No vacuum #1 carb


Information and questions on GL1100 Goldwings (1980-1983)
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Orpheus75
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No vacuum #1 carb

Post by Orpheus75 »



Just rebuilt my carbs and got them back in. Connected the sync gauges and..... no vacuum whatsoever in #1 carb. I pulled the cap off/loose and inspected the spring and piston, seems okay.. but nothing when I run the bike.
I guess then it goes to possibly no fuel getting through the jets/carb? Should I open the needle up a bit? Or is this where I get to pull the carbs out (again) and check the whole rebuild on that one?
I did check the spark plug with a tester and the plug is firing, so it's not an ignition problem. Pretty much looks like an issue with the carb.


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Maz
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Re: No vacuum #1 carb

Post by Maz »

Orpheus75 wrote: Wed Jun 21, 2017 9:48 am Just rebuilt my carbs and got them back in. Connected the sync gauges and..... no vacuum whatsoever in #1 carb. I pulled the cap off/loose and inspected the spring and piston, seems okay.. but nothing when I run the bike.
I guess then it goes to possibly no fuel getting through the jets/carb? Should I open the needle up a bit? Or is this where I get to pull the carbs out (again) and check the whole rebuild on that one?
I did check the spark plug with a tester and the plug is firing, so it's not an ignition problem. Pretty much looks like an issue with the carb.
Vacuum is caused by the engine drawing in air
through the carbs as the piston moves down the cylinder on the inlet stroke. If the throttle butterfly is wide open, or there is a massive air leak around the inlet manifold, you won't get vacuum. Likewise if the exhaust valve is stuck open. Check that the throttle butterfly on #1 is opening /closing correctly. Also check your sync gauges by swapping the connections.
Maz
Ironically, Common Sense is the LEAST common of all senses!
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Orpheus75
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Re: No vacuum #1 carb

Post by Orpheus75 »

Already swapped gauges... all good there. (Would have rather it been my gauge )
Butterflys looked good before I installed, but will double check that just in case.
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virgilmobile
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Re: No vacuum #1 carb

Post by virgilmobile »

Does that cylinder have compression and could your "tap" that hooks to the intake be plugged?
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Orpheus75
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Re: No vacuum #1 carb

Post by Orpheus75 »

I'll check the tap and see. But I suspect it's clear. I'll make sure my tubing isn't damaged too. But since the gauges read both ways (pressure/vacuum) and NOTHING happens either way, and if the line is clear and good.. I suspect I have a major piston/engine issue. :(
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Orpheus75
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Re: No vacuum #1 carb

Post by Orpheus75 »

well, while the tubing was clear, the brass tube connector had a clog in it (phew). I blew it out and things are good and back to normal and all is well with the world again.
Thanks for all the advice! :)


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