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Main Area => General GS500 Discussion => Topic started by: Suzguy01 on July 25, 2015, 07:43:03 PM

Title: Broken Vacuum line from carb enough to keep bike from starting?
Post by: Suzguy01 on July 25, 2015, 07:43:03 PM
When I first got this bike it was running on one cylinder due stuck exhaust valve, where the hose connects to the carb had glue on it and Im not sure if it was connected when the bike started previously. The carbs were cleaned very recently prior to me getting the bike. I replaced the head, checked the timing and valve clearances, and all hose routing. The plugs spark, with the plugs out it feels like it has compression but I haven't measured it or anything. I put in a new battery, when trying to start all electronics work and engine cranks but doesn't turn over. I have noticed fuel leaking into the airbox from the carbs, I know this prob has something to do with float bowls being stuck. But could this broken line also cause the fuel leaking issue? Also would this line be enough to prevent the engine from starting? What else should I check for? Thanks!  (http://i59.tinypic.com/21jniuf.jpg)   (http://i60.tinypic.com/30u8sgn.jpg)
Title: Re: Broken Vacuum line from carb enough to keep bike from starting?
Post by: Watcher on July 25, 2015, 08:25:16 PM
Vacuum leaks will definitely cause issues.  The vacuum does open the fuel valve, but if you are saying the carbs overflow then it IS opening the petcock...

But the carbs sucking in so much air from the vacuum port means no vacuum to pick up fuel through the venturi.  Could be starving the engine.
Title: Re: Broken Vacuum line from carb enough to keep bike from starting?
Post by: Suzguy01 on July 25, 2015, 08:55:02 PM
Should add even tried starter fluid.. and nothing at all
Title: Re: Broken Vacuum line from carb enough to keep bike from starting?
Post by: Cosimo_Zaretti on July 26, 2015, 03:28:29 AM
Do you definitely have spark?
Title: Re: Broken Vacuum line from carb enough to keep bike from starting?
Post by: Suzguy01 on July 26, 2015, 07:37:20 AM
yes,  have taken out both plugs and checked
Title: Re: Broken Vacuum line from carb enough to keep bike from starting?
Post by: Janx101 on July 26, 2015, 11:05:19 AM
In those pictures. .. the top of photo little white plastic cap thing with the small white tube sticking out... pretty sure that should have a vac hose on it.... there's threads asking about how to fix the broken tube so can reconnect hose. .. so it must be necessary!  :thumb: