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Discussion Starter · #1 ·
I installed a in line fuel filter a few months back as well as cleaning out the tank and sealing the inside to stop rust. Since then I have had to fill up my tank every 50-70 miles as it begins to act like it is out of gas. But just this week it has been doing that every time I take it out to ride it. I put a clear line from my petcock to the carbs (via a fuel filter) so i can see if fuel is getting to to the filter and into the tank. The filter never seems to fill up with gas and I wonder what the problem could be. I thought it might be the vacuum tube into the petcock so I re-tubed everything. I wonder if my petcock is not allowing enough gas into the line or if the vacuum is not working right or if the petcock is clogged or if I put the vacuum tube into the wrong slot. Any and all ideas and advice is very welcome. Thanks.







P.S. Love the new site look!!! Whoever the webmaster is, props man!
 

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If I bypass the petcock (as described in the picture) would that flood the engine or get too much gas into the system?


No because of a few other things. The petcock has an on off. Always turn it off when you aren't using it. Then when the gas goes in the carbs the floats raise pressing the fuel pins into the slots cutting off fuel flow to each carb.



As long as all of that is working you are fine.
 

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Goob, ya didn't say what type of filter or it's orientation, but here is how I set mine up. My filter is never full, only enough to meet the need of the carbs. So I don't know if this helps or not, but thought I'd toss it out. *edit to add, the petcock is in RESERVE position in that pic*

Joel in the Couve



 

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Oh, and one more thing, with that arrangement, I just need to spin the filter in a few months to utilize the top half of the element for the next phase.
 

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Discussion Starter · #9 ·
I can get the machine to start (Gas is drawn through the in line Fuel filter (much like the above picture) and it starts us just fine. But after it runs for a long while (like my commute to school) it will kill. If i give it a short amount of time (no more than 2 minutes) It will start up again and run again. I wonder if the fuel isn't feeding into the carbs fast enough or consistently enough to keep the bike running for long periods of time or at high RPM's. When I engage the clutch to stop and the bike isn't constantly revving it will sputter and kill as (as if not enough gas). The pilot screws on the carbs should be fine (it was working well earlier in the season without tweaking the carbs.
 

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you have the fuel filter fitted the correct orientation,yes_



if yes,than id bypass the petcock,then pull the feed off the carb and confirm a good flow
 

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My Guess is either the fuel tank breather is clogged, ( will it flow with the gas cap removed?) or your bike is an '82. IF it's a 1982+, it has a screen inside the petcock ( above the bowl on the bottom of the petcock, not in the tank itself)
 

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Discussion Starter · #13 ·
you have the fuel filter fitted the correct orientation,yes_



if yes,than id bypass the petcock,then pull the feed off the carb and confirm a good flow


So if I bypass the petcock then gas will flow freely from the tank. Right now if I take the gas tank off the bike and disconnect all the hoses even if the petcock is set to "on" or "reserve" gas does not flow out of the tank. It sure makes taking the tank off easy but would that imply that my gas cap is clogged and not allowing flow and that is why it works for a time till the vacuum in the tank is more than that of the petcock? I feel foolish asking this, but have I been barking up the wrong tree?



How would I go about clearing the gas cap if that may be the issue? I am at school but will check the flow with the gas cap off when I get home.



And yes the flow through the filter is going in the correct direction.
 

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So if I bypass the petcock then gas will flow freely from the tank. Right now if I take the gas tank off the bike and disconnect all the hoses even if the petcock is set to "on" or "reserve" gas does not flow out of the tank. It sure makes taking the tank off easy but would that imply that my gas cap is clogged and not allowing flow and that is why it works for a time till the vacuum in the tank is more than that of the petcock? I feel foolish asking this, but have I been barking up the wrong tree?



How would I go about clearing the gas cap if that may be the issue? I am at school but will check the flow with the gas cap off when I get home.



And yes the flow through the filter is going in the correct direction.
goob,if you follow this threadhttp://globalcxglvtwins.hostingdelivered.com/viewtopic.php?f=19&t=290 and bypass the vacumn need for fuel flow.your petcock will be simply an on off switch.then you can confirm a good constant flow from your tank.

the job is easily reversed if you so wish
 

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Someone beat me to it....



"make sure the gas cap has a hole in it" Sucking fuel out of the tank, must allow air in the top, or the tank has vacuum inside, and will stop flow.



Also, aftermarket filters (in-line) can slow the flow too much. As there is also a filter on the petcock.
 

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Discussion Starter · #17 ·
Alright. I finally figured out the problem. The petcock is not flowing properly to the tank I bypassed it and no fuel came out of the petcock assemble. This leads me to believe that the petcock is stopping the flow. I also drained the tank and the flow was constant with the gas cap on as well as off. I took the petcock off and took it apart. I have no idea what the assemble is supposed to look like, I can't just reverse engineer it because it was wrong in the first place.



I have 4 screws 2 rubber washers a spring and 2 sleeves one The sleeves and screws I know where they go but the assembly of the washers and spring is What I don't know. Any one have a diagram or know how it should go back together?
 

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Does the fuel petcock have a vaccuum pipe coming from it, like the Euro model?? My CX's have all had a one piece fuel tap, that cant be taken apart.
 

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These fuel taps require vaccuum from the inlet manifold to overcome a spring and a diaphragm that is sealing the flow of petrol. Most guys just reverse the diaphragm so it doesn't seal. Make sure you turn off the petcock when you stop, though.
 
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