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Fuel leak on new bike, need advice

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Old 01-27-2018, 03:25 PM
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Default Fuel leak on new bike, need advice

Hello,
I just picked up an '88 CBR600F with a fuel leak, the only evidence I have o this right now is that there is paint from the gear box has come off because of this.

I've spoken with the seller, and it was assumed that a gasket in the carbs may have dried up. I've done some reading and was thinking that the leak is, yeah, a dried gasket, or something else in the fuel line.

I've taken the tank off, and in doing so have noticed that a little hose that goes to a small port was disconnected--right above the gearbox, where the leak is evident. I don't know what these "extra" tube connections are for on the bottom of the tank, and they do not appear in the repair manual that I've got. The manual only shows the main fuel line coming off of the line switch, petcock. The tube that was disconnected is thin and runs straight down, I haven't looked into this further. I'm waiting until I get better lighting to work on this. There are 2 extra hose nipples on the bottom of the tank, what are these? Emissions related?
 
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Old 01-27-2018, 04:57 PM
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the larger is for the overfill under the fuel cap, the other is to equalize pressure inside the tank. one of the internal tubes in the tank may have a crack or pinhole thats causing the leak.
 
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Old 01-27-2018, 04:59 PM
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I've so far put everything together and have the tank lines hooked up securely and I've put 1 gallon into the tank, but the bike won't start/fire. Is there a minimum amount of fuel required in the tank to run? The fuel pump is clicking(?), the starter works, but it slows after a moment of trying to start. I've got the battery on a tender at the moment. I'm tempted to go down to the store and pickup some starter fluid. I'm guessing since the bike hasn't been run in a few months, the carbs may be gummed up and I should do the carb cleaning that I intended to do anyways.

So far, no leak. So, there's that I guess.

I appreciate any help in this matter,

Thanks
 
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Old 02-10-2018, 10:59 AM
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I've got a carb rebuild kit in the mail and am in the middle of taking the carbs off the bike.

I feel like I'm going to break the bike taking these things off, is there a trick to taking the carbs off?
 
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Old 02-10-2018, 11:09 AM
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patience and perseverance.
try warming the boots with a hair dryer. Theat will make them more pliable. Keep rocking them back and forth.
 
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Old 02-10-2018, 11:35 AM
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Hrm, no luck on the hair dryer.

Would using wd40 be a supremely bad idea?
 
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Old 02-10-2018, 12:46 PM
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i doubt you will get much help with WD40 but you can try. The boots have sort of welded themselves to the intake after all the years. Breaking that bond is what you are going for.
 
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Old 02-10-2018, 03:03 PM
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ok, so I've gotten as far as breaking the bond, i found a hair dryer(helped a LOT), and have removed the choke and throttle cables, but now I'm faced with a ridiculous web of vacuum tubes/drain tubes that are not in my service manual.

Does anybody have a good image or diagram for what all these tubes are? '88 cbr600f
 
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Old 02-10-2018, 03:26 PM
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Originally Posted by taintedaether
ok, so I've gotten as far as breaking the bond, i found a hair dryer(helped a LOT), and have removed the choke and throttle cables, but now I'm faced with a ridiculous web of vacuum tubes/drain tubes that are not in my service manual.

Does anybody have a good image or diagram for what all these tubes are? '88 cbr600f
Alright. I got it out. There were two tube disconnects I needed to perform, a small tube going to the header(?) and another where the drain tube goes down right infront of the rear wheel.

Would it be worth while posting pictures of the carb to get an idea of what is going on? It looks like somebody did some liquid gasket, and the underside of all the float chambers is stained in gasoline. My guess so far is that it has been sitting, and there is a gasket leak. Jets need clean/replacement(to get fuel into the cyclinders/start the damn thing lol) and the gaskets need to be replaced(stop the leaking).
 
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Old 02-10-2018, 03:27 PM
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Pictures are always a good thing. Liquid gasket on the other hand isn't.
 


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