back to the fuel valve that triggers the internal diaphragm to open the fuel line.
If we are to assume that for some reason the PRI position is blocked, then switching the "fuel tap" to this position would not allow fuel to go down the carbs. Thereafter, the engine used what fuel was left inside the carbs (100 meters) and the engine died. Switching the "fuel tap" back to ON again would not allow fuel to flow down from the tank to the carbs since there is no vacuum and very little vacuum when starting the bike; and the bike would not start, no fuel inside the carbs.
Correct action of course would mean overhauling the "fuel tap" and initially setting it to PRI and then to ON soon as the engine is running on its own. Temporary remedy/workaround would be to manually feed fuel to all the carbs with the use of an external container with rubber hose/fitting. Alternately, you can try spraying starter fluid or car injector cleaner. This should be done with the air cleaner off. A word of caution, in some older bikes I have worked on, this condition would result to an overflow of the carbs soon as the engine starts indicating that the float(s) inside the carbs are sticking.
Hope this be of initial help/idea. Pls post back how things turned up or should you need additional information. Good luck and kind regards. Thank you for using FixYa.
Posted on Nov 11, 2008
Hi and welcome to FixYa,
Almost always, your described problem would be the float needle not closing the inlet seat. This could be caused by a dirt, sand, contaminant, worn needle ends, grooves on the seat. Unfortunately, the only fix would be to pull down the carbs again and redo. Considerations are:
Good luck and thank you for using FixYa.
Posted on Apr 28, 2009
You cannot bleed the fuel injection system.Test the pump alone (not on the bike) for sufficient fuel supply.Also check the fuel pump relay.
If all that is ok next time you try to crank the engine (only with kill switch on, the fuel pump primes up) with lifted tank and opened air box, spray a bit of carb cleaner spray towards the throttle bodies.It will help.
Posted on Jun 09, 2009
and your question is ... what?????
Normally, I would expect to see 'on' - 'off' and 'reserve' position. NEVER RUN ON RESERVE. Save that for when you run out of gas.
I don't know what prime really means in this case .,.. were I you, I'd run on on only.
Posted on Oct 30, 2009
The float is stuck open in the leaking carb. Remove the float bowl and clean the carb after removing the pin holding the float in place. While the float is out, shake it to see if gas has gotten inside it. If so, you will need a new float or will need to drain the float then re-solder it to seal it up again. To drain the float chances are you will need to drill a vent hole in it to allow the gas to drain. Just solder the vent closed when done.
Posted on Jul 14, 2010
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